unsloth/studio/backend/core/inference/inference.py
Michael Han a00fe86c13
Studio: read model text as utf-8 so umlauts survive on Windows (#7467)
* Studio: read model text as utf-8 so umlauts survive on Windows

Chat rejects or mangles non-ASCII on Windows: "ä ö ü" in a prompt, a chat
template, or a model path comes back as mojibake, or the load dies with
UnicodeDecodeError.

open() and Path.read_text() fall back to locale.getencoding() when no encoding
is passed. On Windows that is the ANSI codepage (cp1252, cp932, cp1251, ... by
system locale), never UTF-8. Hugging Face writes these files as raw UTF-8, so
every read of one decodes with the wrong codec:

- tokenizer_config.json, which holds the chat template. Templates routinely
  carry -> arrows, smart quotes and CJK, so this is the common path into chat
- config.json and adapter_config.json
- modules.json, Ollama manifests, and the .py sources the remote-code scanner
  reads before a model is allowed to load

The llama-server and embedding-server stdout readers have the same problem via
subprocess(text = True); they now decode utf-8 with errors = "replace" so a
stray byte cannot kill a log reader.

Encoding arguments only, no logic changes.

tests/test_chat_text_encoding.py covers a config.json and a chat template
holding umlauts, arrows and CJK, plus the remote-code scanner reading a source
file with umlauts. Those pass anywhere the locale is already UTF-8, so a fourth
test re-runs the readers under -X warn_default_encoding and fails on any
platform if an encoding argument goes missing again.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Studio: name utf-8 explicitly on the remaining text I/O, with an AST guard (#7465)

* Studio: name utf-8 explicitly on the remaining text I/O

Follow-up to the model-text reads in #7467, covering the rest of the backend:
system probes (nvidia-smi, amd-smi, powershell, git, node), package installers,
/proc and /sys readers, and internal marker files (pid, install id, bootstrap
password, Colab credentials).

Same reason as #7467. open(), Path.read_text()/write_text() and
subprocess(text = True) fall back to locale.getencoding(), which on Windows is
the ANSI codepage rather than UTF-8. These paths are mostly ASCII today, so this
is hardening, not a live bug. Encoding arguments only, no logic changes.

Adds tests/test_text_io_encoding.py: an AST guard walking every backend source
and asserting text I/O names its encoding, so the class of bug cannot creep back
in one call at a time. 275 files.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Catch aliased subprocess and positional Path.open, migrate legacy JSONL

The guard only matched a receiver literally named subprocess, so worker.py's
`import subprocess as _sp` hid three text = True installs that decode pip
output with the ANSI codepage. It also skipped any .open() with more than one
positional argument, though Path.open takes buffering/encoding/errors/newline
positionally.

Resuming a scrape written by an older release is the other half: those JSONL
lines are in the locale codepage, so the UTF-8 preload raised, the dedup keys
were silently forgotten and duplicates were appended to a now mixed-encoding
file. Decode with the locale codepage as fallback and rewrite as UTF-8 before
the append handle opens, since Windows cannot replace a file it holds open.

* Stream the JSONL preload and keep a torn line from relabelling the shard

Reading the whole shard to migrate it was wrong twice over. These files reach
gigabytes on a large scrape, so the preload now streams line by line and the
rewrite streams through a temp file.

Worse, one interrupted append used to condemn the file: the whole-file UTF-8
decode failed, every byte was retried as cp1252, and the rewrite persisted
mojibake over records that were fine. A line now counts as legacy only if the
locale codepage both decodes it and yields valid JSON, which a torn UTF-8 line
does not. Damaged lines are skipped and copied through byte for byte.

When the rewrite cannot be written at all, the append handle opens with the
legacy encoding rather than mixing UTF-8 into the file.

install_wheel takes run = subprocess.run as a parameter, so the guard cannot
see it. Both wheel installs there now name their encoding.

* Decide the shard's encoding from the file, not one line at a time

Some byte strings parse both ways. cp1251 `Р°` is D0 B0, which is also valid
UTF-8 for `а`, so a UTF-8-first parse quietly showed the wrong text instead of
migrating it.

A line now yields both readings, and the file decides. Any line that parses
under the codepage but not as UTF-8 is unambiguous evidence, and ambiguous lines
then follow that verdict, which is enough for any real shard: ordinary Cyrillic
or Japanese prose is invalid UTF-8 several times per line. Keys for ambiguous
lines are re-derived from the legacy reading during the rewrite.

A shard is undecidable only if every line is ambiguous, and nothing can tell
those apart.

latin-1 is also tried after the locale codepage, so a scrape carried from
Windows to a UTF-8 machine still has a reading rather than none. Requiring valid
JSON, not just a decode, keeps that from claiming torn lines.

* Weigh the whole shard, and never lose a record on the fallback path

One structurally valid JSON line carrying a stray 0x96 parses as cp1252, so a
single-line verdict let it relabel a healthy shard and mojibake every good
record in it. Each line with non-ASCII bytes now votes: parsing only under the
codepage is evidence for legacy, parsing as UTF-8 is evidence against, since
codepage text rarely forms valid multibyte UTF-8. Ties leave the file alone.

When the migration cannot be written the append handle uses the legacy codepage,
and errors = "replace" quietly turned characters it cannot hold into question
marks while write() still reported success. That path now escapes to \uXXXX
instead, which is ASCII, so every codepage holds it and json.loads returns the
exact characters. Nothing needs replacing, so errors = "strict" is safe.

stream_installer runs sys.executable, so its output is now decoded as UTF-8 by
utf8_child_env rather than read as the ANSI codepage.

* Only rewrite a shard we can attribute, and append ASCII when we cannot

latin-1 was doing too much work. It reads any byte, so it gave a moved shard a
reading, but it is the right text only for cp1252: cp1251 Привет came back as
Ïðèâåò and the rewrite made that permanent. The codepage is now trusted only
when it is the locale's, and an untrusted reading is never written back.

That leaves three cases where the file holds bytes UTF-8 cannot read and we are
not converting it: no codepage to attribute it to, ambiguous lines outvoting the
unambiguous ones, and a preload that could not read the file at all. All three
used to append UTF-8 into it. They now append pure ASCII, which every
ASCII-compatible codepage stores identically, so the file keeps decoding exactly
as it did and no record is lost.

Keys from the two readings are also kept apart. A damaged line in a healthy
shard was marked seen through its codepage reading, so the retry that would have
replaced the unreadable record was refused as a duplicate.

* Let the flash-attn install stub take the kwargs the installer now passes

_run_kwargs gained encoding and errors, so the one stub in this file that
spelled its signature out rejected the call. The other four here already take
**kwargs; this one now matches.

* Do not let a stuck temp file mask the migration failure

unlink() on the failure path could raise in its own right, on a stale
.utf8.tmp directory or a temp another process holds. That escaped the
constructor instead of returning False, so the caller never reached the ASCII
append fallback that keeps the shard single-encoding.

The pip fallback in install_wheel also spawns a Python child, so it gets
utf8_child_env like the probe above it already had. The uv and nvidia-smi
children are native binaries, where PYTHONIOENCODING would do nothing.

* Stop converting legacy shards; the encoding that wrote them is unknowable

trusted only ever meant that the bytes parse under this machine's codepage,
which for a single-byte codepage is nearly always true. A cp1251 shard opened on
a cp1252 Windows box decodes cleanly and would have been rewritten with Привет
as Ïðèâåò. That is the fourth way this rewrite could corrupt a shard, and the
common cause is that a file's encoding cannot be recovered from its bytes.

So the rewrite is gone. The shard is left exactly as found, and appends are pure
ASCII whenever it holds bytes UTF-8 cannot read, which is what actually
delivered the no-mixed-encoding guarantee the rewrite was added for. Dedup keys
still come from whichever reading parses, since ids are ASCII either way.

This also removes the temp file, so there is no longer any file mode or ACL to
carry across.

* Scan the sandbox shim; it is shipped code, not a build artifact

sandbox_site is on the sandboxed child's PYTHONPATH for every Python run
(tools.py:332, 2660), so excluding it let two unannotated text calls through in
code we ship. Both read and write the remap sidecar, which holds file paths.

The exclusion list is meant for build output only, so the directory comes off
it and the two calls name their encoding.

* Force the worker's pip children to UTF-8, and read DBCS keys with a DBCS codec

The three installer calls run sys.executable -m pip with an inherited
environment, so the parent decoded UTF-8 while the child emitted the ANSI
codepage. They now go through utf8_child_env like the other Python children.

Two tests asserted no env kwarg was passed as a stand-in for no HIP flag being
injected. They now assert the flag itself, which is the guarantee they were
written for and does not depend on how the env is delivered.

Separately, latin-1 cannot stand in for a double-byte codepage while recovering
dedup keys: cp932 表 is 95 5C, and the trail byte reads as a JSON backslash, so
the record failed to parse and its id was forgotten, appending a duplicate on
resume. cp932, cp936, cp949 and cp950 are tried too. The reading is still only
ever used for keys, which are ASCII and identical whichever codec parses.

* Require more than one legacy line before trusting its dedup keys

A shard whose valid records are all ASCII casts no UTF-8 votes, so a single
damaged line won the vote by itself, its key was remembered, and the retry that
would have replaced the unreadable record was refused.

One such line is genuinely undecidable: a legacy record with one accented
character and an ASCII record with one stray byte are the same shape. Reading it
as damage costs a duplicate; reading it as legacy loses the record for good.
Only one of those is recoverable, so it is now read as damage.

A real legacy shard has a legacy line for every record carrying an umlaut, so
its dedup is unaffected.

* Append ASCII whenever the shard already holds non-ASCII bytes

The gate asked whether any line was undecodable as UTF-8, which misses a shard
where every legacy line happens to be valid UTF-8 too. A cp1251 shard of Р°
records is bytes D0 B0 throughout, so appending 世界 as UTF-8 left a file where
cp1251 reads the old records correctly and the new one as mojibake, and UTF-8
does the reverse. No single decoding recovered the whole scrape.

The gate is now simply whether the shard holds any non-ASCII byte at all, which
covers both cases and is easier to reason about: if what is already there reads
differently under different encodings, do not add more bytes that do.

Appending ASCII costs only \uXXXX escapes, which json.loads turns back into the
exact characters, and it leaves the new record correct under either reading.

* Skip the two Linux-gated flash-attn tests off Linux

_should_try_runtime_flash_attn_install ends in sys.platform.startswith(
"linux"), and the threshold test one line above already asserts exactly that,
so the two tests that drive _ensure_flash_attn_for_long_context past the gate
cannot pass anywhere else: the call returns before it reports a status. They
were written on Linux and only surface once the suite actually runs on Windows
or macOS, where both fail on an empty status list. This PR is about making the
backend behave on Windows, so its own suite should be runnable there.

* Fail closed when a KFD topology node does not decode

This PR pins that read to utf-8, which turns an undecodable byte into
UnicodeDecodeError. That is a ValueError, not an OSError, so it slips past the
handler one line below and escapes a helper whose docstring promises to fail
closed on any unreadable node. The caller would then lose the whole HIP-order
map on a machine that has AMD GPUs, and the reason the helper fails closed is
that dropping a node shifts every later ordinal and lets a similar-capacity GPU
pass the total-size guard while showing another card's usage.

Widening the handler is the same one-line change main already made in #7487, so
the two agree and the eventual merge is clean.

* Tighten the comments added in this branch

* Treat an undecodable marker and undecodable metadata as malformed, not fatal

Two more places where pinning the decode changed the failure mode. A
UnicodeDecodeError is a ValueError, so neither `except OSError` nor
`except (JSONDecodeError, OSError)` catches it, and both sites had a documented
fallback that stopped being reached.

An undecodable .transport marker used to read as an unknown value, and the
caller then safely purged and restarted the partial download. It now aborts
prepare_cache_for_transport instead, so the transfer fails rather than retrying.

Undecodable .meta.json used to fall back to the file's own name, the same way
invalid JSON does. It now aborts URI construction for the entire unstructured
seed, so one corrupt byte in original_filename takes out the whole dataset.

Both handlers are widened, matching the KFD fix earlier on this branch.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Widen two more decode guards, and pin the kernel installer's pipe

Same shape as the ones already fixed here: the read was pinned to UTF-8 while
the handler around it still only catches OSError, and UnicodeDecodeError is a
ValueError.

hf_cache_snapshot_dir answers whether a model is already on disk, and the
offline embedding checks turn a raise into a 500. A torn refs/main used to
decode into a nonsense commit and miss the snapshot dir; it now skips that cache
root and keeps looking. _remove_pid_file runs first in _graceful_shutdown, so a
corrupt studio.pid raising there abandoned the inference, export, training and
tunnel children the rest of that function exists to kill.

ssm_runtime's source-build path builds its subprocess kwargs in a dict and
splats them through _run_with_heartbeat, so neither the encoding guard nor the
earlier sweep saw the text = True in it: pip's output was still decoded with the
Windows ANSI codepage, where a non-ASCII path or a compiler diagnostic mojibakes
or raises over an install that was going fine. It now pins the same
utf-8/replace pair install_wheel uses, and the HIP branch extends that env
rather than replacing it. The guard learned the dict-literal shape and reddens
on the old code (ssm_runtime.py:253).

* Tighten the comments around the UTF-8 text I/O pins

Collapse the multi-line rationales added with the encoding pins down to a
line or two each, drop what the code already says, and use one wording for
the repeated child-env note.

* Do not let an unreadable bootstrap password stop startup, and narrow the kwargs guard

ensure_default_admin calls _load_bootstrap_password for every existing admin and
the lifespan calls that with no handler, so pinning the decode turned a damaged
or pre-pin .bootstrap_password file into a backend that will not start. We write
that file ourselves in UTF-8, so a byte that will not decode belongs to a file
whose plaintext is worthless anyway; it now reads as no bootstrap password, the
same answer as an absent file. A readable one still loads.

The new kwargs check also judged every dict literal in the tree, so an unrelated
payload carrying "text": True would have been reported as subprocess
configuration with a misleading message, and a dict that fills in its encoding on
a later line would have been reported too. It now only judges a dict that
actually reaches a call, either splatted through a name or written at the call
site, and treats a later kw["encoding"] assignment as satisfying it. The
ssm_runtime shape it was written for is still caught, and a test pins both
directions.

* Stop reading a UTF-8 record a second time

_read_line always parsed the line under the codepage as well, even when it had
already read as UTF-8. Both callers take the UTF-8 reading when there is one and
never look at the other, so on a healthy shard the second parse is pure waste,
and this file reads all of one on every resume of a scrape it expects to reach
gigabytes. Measured on 200,000 records, 76 MB: 1.96s before, 0.81s after, so the
double reading was costing 2.8x.

The early return is limited to a record, since the key lookup deliberately falls
through to the codepage reading when UTF-8 yields something that is not one. A
line UTF-8 cannot read still tries the codepage, latin-1 and the double-byte
encodings as before, which is what the second reading is for.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Pin the scanned source fixture's line endings

test_remote_code_scan_reads_non_ascii_sources compared a file's contents against
the string it wrote, but wrote it in text mode, so Windows translated the line
ends on the way out and the read back differed by a carriage return. That is the
writer's doing, not the encoding the test is about, and it was the one failure on
the Windows runner that belonged to this branch. The fixture now writes with
newline = "" so the bytes on disk are the string on every platform.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Trim the newer comments to their point

Shorten the widened-guard and state store notes added since the last pass,
and collapse the line-ending note on the scanned source fixture.

* Read the scraper checkpoint as UTF-8 only, never as a codepage

A checkpoint holds nothing but base64 cursors and booleans, so one written by
an older locale-encoded release is byte-identical to a UTF-8 one and already
reads back. The codepage fallback can therefore only ever contribute non-ASCII:
if a single-byte reading of the file were all ASCII, the UTF-8 read would have
succeeded first.

So the only file it changes the answer for is a damaged one, and there it turns
a safe reset into a resume on a mojibaked cursor. GitHub answers that with
INVALID_CURSOR_ARGUMENTS at HTTP 200, gh_client returns the partial document,
and the scraper reads zero nodes and an empty pageInfo, which marks the stream
done. Every later resume then skips it entirely.

Reading UTF-8 only restores the earlier behaviour of dropping a checkpoint that
will not decode, which re-scrapes from the first page while the writers dedup
the replay. The shard scan below keeps its codepage reading; those records do
carry non-ASCII.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Gate the remaining tilelang install tests to Linux

_tilelang_platform_supported() returns False off Linux, so _ensure_tilelang_backend
returns before the install and the subprocess mock these six assert on is never
called. They fail on macOS runners for that reason alone. The rest of the file
already carries this marker; these were missed.

* Gate the Windows-incompatible worker and ROCm tests

Two different gates, because the production code has two. The causal-conv1d and
flash-linear-attention installers bail out on sys.platform == 'win32' alone and
run everywhere else including macOS, so those cases get not_on_windows; marking
them linux_only would skip tests that legitimately pass off Linux. The DRM and
KFD readers return early unless platform.system() is Linux, and their fixtures
build a fake sysfs tree needing PCI addresses like 0000:00:02.0 as directory
names, which Windows cannot represent, so those get linux_only.

The two visible-utilization cases failed for a different reason: on Windows
get_visible_gpu_utilization takes the AMD adapter branch ahead of the torch
fallback under test, and probing it imports torch, which the runner lacks.
Stubbing that branch empty leaves every other platform unchanged.

* Treat unparseable JSON nesting as a parse failure, and guard os.fdopen

json.loads answers nesting it cannot descend with RecursionError, a
RuntimeError, so _parse let it escape where the catch-all it replaced
discarded the record. Both callers run _parse outside any further handler,
so one damaged checkpoint or shard line aborted the scraper at startup.

The encoding guard also missed os.fdopen, which is open() on a descriptor
and takes the same locale default in text mode. It flags exactly the two
text-mode calls that were left unencoded; the swap lock file's reader was
already pinned to UTF-8 while its writer still used the codepage.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Write the non-ASCII source fixture without a 3.10-only argument

Path.write_text() only grew newline in 3.10, and pyproject declares
requires-python >=3.9, so this raised TypeError there. open() takes the same
argument on every supported version and pins the bytes on disk the same way.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Tighten encoding comments

* Follow subprocess calls through callable aliases in the encoding guard

---------

Co-authored-by: Unsloth <michaelhan@Michaels-MacBook-Pro.local>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: danielhanchen <unslothshared@gmail.com>

---------

Co-authored-by: Unsloth <michaelhan@Michaels-MacBook-Pro.local>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: danielhanchen <unslothshared@gmail.com>
2026-07-28 21:27:27 -07:00

2531 lines
103 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-only
# Copyright 2026-present the Unsloth AI Inc. team. All rights reserved. See /studio/LICENSE.AGPL-3.0
"""Core inference backend."""
from unsloth import FastLanguageModel, FastVisionModel
from unsloth.chat_templates import get_chat_template
from transformers import TextIteratorStreamer, TextStreamer
from peft import PeftModel, PeftModelForCausalLM
import contextlib
import json
import sys
import torch
from pathlib import Path
from typing import Optional, Union, Generator, Tuple
from utils.models import ModelConfig, get_base_model_from_lora
from utils.paths import is_model_cached
from utils.transformers_dtype import dtype_kwargs
from utils.utils import format_error_message
from utils.hardware import (
get_device,
clear_gpu_cache,
log_gpu_memory,
get_device_map,
raise_if_offloaded,
get_visible_gpu_count,
)
from core.inference.audio_codecs import AudioCodecManager
from core.inference.runtime_context import runtime_context_length
from core.inference.message_content import content_to_text
from core.inference.chat_eos import (
chat_eos_repair,
resolve_chat_turn_end_eos_ids_using,
)
from core.inference.chat_template_helpers import (
ReasoningChannelNormalizer,
detect_reasoning_channel_markers,
detect_think_prefill,
)
from core.inference.presence_penalty import _make_presence_penalty_processor
from io import StringIO
import structlog
from loggers import get_logger
logger = get_logger(__name__)
class HarmonyTextStreamer:
"""Streaming text decoder for the gpt-oss harmony channel protocol.
gpt-oss emits multi-channel output via ``<|channel|>analysis<|message|>...``
/ ``<|channel|>final<|message|>...``. Plain skip_special_tokens streaming
glues channel names to content. This decodes with skip_special_tokens=False
and parses statefully: emit ``<think>`` on first analysis, stream analysis,
emit ``</think>`` on first final, stream final. Tracking per-channel lengths
avoids the delta-on-transformed bug where wrapping tags shift position.
Same put/end/iterator interface as TextIteratorStreamer.
"""
import re as _re
_HARMONY_RE = _re.compile(
r"<\|channel\|>(\w+)<\|message\|>(.*?)(?=<\|end\|>|<\|channel\|>|\Z)",
_re.DOTALL,
)
def __init__(
self,
tokenizer,
*,
skip_prompt: bool = True,
timeout: float = 0.2,
):
import queue
self.tokenizer = tokenizer
self.skip_prompt = skip_prompt
self.timeout = timeout
self._queue: queue.Queue = queue.Queue()
self._token_ids: list = []
self._prompt_len: int = 0
self._is_first_put: bool = True
self._stop: bool = False
# Stateful channel tracking avoids delta-on-transformed bugs
self._emitted_think_open: bool = False
self._emitted_think_close: bool = False
self._analysis_emitted: int = 0 # chars of analysis content emitted
self._final_emitted: int = 0 # chars of final content emitted
# put / end — called from the generation thread
def put(self, value):
"""Receive new token IDs from model.generate()."""
import torch
if isinstance(value, torch.Tensor):
# shape (batch, seq) — take first batch element
ids = value[0].tolist() if value.dim() > 1 else value.tolist()
elif isinstance(value, (list, tuple)):
ids = list(value)
else:
ids = [value]
if self._is_first_put and self.skip_prompt:
# First call is the full prompt; remember its length.
self._prompt_len = len(ids)
self._token_ids = list(ids)
self._is_first_put = False
return
self._token_ids.extend(ids)
# Decode only the generated part (after the prompt).
gen_ids = self._token_ids[self._prompt_len :]
raw = self.tokenizer.decode(gen_ids, skip_special_tokens = False)
self._process_incremental(raw)
def end(self):
"""Signal generation is complete."""
# Final decode to capture remaining content.
gen_ids = self._token_ids[self._prompt_len :]
if gen_ids:
raw = self.tokenizer.decode(gen_ids, skip_special_tokens = False)
self._process_incremental(raw)
# Close any open think tags.
if self._emitted_think_open and not self._emitted_think_close:
self._queue.put("</think>")
self._emitted_think_close = True
self._stop = True
self._queue.put(None) # sentinel
# Iterator interface — consumed by the streaming loop
def __iter__(self):
return self
def __next__(self):
from queue import Empty
while True:
try:
val = self._queue.get(timeout = self.timeout)
except Empty:
if self._stop:
raise StopIteration
raise # propagate Empty so caller can check thread liveness
if val is None:
raise StopIteration
return val
# Stateful incremental harmony protocol parsing
def _process_incremental(self, raw: str) -> None:
"""Parse harmony channels and emit per-channel deltas (tracked by length, not whole-text diff)."""
# If raw has <|channel|> but no complete channel+message pair yet, buffer.
has_channel_token = "<|channel|>" in raw
matches = list(self._HARMONY_RE.finditer(raw))
if has_channel_token and not matches:
# Partial harmony markup still building — wait for more tokens.
return
if not has_channel_token and not matches:
return
for m in matches:
channel = m.group(1).lower()
content = m.group(2)
if channel == "analysis":
if not self._emitted_think_open:
self._queue.put("<think>")
self._emitted_think_open = True
new_content = content[self._analysis_emitted :]
if new_content:
self._analysis_emitted = len(content)
self._queue.put(new_content)
elif channel in ("final", "assistant"):
if self._emitted_think_open and not self._emitted_think_close:
self._queue.put("</think>")
self._emitted_think_close = True
new_content = content[self._final_emitted :]
if new_content:
self._final_emitted = len(content)
self._queue.put(new_content)
class ReasoningTextIteratorStreamer(TextIteratorStreamer):
"""TextIteratorStreamer that preserves native channel tokens until parsed."""
def __init__(
self,
tokenizer,
*,
markers: tuple[str, str],
skip_prompt: bool = True,
timeout: float = 0.2,
cancel_event = None,
**decode_kwargs,
):
decode_kwargs["skip_special_tokens"] = False
super().__init__(tokenizer, skip_prompt = skip_prompt, timeout = timeout, **decode_kwargs)
self._normalizer = ReasoningChannelNormalizer(*markers)
self._cancel_event = cancel_event
self._aborted = False
def abort(self):
"""Mark generation as failed so ``end`` drains without closing."""
self._aborted = True
def on_finalized_text(
self,
text: str,
stream_end: bool = False,
):
"""Queue canonical deltas, closing only on natural stream completion."""
delta = self._normalizer.feed(text)
if delta:
self.text_queue.put(delta, timeout = self.timeout)
if stream_end:
cancelled = self._aborted or (
self._cancel_event is not None and self._cancel_event.is_set()
)
tail = self._normalizer.drain() if cancelled else self._normalizer.finish()
if tail:
self.text_queue.put(tail, timeout = self.timeout)
self.text_queue.put(self.stop_signal, timeout = self.timeout)
class _GenerationThreadError(RuntimeError):
"""Generation worker failures that should propagate through stream routes."""
class InferenceBackend:
"""Unified inference backend supporting text, vision, and LoRA models"""
def __init__(self):
self.models = {}
self.active_model_name = None
self.loading_models = set()
self.loaded_local_models = [] # [(display_name, path), ...]
from core.inference.defaults import get_default_models
self.default_models = get_default_models()
self.device = get_device().value
self._audio_codec_manager = AudioCodecManager()
# _generation_lock serializes model.generate(). Plain Lock (NOT RLock):
# RLock reentrancy would let concurrent compare-mode requests race on
# the GPU. Acquired by the background generation thread, not the event-loop.
import threading
self._generation_lock = threading.Lock()
self._model_state_lock = threading.Lock()
logger.info(f"InferenceBackend initialized on {self.device}")
@staticmethod
def _normalize_top_k(top_k: int) -> int:
# API uses -1 to disable top-k; transformers uses 0.
return 0 if top_k < 0 else top_k
def _resolve_chat_eos(self, model_name: str) -> None:
"""Resolve this chat model's assistant-turn-end stop tokens once at load,
cache them in model_info, and repair generation_config so every
``.generate()`` path stops at the turn boundary.
Some checkpoints (e.g. Qwen3.5 / Qwen3.6 small chat models) end turns with
``<|im_end|>`` but ship ``config.eos_token_id = <|endoftext|>`` and no
``generation_config.json``, so paths that read ``generation_config`` (the
vision path, tool loops) run past the turn and loop. Turn-end markers are
derived from the chat_template (see chat_eos.resolve_chat_turn_end_eos_ids),
so base/coder models and harmony templates are left untouched.
"""
info = self.models.get(model_name) or {}
model = info.get("model")
container = info.get("tokenizer")
tokenizer = getattr(container, "tokenizer", container) # unwrap processors
if model is None or tokenizer is None:
return
# Vision models carry the chat_template on the processor, not the inner
# tokenizer. Read markers from whichever has one, but resolve ids on the
# generation tokenizer, else the vision path misses the turn-end token.
template_source = container if getattr(container, "chat_template", None) else tokenizer
try:
turn_end_ids = resolve_chat_turn_end_eos_ids_using(template_source, tokenizer)
except Exception as e: # never block a load on eos resolution
logger.warning("Chat turn-end eos resolution failed for %s: %s", model_name, e)
return
info["chat_turn_end_eos_ids"] = turn_end_ids
gen = getattr(model, "generation_config", None)
if gen is None:
return
repaired = chat_eos_repair(gen.eos_token_id, turn_end_ids)
if repaired is None:
return
previous = gen.eos_token_id
gen.eos_token_id = repaired
logger.info(
"Repaired generation_config.eos_token_id for %s: %s -> %s",
model_name,
previous,
repaired,
)
def load_model(
self,
config: ModelConfig,
max_seq_length: int = 2048,
dtype = None,
load_in_4bit: bool = True,
hf_token: Optional[str] = None,
trust_remote_code: bool = False,
gpu_ids: Optional[list[int]] = None,
) -> bool:
"""Load any model: base, LoRA adapter, text, or vision."""
# Keep the token so the native-template fallback can fetch a
# gated model's repo template later during generation.
self._hf_token = hf_token
# GGUF uses max_seq_length=0 as "model default"; Unsloth crashes on it.
if max_seq_length <= 0:
max_seq_length = 2048
try:
model_name = config.identifier
# Already loaded?
if model_name in self.models and self.models[model_name].get("model"):
logger.info(f"Model {model_name} already loaded")
if hf_token:
self.models[model_name]["hf_token"] = hf_token
self.active_model_name = model_name
return True
# Currently loading?
if model_name in self.loading_models:
logger.info(f"Model {model_name} is already being loaded")
return False
self.loading_models.add(model_name)
device_map = get_device_map(gpu_ids)
logger.info(
f"Using device_map='{device_map}' ({get_visible_gpu_count()} GPU(s) visible)"
)
self.models[model_name] = {
# Per-model token: the native-template fallback must use the
# token this model was loaded with, not whichever loaded last.
"hf_token": hf_token,
# Per-model consent: the native-template reload must re-use the
# exact trust_remote_code this model (and a LoRA's base) was loaded
# with, so a custom-code tokenizer repo can be re-fetched without
# executing any code the user did not already consent to.
"trust_remote_code": trust_remote_code,
"is_vision": config.is_vision,
"is_lora": config.is_lora,
"is_audio": config.is_audio,
"audio_type": config.audio_type,
"has_audio_input": config.has_audio_input,
"model_path": config.path,
"base_model": config.base_model if config.is_lora else None,
"loaded_adapters": {},
"active_adapter": None,
}
# ── Audio model loading path ──────────────────────────
if config.is_audio:
audio_type = config.audio_type
adapter_info = " (LoRA adapter)" if config.is_lora else ""
logger.info(f"Loading audio ({audio_type}) model{adapter_info}: {model_name}")
log_gpu_memory(f"Before loading {model_name}")
if audio_type == "csm":
from unsloth import FastModel
from transformers import CsmForConditionalGeneration
model, processor = FastModel.from_pretrained(
config.path,
auto_model = CsmForConditionalGeneration,
load_in_4bit = False,
device_map = device_map,
token = hf_token if hf_token and hf_token.strip() else None,
trust_remote_code = trust_remote_code,
)
FastModel.for_inference(model)
self.models[model_name]["model"] = model
self.models[model_name]["tokenizer"] = processor
self.models[model_name]["processor"] = processor
elif audio_type == "bicodec":
import os
from unsloth import FastModel
if config.is_lora and config.base_model:
# LoRA adapter: base_model is .../Spark-TTS-0.5B/LLM;
# BiCodec weights live in the parent dir.
base_path = config.base_model
if os.path.isdir(base_path):
abs_repo_path = os.path.abspath(os.path.dirname(base_path))
else:
# base_model is an HF ID — download it.
from huggingface_hub import snapshot_download
local_dir = base_path.split("/")[-1]
repo_path = snapshot_download(base_path, local_dir = local_dir)
abs_repo_path = os.path.abspath(repo_path)
logger.info(
f"Spark-TTS LoRA: loading adapter from {config.path}, BiCodec from {abs_repo_path}"
)
model, tokenizer = FastModel.from_pretrained(
config.path,
dtype = torch.float32,
load_in_4bit = False,
device_map = device_map,
token = hf_token if hf_token and hf_token.strip() else None,
trust_remote_code = trust_remote_code,
)
else:
# Base model: download full HF repo, load from /LLM subfolder
from huggingface_hub import snapshot_download
hf_repo = config.path
local_dir = hf_repo.split("/")[-1]
repo_path = snapshot_download(hf_repo, local_dir = local_dir)
abs_repo_path = os.path.abspath(repo_path)
llm_path = os.path.join(abs_repo_path, "LLM")
logger.info(
f"Spark-TTS: downloaded repo to {repo_path}, loading LLM from {llm_path}"
)
model, tokenizer = FastModel.from_pretrained(
llm_path,
dtype = torch.float32,
load_in_4bit = False,
device_map = device_map,
token = hf_token if hf_token and hf_token.strip() else None,
trust_remote_code = trust_remote_code,
)
FastModel.for_inference(model)
self.models[model_name]["model"] = model
self.models[model_name]["tokenizer"] = tokenizer
self.models[model_name]["model_repo_path"] = abs_repo_path
elif audio_type == "dac":
# OuteTTS uses FastModel (not FastLanguageModel)
from unsloth import FastModel
model, tokenizer = FastModel.from_pretrained(
config.path,
max_seq_length = max_seq_length,
load_in_4bit = False,
device_map = device_map,
token = hf_token if hf_token and hf_token.strip() else None,
trust_remote_code = trust_remote_code,
)
FastModel.for_inference(model)
self.models[model_name]["model"] = model
self.models[model_name]["tokenizer"] = tokenizer
elif audio_type == "whisper":
# Whisper ASR — uses FastModel with WhisperForConditionalGeneration
from unsloth import FastModel
from transformers import WhisperForConditionalGeneration
model, tokenizer = FastModel.from_pretrained(
config.path,
auto_model = WhisperForConditionalGeneration,
whisper_language = "English",
whisper_task = "transcribe",
load_in_4bit = False,
device_map = device_map,
token = hf_token if hf_token and hf_token.strip() else None,
trust_remote_code = trust_remote_code,
)
FastModel.for_inference(model)
model.eval()
# ASR pipeline (per notebook)
from transformers import pipeline as hf_pipeline
whisper_pipe = hf_pipeline(
"automatic-speech-recognition",
model = model,
tokenizer = tokenizer.tokenizer,
feature_extractor = tokenizer.feature_extractor,
processor = tokenizer,
return_language = True,
**dtype_kwargs(torch.float16),
)
self.models[model_name]["model"] = model
self.models[model_name]["tokenizer"] = tokenizer
self.models[model_name]["whisper_pipeline"] = whisper_pipe
else:
# SNAC (Orpheus) uses FastLanguageModel
model, tokenizer = FastLanguageModel.from_pretrained(
model_name = config.path,
max_seq_length = max_seq_length,
load_in_4bit = False,
device_map = device_map,
token = hf_token if hf_token and hf_token.strip() else None,
trust_remote_code = trust_remote_code,
)
FastLanguageModel.for_inference(model)
self.models[model_name]["model"] = model
self.models[model_name]["tokenizer"] = tokenizer
# Load external codec for TTS audio types
# (Whisper is ASR, audio_vlm is audio input — neither needs one)
if audio_type not in ("whisper", "audio_vlm"):
model_repo_path = self.models[model_name].get("model_repo_path")
self._audio_codec_manager.load_codec(
audio_type, self.device, model_repo_path = model_repo_path
)
# Reject CPU/disk offload for audio models too
raise_if_offloaded(self.models[model_name]["model"], device_map, "Inference")
self.models[model_name]["context_length"] = runtime_context_length(
self.models[model_name].get("model"),
max_seq_length,
)
self.active_model_name = model_name
self.loading_models.discard(model_name)
logger.info(f"Successfully loaded audio model: {model_name}")
log_gpu_memory(f"After loading {model_name}")
return True
model_type = "vision" if config.is_vision else "text"
adapter_info = " (LoRA adapter)" if self.models[model_name]["is_lora"] else ""
logger.info(f"Loading {model_type} model{adapter_info}: {model_name}")
log_gpu_memory(f"Before loading {model_name}")
# Same load path for base models and LoRA adapters
if config.is_vision:
# Vision model (or vision LoRA adapter)
model, processor = FastVisionModel.from_pretrained(
model_name = config.path, # Can be base model OR LoRA adapter path
max_seq_length = max_seq_length,
dtype = dtype,
load_in_4bit = load_in_4bit,
device_map = device_map,
token = hf_token if hf_token and hf_token.strip() else None,
trust_remote_code = trust_remote_code,
)
FastVisionModel.for_inference(model)
# FastVisionModel may return a raw tokenizer instead of a
# Processor for some models (e.g. Gemma-3); load the real one.
from transformers import ProcessorMixin
if not (
isinstance(processor, ProcessorMixin) or hasattr(processor, "image_processor")
):
# LoRA adapters: use base model. Local merged exports: read base from export_metadata.json.
processor_source = config.base_model if config.is_lora else config.identifier
if not config.is_lora and config.is_local:
_meta_path = Path(config.path) / "export_metadata.json"
try:
if _meta_path.exists():
_meta = json.loads(_meta_path.read_text(encoding = "utf-8-sig"))
if _meta.get("base_model"):
processor_source = _meta["base_model"]
except Exception:
pass
logger.warning(
f"FastVisionModel returned {type(processor).__name__} (no image_processor) "
f"for '{model_name}' — loading proper processor from '{processor_source}'"
)
from transformers import AutoProcessor
processor = AutoProcessor.from_pretrained(
processor_source,
token = hf_token if hf_token and hf_token.strip() else None,
trust_remote_code = trust_remote_code,
)
logger.info(f"Loaded {type(processor).__name__} from {processor_source}")
self.models[model_name]["model"] = model
self.models[model_name]["tokenizer"] = processor
self.models[model_name]["processor"] = processor
else:
# Text model (or text LoRA adapter)
model, tokenizer = FastLanguageModel.from_pretrained(
model_name = config.path, # Can be base model OR LoRA adapter path
max_seq_length = max_seq_length,
dtype = dtype,
load_in_4bit = load_in_4bit,
device_map = device_map,
token = hf_token if hf_token and hf_token.strip() else None,
trust_remote_code = trust_remote_code,
)
FastLanguageModel.for_inference(model)
self.models[model_name]["model"] = model
self.models[model_name]["tokenizer"] = tokenizer
raise_if_offloaded(self.models[model_name]["model"], device_map, "Inference")
self.models[model_name]["context_length"] = runtime_context_length(
self.models[model_name].get("model"),
max_seq_length,
)
self._resolve_chat_eos(model_name)
self._load_chat_template_info(model_name)
self.active_model_name = model_name
self.loading_models.discard(model_name)
logger.info(f"Successfully loaded model: {model_name}")
log_gpu_memory(f"After loading {model_name}")
return True
except Exception as e:
logger.error(f"Failed to load model: {e}")
error_msg = format_error_message(e, config.identifier)
# Cleanup on failure
if model_name in self.models:
del self.models[model_name]
self.loading_models.discard(model_name)
raise Exception(error_msg)
def unload_model(self, model_name: str) -> bool:
"""Remove a model from the registry and clear GPU memory."""
if model_name in self.models:
try:
# Clean up codecs for audio models
if self.models[model_name].get("is_audio"):
self._audio_codec_manager.unload()
logger.info(f"Unloading model '{model_name}' from memory.")
del self.models[model_name]
# Clear the active model if it was the one unloaded
if self.active_model_name == model_name:
self.active_model_name = None
clear_gpu_cache()
# Drop stale compiled cache for the next model. On spawn platforms,
# preserve trainer files so concurrent dataset.map() workers can import them.
import sys as _sys
from utils.cache_cleanup import clear_unsloth_compiled_cache
_preserve = ["Unsloth*Trainer.py"] if _sys.platform in ("win32", "darwin") else None
clear_unsloth_compiled_cache(preserve_patterns = _preserve)
logger.info(f"Model '{model_name}' successfully unloaded.")
return True
except Exception as e:
logger.error(f"Error while unloading model '{model_name}': {e}")
return False
else:
logger.warning(
f"Attempted to unload model '{model_name}', but it was not found in the registry."
)
return True
def revert_to_base_model(self, base_model_name: str) -> bool:
"""Revert the model to its pristine base state by unloading and
deleting all adapter configurations."""
if base_model_name not in self.models:
return False
model = self.models[base_model_name].get("model")
try:
# Unload adapter weights if model is a PeftModel.
if isinstance(model, (PeftModel, PeftModelForCausalLM)):
logger.info(f"Unloading LoRA adapters from '{base_model_name}'...")
unwrapped_base_model = model.unload()
self.models[base_model_name]["model"] = unwrapped_base_model
model = unwrapped_base_model
# model.unload() can leave a peft_config; removing it avoids
# "multiple adapters" warnings on the next from_pretrained().
if hasattr(model, "peft_config"):
del model.peft_config
logger.info(f"Model '{base_model_name}' reverted to clean base state.")
return True
except Exception as e:
logger.error(f"Failed to revert model to base state: {e}")
import traceback
logger.error(traceback.format_exc())
return False
def load_for_eval(
self,
lora_path: str,
max_seq_length: int = 2048,
dtype = None,
load_in_4bit: bool = True,
hf_token: Optional[str] = None,
gpu_ids: Optional[list[int]] = None,
) -> Tuple[bool, Optional[str], Optional[str]]:
"""Ensure the base model and the given adapter are loaded.
Idempotent and handles all states correctly.
"""
try:
from utils.models import ModelConfig
lora_config = ModelConfig.from_lora_path(lora_path, hf_token)
if not lora_config:
return False, None, None
base_model_name = lora_config.base_model
# 1. Load the base model if not already in memory
if base_model_name not in self.models or not self.models[base_model_name].get("model"):
logger.info(f"Base model '{base_model_name}' not loaded, loading now.")
base_config = ModelConfig.from_ui_selection(base_model_name, None, is_lora = False)
if not self.load_model(
base_config,
max_seq_length,
dtype,
load_in_4bit,
hf_token,
gpu_ids = gpu_ids,
):
return False, None, None
self.active_model_name = base_model_name
# 2. Derive adapter name from the user's selection
adapter_name = lora_path.split("/")[-1].replace(".", "_")
# 3. Ensure this adapter is loaded (load_adapter only reads from
# disk if the model doesn't already have it).
adapter_success = self.load_adapter(
base_model_name = base_model_name,
adapter_path = lora_path,
adapter_name = adapter_name,
)
if not adapter_success:
return False, base_model_name, None
# 4. Return the verified adapter name for the UI.
return True, base_model_name, adapter_name
except Exception as e:
logger.error(f"Error during load_for_eval: {e}")
import traceback
logger.error(traceback.format_exc())
return False, None, None
def load_adapter(self, base_model_name: str, adapter_path: str, adapter_name: str) -> bool:
"""Load an adapter onto the model only if not already attached."""
model = self.models[base_model_name].get("model")
# Most reliable check: adapter name already in the model's config.
if hasattr(model, "peft_config") and adapter_name in model.peft_config:
logger.info(
f"Adapter '{adapter_name}' is already attached to the model. Skipping load."
)
return True
try:
logger.info(
f"Loading new adapter '{adapter_name}' from '{adapter_path}' onto {base_model_name}"
)
model.load_adapter(adapter_path, adapter_name = adapter_name)
# Update the registry only after a successful load.
if "loaded_adapters" not in self.models[base_model_name]:
self.models[base_model_name]["loaded_adapters"] = {}
self.models[base_model_name]["loaded_adapters"][adapter_name] = adapter_path
total_adapters = len(getattr(model, "peft_config", {}))
logger.info(
f"Adapter '{adapter_name}' loaded successfully. (Total unique adapters on model: {total_adapters})"
)
return True
except Exception as e:
logger.error(f"Failed to load adapter '{adapter_name}': {e}")
return False
def set_active_adapter(self, base_model_name: str, adapter_name: str) -> bool:
"""Set the active adapter for generation."""
model = self.models[base_model_name].get("model")
try:
logger.info(f"Setting active adapter to: '{adapter_name}'")
model.set_adapter(adapter_name)
self.models[base_model_name]["active_adapter"] = adapter_name
return True
except Exception as e:
# Catches "adapter not found" if something goes wrong.
logger.error(f"Failed to set active adapter to '{adapter_name}': {e}")
return False
def _apply_adapter_state(self, use_adapter: Optional[Union[bool, str]]) -> None:
"""Apply adapter state before generation (must hold _generation_lock).
Toggles PEFT enable/disable_adapter_layers (non-destructive, no reload).
use_adapter: None = no change, False = base model, True = current adapter,
str = named adapter.
"""
if use_adapter is None:
return
base = self.active_model_name
if not base or base not in self.models:
return
model_info = self.models[base]
model = model_info.get("model")
if model is None:
return
if use_adapter is False:
# Disable LoRA layers -> base model output.
if isinstance(model, (PeftModel, PeftModelForCausalLM)):
logger.info(
f"Compare mode: disabling adapters on '{base}' for base model generation"
)
model.base_model.disable_adapter_layers()
else:
logger.info(f"Compare mode: model '{base}' is not a PeftModel, already base")
elif use_adapter is True:
# Re-enable LoRA layers -> adapter output.
if isinstance(model, (PeftModel, PeftModelForCausalLM)):
logger.info(f"Compare mode: enabling adapters on '{base}' for LoRA generation")
model.base_model.enable_adapter_layers()
else:
logger.warning("use_adapter=true but model is not a PeftModel")
elif isinstance(use_adapter, str):
# Enable adapters and set the named one active.
if isinstance(model, (PeftModel, PeftModelForCausalLM)):
logger.info(f"Compare mode: enabling adapter '{use_adapter}' on '{base}'")
model.base_model.enable_adapter_layers()
self.set_active_adapter(base, use_adapter)
else:
logger.warning(f"use_adapter='{use_adapter}' but model is not a PeftModel")
def generate_with_adapter_control(
self,
use_adapter: Optional[Union[bool, str]] = None,
cancel_event = None,
**gen_kwargs,
) -> Generator[str, None, None]:
"""Thread-safe generation with optional adapter toggling.
Adapter toggle + model.generate() are serialized by _generation_lock in
the background thread, avoiding the RLock-reentrant race when two async
SSE handlers share one event-loop thread. use_adapter: see _apply_adapter_state.
"""
yield from self._generate_chat_response_inner(
cancel_event = cancel_event, _adapter_state = use_adapter, **gen_kwargs
)
def generate_chat_completion_with_tools(
self,
messages: list,
tools: list,
system_prompt: str = "",
temperature: float = 0.7,
top_p: float = 0.9,
top_k: int = 40,
min_p: float = 0.0,
max_new_tokens: int = 2048,
repetition_penalty: float = 1.0,
cancel_event = None,
enable_thinking: Optional[bool] = None,
reasoning_effort: Optional[str] = None,
preserve_thinking: Optional[bool] = None,
max_tool_iterations: int = 25,
auto_heal_tool_calls: bool = True,
nudge_tool_calls: Optional[bool] = None,
tool_call_timeout: int = 300,
session_id: Optional[str] = None,
thread_id: Optional[str] = None,
rag_scope: Optional[dict] = None,
presence_penalty: float = 0.0,
reasoning_prefilled: bool = False,
):
"""Run an agentic tool loop on top of ``generate_chat_response``.
Yields the same event-dict protocol as the GGUF path so the route
layer can stream both backends through one helper. Each event is one of:
* ``{"type": "status", "text": ...}``
* ``{"type": "content", "text": cumulative_text}``
* ``{"type": "tool_start", "tool_name", "tool_call_id", "arguments"}``
* ``{"type": "tool_end", "tool_name", "tool_call_id", "result"}``
"""
from core.inference.safetensors_agentic import run_safetensors_tool_loop
from core.inference.tools import execute_tool
def _single_turn(conv: list, *, active_tools: Optional[list[dict]] = None):
# conv already has the system message -- avoid double-prepend.
# `active_tools` is supplied by run_safetensors_tool_loop so one-shot
# tools such as render_html can be removed from later same-response prompts.
turn_tools = active_tools if active_tools is not None else tools
yield from self._generate_chat_response_inner(
messages = conv,
system_prompt = "",
temperature = temperature,
top_p = top_p,
top_k = top_k,
min_p = min_p,
max_new_tokens = max_new_tokens,
repetition_penalty = repetition_penalty,
cancel_event = cancel_event,
tools = turn_tools,
enable_thinking = enable_thinking,
reasoning_effort = reasoning_effort,
preserve_thinking = preserve_thinking,
presence_penalty = presence_penalty,
)
initial = list(messages)
if system_prompt:
initial = [{"role": "system", "content": system_prompt}] + initial
yield from run_safetensors_tool_loop(
single_turn = _single_turn,
messages = initial,
tools = tools,
execute_tool = execute_tool,
cancel_event = cancel_event,
auto_heal_tool_calls = auto_heal_tool_calls,
nudge_tool_calls = nudge_tool_calls,
max_tool_iterations = max_tool_iterations,
tool_call_timeout = tool_call_timeout,
session_id = session_id,
thread_id = thread_id,
rag_scope = rag_scope,
reasoning_prefilled = reasoning_prefilled,
)
def generate_chat_response(
self,
messages: list,
system_prompt: str,
image = None,
temperature: float = 0.7,
top_p: float = 0.9,
top_k: int = 40,
min_p: float = 0.0,
max_new_tokens: int = 256,
repetition_penalty: float = 1.0,
cancel_event = None,
tools: Optional[list] = None,
enable_thinking: Optional[bool] = None,
reasoning_effort: Optional[str] = None,
preserve_thinking: Optional[bool] = None,
presence_penalty: float = 0.0,
) -> Generator[str, None, None]:
"""Generate response for text or vision models (lock held by background thread).
``tools`` / ``enable_thinking`` / ``reasoning_effort`` / ``preserve_thinking``
are forwarded into ``apply_chat_template`` so templates that understand them
(Qwen3, Llama 3.1+, gpt-oss harmony) advertise tool schemas / reasoning controls.
``presence_penalty`` matches the GGUF sampling path (0 disables it).
"""
yield from self._generate_chat_response_inner(
messages = messages,
system_prompt = system_prompt,
image = image,
temperature = temperature,
top_p = top_p,
top_k = top_k,
min_p = min_p,
max_new_tokens = max_new_tokens,
repetition_penalty = repetition_penalty,
cancel_event = cancel_event,
tools = tools,
enable_thinking = enable_thinking,
reasoning_effort = reasoning_effort,
preserve_thinking = preserve_thinking,
presence_penalty = presence_penalty,
)
def _generate_chat_response_inner(
self,
messages: list,
system_prompt: str = "",
image = None,
temperature: float = 0.7,
top_p: float = 0.9,
top_k: int = 40,
min_p: float = 0.0,
max_new_tokens: int = 256,
repetition_penalty: float = 1.0,
cancel_event = None,
_adapter_state = None,
tools: Optional[list] = None,
enable_thinking: Optional[bool] = None,
reasoning_effort: Optional[str] = None,
preserve_thinking: Optional[bool] = None,
presence_penalty: float = 0.0,
) -> Generator[str, None, None]:
"""Inner generation logic, called by generate_chat_response and
generate_with_adapter_control.
_adapter_state is passed to generate_stream/vision so the background
thread can toggle adapters under the generation lock.
"""
if not self.active_model_name:
raise RuntimeError("No active model")
model_info = self.models[self.active_model_name]
is_vision = model_info.get("is_vision", False)
tokenizer = model_info.get("tokenizer") or model_info.get("processor")
# Unwrap processor -> raw tokenizer for VLMs on the text path.
tokenizer = getattr(tokenizer, "tokenizer", tokenizer)
top_k = self._normalize_top_k(top_k)
if is_vision and image:
# Verify the stored processor can handle images; FastVisionModel may
# return a raw tokenizer instead of a ProcessorMixin (e.g. Gemma-3).
from transformers import ProcessorMixin
processor = model_info.get("processor")
has_image_processing = processor is not None and (
isinstance(processor, ProcessorMixin) or hasattr(processor, "image_processor")
)
if has_image_processing:
yield from self._generate_vision_response(
messages,
system_prompt,
image,
temperature,
top_p,
top_k,
min_p,
max_new_tokens,
repetition_penalty,
cancel_event = cancel_event,
presence_penalty = presence_penalty,
)
return
else:
logger.warning(
f"Model '{self.active_model_name}' is marked as vision but its processor "
f"({type(processor).__name__}) has no image_processor — "
f"falling back to text-only generation (image will be ignored)."
)
# Text path: messages are already in ChatML format from eval.py.
# Step 1: apply get_chat_template if model is in mapper.
try:
from utils.datasets import (
MODEL_TO_TEMPLATE_MAPPER,
get_tokenizer_chat_template,
)
model_name_lower = self.active_model_name.lower()
if model_name_lower in MODEL_TO_TEMPLATE_MAPPER:
template_name = MODEL_TO_TEMPLATE_MAPPER[model_name_lower]
logger.info(
f"Applying chat template '{template_name}' for {self.active_model_name}"
)
tokenizer = get_chat_template(
tokenizer,
chat_template = template_name,
)
# The mapper installs the effective template only now, at generate
# time, so re-resolve and UNION into the load-time cache (never
# overwrite). get_chat_template can return a remapped tokenizer
# (turn-end folded onto doc-eos) while generate_stream reads the
# original, so take marker strings from the mapped template but
# resolve their ids on the original.
try:
_gen_tok = model_info.get("tokenizer") or tokenizer
refreshed = resolve_chat_turn_end_eos_ids_using(
getattr(tokenizer, "tokenizer", tokenizer),
getattr(_gen_tok, "tokenizer", _gen_tok),
)
existing = model_info.get("chat_turn_end_eos_ids") or []
model_info["chat_turn_end_eos_ids"] = sorted(set(existing) | set(refreshed))
except Exception as e:
logger.warning(f"Could not refresh chat turn-end eos after template: {e}")
else:
logger.info(
f"No registered Unsloth template for {self.active_model_name}, using tokenizer default"
)
except Exception as e:
logger.warning(f"Could not apply get_chat_template: {e}")
# Step 2: format with tokenizer.apply_chat_template().
if system_prompt:
template_messages = [{"role": "system", "content": system_prompt}] + messages
else:
template_messages = messages
reasoning_channel_markers_resolved = False
try:
if not (hasattr(tokenizer, "chat_template") and tokenizer.chat_template):
raise ValueError(
f"Model '{self.active_model_name}' has no chat_template set in its "
f"tokenizer_config.json. This is usually a problem with the model's "
f"HuggingFace repository — it is missing a 'chat_template' key. "
f"Please use a model that includes a chat template, or manually set "
f"one via tokenizer.chat_template before inference."
)
reasoning_channel_markers = None
formatted_prompt = self._apply_chat_template_for_generation(
tokenizer,
template_messages,
tools = tools,
enable_thinking = enable_thinking,
reasoning_effort = reasoning_effort,
preserve_thinking = preserve_thinking,
)
# If tools were requested but the (possibly overridden) template ignored
# them, fall back to the model's native template (shared with MLX).
from core.inference.chat_template_helpers import (
render_with_native_template_fallback,
)
render_result = render_with_native_template_fallback(
formatted_prompt = formatted_prompt,
tokenizer = tokenizer,
model_info = model_info,
active_model_name = self.active_model_name,
messages = template_messages,
tools = tools,
enable_thinking = enable_thinking,
reasoning_effort = reasoning_effort,
preserve_thinking = preserve_thinking,
apply_fn = self._apply_chat_template_for_generation,
hf_token = model_info.get("hf_token"),
return_metadata = True,
)
formatted_prompt = render_result.prompt
reasoning_channel_markers = render_result.reasoning_channel_markers
reasoning_channel_markers_resolved = True
logger.debug(f"Formatted prompt: {formatted_prompt[:200]}...")
except Exception as e:
logger.error(f"Error applying chat template: {e}")
# Fall back to manual formatting
formatted_prompt = self.format_chat_prompt(messages, system_prompt)
reasoning_channel_markers = None
reasoning_channel_markers_resolved = True
# Step 3: generate
yield from self.generate_stream(
formatted_prompt,
temperature,
top_p,
top_k,
min_p,
max_new_tokens,
repetition_penalty,
cancel_event = cancel_event,
_adapter_state = _adapter_state,
presence_penalty = presence_penalty,
reasoning_channel_markers = reasoning_channel_markers,
reasoning_channel_markers_resolved = reasoning_channel_markers_resolved,
)
def _generate_vision_response(
self,
messages,
system_prompt,
image,
temperature,
top_p,
top_k,
min_p,
max_new_tokens,
repetition_penalty,
cancel_event = None,
presence_penalty: float = 0.0,
) -> Generator[str, None, None]:
"""Handle vision model generation with true token-by-token streaming."""
model_info = self.models[self.active_model_name]
model = model_info["model"]
processor = model_info["processor"]
# FastVisionModel may return a raw tokenizer (e.g. GemmaTokenizerFast)
# for some models. Safe unwrap for tokenize-only ops.
raw_tokenizer = getattr(processor, "tokenizer", processor)
# Extract user message
user_message = ""
if messages and messages[-1]["role"] == "user":
import re
user_message = content_to_text(messages[-1]["content"])
user_message = re.sub(r"<img[^>]*>", "", user_message).strip()
if not user_message:
user_message = "Describe this image." if image else "Hello"
# Prepare vision messages
if image:
user_msg = {
"role": "user",
"content": [
{"type": "image"},
{"type": "text", "text": user_message},
],
}
if system_prompt:
vision_messages = [
{
"role": "system",
"content": [{"type": "text", "text": system_prompt}],
},
user_msg,
]
else:
vision_messages = [user_msg]
try:
input_text = processor.apply_chat_template(
vision_messages, add_generation_prompt = True, tokenize = False
)
except Exception as e:
if system_prompt:
logger.warning(
f"Vision processor for '{self.active_model_name}' may not support "
f"system messages; retrying without. Original error: {e}"
)
vision_messages = [user_msg]
input_text = processor.apply_chat_template(
vision_messages, add_generation_prompt = True, tokenize = False
)
else:
raise
inputs = processor(
image,
input_text,
add_special_tokens = False,
return_tensors = "pt",
).to(model.device)
prompt_text = input_text
else:
# Text-only path for a vision model
formatted_prompt = self.format_chat_prompt(messages, system_prompt)
inputs = raw_tokenizer(formatted_prompt, return_tensors = "pt").to(model.device)
prompt_text = formatted_prompt
# Stream with TextIteratorStreamer + background thread
try:
# Re-emit an open <think> prefill swallowed by skip_prompt (see
# generate_stream).
think_prefix = detect_think_prefill(
prompt_text, getattr(raw_tokenizer, "all_special_tokens", None)
)
import threading
streamer = self._make_text_streamer(
raw_tokenizer,
protocol_source = processor,
# The text-only VLM fallback above did not render with the
# processor template, so its native markers do not describe
# this request's response protocol.
reasoning_channel_markers = detect_reasoning_channel_markers(processor)
if image
else None,
reasoning_channel_markers_resolved = True,
skip_prompt = True,
timeout = 0.2,
cancel_event = cancel_event,
use_harmony = self._is_gpt_oss_model(),
)
generation_kwargs = dict(
**inputs,
streamer = streamer,
max_new_tokens = max_new_tokens,
use_cache = True,
do_sample = temperature > 0,
temperature = temperature,
top_p = top_p,
top_k = top_k,
min_p = min_p,
)
# Presence penalty (GGUF parity) for VLM chat.
_vision_input_ids = inputs.get("input_ids") if hasattr(inputs, "get") else None
if _vision_input_ids is not None:
_pp = _make_presence_penalty_processor(
presence_penalty, int(_vision_input_ids.shape[1])
)
if _pp is not None:
generation_kwargs["logits_processor"] = _pp
stopping_criteria = self._cancel_stopping_criteria(cancel_event)
if stopping_criteria is not None:
generation_kwargs["stopping_criteria"] = stopping_criteria
active_stop_token_ids = self._generation_stop_token_ids(model, generation_kwargs)
err: dict[str, str] = {}
def generate_fn():
with self._generation_lock:
try:
model.generate(**generation_kwargs)
except Exception as e:
err["msg"] = str(e)
if hasattr(streamer, "abort"):
streamer.abort()
logger.error(f"Vision generation error in thread: {e}")
finally:
try:
streamer.end()
except Exception:
pass
thread = threading.Thread(target = generate_fn)
thread.start()
output = think_prefix
# Emit the prefilled <think> before the first token so the block
# renders during prompt prefill (which can take seconds).
if think_prefix:
yield think_prefix
from queue import Empty
import time
generation_complete = False
cancel_deadline = None
try:
while True:
if cancel_event is not None and cancel_event.is_set():
if cancel_deadline is None:
cancel_deadline = time.monotonic() + 10
elif time.monotonic() >= cancel_deadline:
break
try:
new_token = next(streamer)
except StopIteration:
generation_complete = True
break
except Empty:
if not thread.is_alive():
generation_complete = True
output = yield from self._drain_streamer_tail(
streamer, output, active_stop_token_ids
)
break
if cancel_deadline is not None:
remaining = cancel_deadline - time.monotonic()
if remaining <= 0:
break
thread.join(timeout = remaining)
if thread.is_alive():
break
generation_complete = True
output = yield from self._drain_streamer_tail(
streamer, output, active_stop_token_ids
)
break
continue
if new_token:
output, cleaned = self._append_stream_delta(
output, new_token, active_stop_token_ids
)
yield cleaned
finally:
if cancel_event is not None and not generation_complete:
cancel_event.set()
join_timeout = 10
if cancel_deadline is not None:
join_timeout = max(0, cancel_deadline - time.monotonic())
thread.join(timeout = join_timeout)
if thread.is_alive():
logger.warning(
"Vision generation thread did not exit after cancel/join timeout"
)
if err.get("msg"):
raise _GenerationThreadError(err["msg"])
except _GenerationThreadError:
raise
except Exception as e:
logger.error(f"Vision generation error: {e}")
raise
def generate_audio_input_response(
self,
messages,
system_prompt,
audio_array,
temperature,
top_p,
top_k,
min_p,
max_new_tokens,
repetition_penalty,
cancel_event = None,
) -> Generator[str, None, None]:
"""Audio-input (ASR) generation: takes an audio numpy array, streams text.
Uses processor.apply_chat_template with audio embedded in messages (Gemma 3n pattern).
"""
import threading
import numpy as np
model_info = self.models[self.active_model_name]
model = model_info["model"]
processor = model_info.get("processor") or model_info.get("tokenizer")
raw_tokenizer = getattr(processor, "tokenizer", processor)
# Last user text; default matches the notebook prompt
user_text = "Please transcribe this audio."
if messages:
for msg in reversed(messages):
if msg["role"] == "user" and msg.get("content"):
user_text = content_to_text(msg["content"])
break
# ASR-specific default system prompt if none set
if not system_prompt:
system_prompt = "You are an assistant that transcribes speech accurately."
# Gemma 3n format — audio goes INTO apply_chat_template
audio_messages = [
{"role": "system", "content": [{"type": "text", "text": system_prompt}]},
{
"role": "user",
"content": [
{"type": "audio", "audio": audio_array},
{"type": "text", "text": user_text},
],
},
]
# apply_chat_template does audio embedding + tokenization in one step
inputs = processor.apply_chat_template(
audio_messages,
add_generation_prompt = True,
tokenize = True,
return_dict = True,
return_tensors = "pt",
truncation = False,
).to(model.device)
try:
from transformers import TextIteratorStreamer
from queue import Empty
streamer = TextIteratorStreamer(
raw_tokenizer,
skip_prompt = True,
skip_special_tokens = True,
timeout = 0.2,
)
# Notebook uses do_sample=False (greedy) for ASR accuracy
generation_kwargs = dict(
**inputs,
streamer = streamer,
max_new_tokens = max_new_tokens,
use_cache = True,
do_sample = False,
)
err: dict[str, str] = {}
def generate_fn():
with self._generation_lock:
try:
model.generate(**generation_kwargs)
except Exception as e:
err["msg"] = str(e)
logger.error(f"Audio input generation error in thread: {e}")
finally:
try:
streamer.end()
except Exception:
pass
thread = threading.Thread(target = generate_fn)
thread.start()
output = ""
try:
while True:
if cancel_event is not None and cancel_event.is_set():
break
try:
new_token = next(streamer)
except StopIteration:
break
except Empty:
if not thread.is_alive():
break
continue
if new_token:
output += new_token
yield new_token
finally:
if cancel_event is not None:
cancel_event.set()
thread.join(timeout = 10)
if thread.is_alive():
logger.warning(
"Audio input generation thread did not exit after cancel/join timeout"
)
if err.get("msg"):
raise _GenerationThreadError(err["msg"])
except _GenerationThreadError:
raise
except Exception as e:
logger.error(f"Audio input generation error: {e}")
raise
def generate_whisper_response(
self,
audio_array,
cancel_event = None,
) -> Generator[str, None, None]:
"""Whisper ASR: takes an audio numpy array, yields transcribed text.
Uses the pre-built transformers pipeline created at model load.
"""
model_info = self.models[self.active_model_name]
whisper_pipe = model_info.get("whisper_pipeline")
if not whisper_pipe:
yield "Error: Whisper pipeline not initialized"
return
try:
with self._generation_lock:
result = whisper_pipe({"raw": audio_array, "sampling_rate": 16000})
text = result.get("text", "") if isinstance(result, dict) else str(result)
if text:
yield text
except Exception as e:
logger.error(f"Whisper ASR error: {e}")
yield f"Error: {str(e)}"
def _is_gpt_oss_model(self, model_name: str = None) -> bool:
"""Whether the given (or active) model uses the gpt-oss harmony protocol."""
from utils.datasets import is_gpt_oss_model_name
return is_gpt_oss_model_name(model_name or self.active_model_name or "")
def _make_text_streamer(
self,
tokenizer,
*,
protocol_source = None,
reasoning_channel_markers = None,
reasoning_channel_markers_resolved: bool = False,
skip_prompt: bool = True,
timeout: float = 0.2,
cancel_event = None,
use_harmony: bool = False,
):
"""Create the streamer matching this model's native response protocol."""
if use_harmony:
try:
return HarmonyTextStreamer(
tokenizer,
skip_prompt = skip_prompt,
timeout = timeout,
)
except Exception as e:
logger.warning(f"HarmonyTextStreamer init failed, falling back: {e}")
return TextIteratorStreamer(
tokenizer,
skip_prompt = skip_prompt,
skip_special_tokens = True,
timeout = timeout,
)
markers = (
reasoning_channel_markers
if reasoning_channel_markers_resolved
else reasoning_channel_markers
or detect_reasoning_channel_markers(protocol_source or tokenizer)
)
if markers is not None:
return ReasoningTextIteratorStreamer(
tokenizer,
markers = markers,
skip_prompt = skip_prompt,
timeout = timeout,
cancel_event = cancel_event,
)
return TextIteratorStreamer(
tokenizer,
skip_prompt = skip_prompt,
skip_special_tokens = True,
timeout = timeout,
)
def _append_stream_delta(
self,
output: str,
new_token: str,
stop_token_ids = None,
):
"""Append a streamer delta and apply response-boundary cleanup."""
output += new_token
return output, self._clean_generated_text(output, stop_token_ids = stop_token_ids)
def _drain_streamer_tail(
self,
streamer,
output: str,
stop_token_ids = None,
):
"""Drain queued streamer text after the producer exits."""
while True:
try:
new_token = next(streamer)
except StopIteration:
return output
except Exception:
return output
if new_token:
output, cleaned = self._append_stream_delta(
output, new_token, stop_token_ids = stop_token_ids
)
yield cleaned
def generate_stream(
self,
prompt: str,
temperature: float = 0.7,
top_p: float = 0.9,
top_k: int = 40,
min_p: float = 0.0,
max_new_tokens: int = 256,
repetition_penalty: float = 1.0,
cancel_event = None,
_adapter_state = None,
presence_penalty: float = 0.0,
reasoning_channel_markers = None,
reasoning_channel_markers_resolved: bool = False,
) -> Generator[str, None, None]:
"""Generate a streaming text response (text models only).
_adapter_state: if not None, the background thread toggles adapters
before model.generate(), under _generation_lock.
``presence_penalty`` matches the GGUF sampling path via a logits processor (0 disables it).
"""
if not self.active_model_name:
raise RuntimeError("No active model")
model_info = self.models[self.active_model_name]
model = model_info["model"]
# For VLMs the stored "tokenizer" is actually the processor. Unwrap to
# the real tokenizer so TextIteratorStreamer's skip_prompt /
# skip_special_tokens work correctly.
tokenizer = model_info["tokenizer"]
tokenizer = getattr(tokenizer, "tokenizer", tokenizer)
try:
inputs = tokenizer(prompt, return_tensors = "pt").to(model.device)
import threading
# skip_prompt swallows an open <think> prefilled by the template;
# re-emit it so the frontend can render the thinking block.
# gpt-oss emits its own tags via HarmonyTextStreamer.
think_prefix = (
""
if self._is_gpt_oss_model()
else detect_think_prefill(prompt, getattr(tokenizer, "all_special_tokens", None))
)
streamer = self._make_text_streamer(
tokenizer,
protocol_source = model_info.get("tokenizer"),
reasoning_channel_markers = reasoning_channel_markers,
reasoning_channel_markers_resolved = reasoning_channel_markers_resolved,
skip_prompt = True,
timeout = 0.2,
cancel_event = cancel_event,
use_harmony = self._is_gpt_oss_model(),
)
generation_kwargs = dict(
**inputs,
streamer = streamer,
max_new_tokens = max_new_tokens,
temperature = temperature,
top_p = top_p,
top_k = top_k,
min_p = min_p,
repetition_penalty = repetition_penalty,
do_sample = temperature > 0,
# Resolved once at load (chat_template-derived turn-end tokens).
eos_token_id = model_info.get("chat_turn_end_eos_ids") or tokenizer.eos_token_id,
pad_token_id = tokenizer.eos_token_id
if tokenizer.pad_token_id is None
else tokenizer.pad_token_id,
)
active_stop_token_ids = self._generation_stop_token_ids(model, generation_kwargs)
# Presence penalty (GGUF parity); prompt_len excludes prompt tokens.
_pp = _make_presence_penalty_processor(
presence_penalty, int(inputs["input_ids"].shape[1])
)
if _pp is not None:
generation_kwargs["logits_processor"] = _pp
stopping_criteria = self._cancel_stopping_criteria(cancel_event)
if stopping_criteria is not None:
generation_kwargs["stopping_criteria"] = stopping_criteria
def generate_fn():
with self._generation_lock:
try:
if _adapter_state is not None:
self._apply_adapter_state(_adapter_state)
model.generate(**generation_kwargs)
except Exception as e:
err["msg"] = str(e)
if hasattr(streamer, "abort"):
streamer.abort()
logger.error(f"Generation error: {e}")
finally:
try:
streamer.end()
except Exception:
pass
err: dict[str, str] = {}
thread = threading.Thread(target = generate_fn)
thread.start()
output = think_prefix
# Emit the prefilled <think> before the first token so the block
# renders during prompt prefill (which can take seconds).
if think_prefix:
yield think_prefix
from queue import Empty
import time
generation_complete = False
cancel_deadline = None
try:
while True:
if cancel_event is not None and cancel_event.is_set():
if cancel_deadline is None:
cancel_deadline = time.monotonic() + 10
elif time.monotonic() >= cancel_deadline:
break
try:
new_token = next(streamer)
except StopIteration:
generation_complete = True
break
except Empty:
if not thread.is_alive():
generation_complete = True
output = yield from self._drain_streamer_tail(
streamer, output, active_stop_token_ids
)
break
if cancel_deadline is not None:
remaining = cancel_deadline - time.monotonic()
if remaining <= 0:
break
thread.join(timeout = remaining)
if thread.is_alive():
break
generation_complete = True
output = yield from self._drain_streamer_tail(
streamer, output, active_stop_token_ids
)
break
continue
if new_token:
output, cleaned = self._append_stream_delta(
output, new_token, active_stop_token_ids
)
yield cleaned
finally:
# Set cancel_event only on early exit (user cancel), NOT on
# normal completion. It's a shared mp.Event; setting it
# unconditionally would leave a stale cancel signal that could
# disrupt the next serialized request (e.g. compare mode).
if cancel_event is not None and not generation_complete:
cancel_event.set()
join_timeout = 10
if cancel_deadline is not None:
join_timeout = max(0, cancel_deadline - time.monotonic())
thread.join(timeout = join_timeout)
if thread.is_alive():
logger.warning("Generation thread did not exit after cancel/join timeout")
if err.get("msg"):
raise _GenerationThreadError(err["msg"])
except _GenerationThreadError:
raise
except Exception as e:
logger.error(f"Error during generation: {e}")
raise
# ── Audio (TTS) Generation ────────────────────────────────────
def generate_audio_response(
self,
text: str,
temperature: float = 0.6,
top_p: float = 0.95,
top_k: int = 50,
min_p: float = 0.0,
max_new_tokens: int = 2048,
repetition_penalty: float = 1.0,
use_adapter: Optional[Union[bool, str]] = None,
) -> Tuple[bytes, int]:
"""Generate audio from text for TTS models.
Returns (wav_bytes, sample_rate). Blocking — full audio before return.
"""
if not self.active_model_name:
raise RuntimeError("No active model")
model_info = self.models[self.active_model_name]
audio_type = model_info.get("audio_type")
model = model_info["model"]
tokenizer = model_info.get("tokenizer")
if not audio_type:
raise RuntimeError(f"Model {self.active_model_name} is not an audio model")
top_k = self._normalize_top_k(top_k)
with self._generation_lock:
if use_adapter is not None:
self._apply_adapter_state(use_adapter)
if audio_type == "snac":
return self._generate_snac(
model,
tokenizer,
text,
temperature,
top_p,
max_new_tokens,
repetition_penalty,
)
elif audio_type == "csm":
processor = model_info.get("processor", tokenizer)
return self._generate_csm(model, processor, text, max_new_tokens)
elif audio_type == "bicodec":
return self._generate_bicodec(
model, tokenizer, text, temperature, top_k, max_new_tokens
)
elif audio_type == "dac":
return self._generate_dac(
model,
tokenizer,
text,
temperature,
top_k,
top_p,
min_p,
max_new_tokens,
repetition_penalty,
)
else:
raise RuntimeError(f"Unknown audio_type: {audio_type}")
def _generate_snac(
self, model, tokenizer, text, temperature, top_p, max_new_tokens, repetition_penalty
):
"""Generate audio using SNAC codec (Orpheus)."""
device = model.device
start_token = torch.tensor([[128259]], device = device) # START_OF_HUMAN
end_tokens = torch.tensor([[128009, 128260]], device = device) # EOT, END_OF_HUMAN
text_ids = tokenizer(text, return_tensors = "pt").input_ids.to(device)
input_ids = torch.cat([start_token, text_ids, end_tokens], dim = 1)
attention_mask = torch.ones_like(input_ids)
generated = model.generate(
input_ids = input_ids,
attention_mask = attention_mask,
max_new_tokens = max_new_tokens,
do_sample = True,
temperature = temperature,
top_p = top_p,
repetition_penalty = repetition_penalty,
eos_token_id = 128258, # END_OF_SPEECH
use_cache = True,
)
return self._audio_codec_manager.decode_snac(generated, str(device))
def _generate_csm(self, model, processor, text, max_new_tokens):
"""Generate audio using CSM (Sesame)."""
speaker_id = 0
inputs = processor(
f"[{speaker_id}]{text}", add_special_tokens = True, return_tensors = "pt"
).to(model.device)
audio_values = model.generate(**inputs, max_new_tokens = max_new_tokens, output_audio = True)
return self._audio_codec_manager.decode_csm(audio_values)
def _generate_bicodec(self, model, tokenizer, text, temperature, top_k, max_new_tokens):
"""Generate audio using BiCodec (Spark-TTS)."""
prompt = "<|task_tts|><|start_content|>" + text + "<|end_content|><|start_global_token|>"
inputs = tokenizer([prompt], return_tensors = "pt").to(model.device)
generated = model.generate(
**inputs,
max_new_tokens = max_new_tokens,
do_sample = True,
temperature = temperature,
top_k = top_k,
eos_token_id = tokenizer.eos_token_id,
pad_token_id = tokenizer.pad_token_id,
)
new_tokens = generated[:, inputs.input_ids.shape[1] :]
decoded_text = tokenizer.batch_decode(new_tokens, skip_special_tokens = False)[0]
return self._audio_codec_manager.decode_bicodec(decoded_text, str(model.device))
def _generate_dac(
self,
model,
tokenizer,
text,
temperature,
top_k,
top_p,
min_p,
max_new_tokens,
repetition_penalty,
):
"""Generate audio using DAC (OuteTTS). Follows Oute_TTS_(1B).ipynb exactly."""
# Monkey-patch RepetitionPenaltyLogitsProcessor with a 64-token window
# (same as the OuteTTS notebook) to avoid degenerate repetition.
self._patch_repetition_penalty_processor()
prompt = (
"<|im_start|>\n<|text_start|>"
+ text
+ "<|text_end|>\n<|audio_start|><|global_features_start|>\n"
)
with torch.inference_mode():
# Derive the autocast device from the loaded model, not from the
# global backend: a CPU-fallback DAC on an XPU/CUDA host must not
# open a GPU autocast context around CPU tensors.
device_type = (
model.device.type
if hasattr(model.device, "type")
else str(model.device).split(":", 1)[0]
)
# Clamp to autocast-supported backends so exotic devices
# (e.g. "meta" during accelerate offloaded loading) do not raise.
# MPS is autocast-supported since torch 2.3, keep it in the set.
if device_type not in ("cuda", "xpu", "mps", "cpu"):
device_type = "cpu"
# CPU and XPU autocast only accept bfloat16/float16. For a
# float32 model, skip autocast entirely to avoid raising or
# producing a warning on every generate call.
autocast_dtype_supported = model.dtype in (torch.bfloat16, torch.float16)
if device_type in ("cpu", "xpu") and not autocast_dtype_supported:
autocast_ctx = contextlib.nullcontext()
else:
autocast_ctx = torch.amp.autocast(device_type, dtype = model.dtype)
with autocast_ctx:
inputs = tokenizer([prompt], return_tensors = "pt").to(model.device)
generated = model.generate(
**inputs,
temperature = temperature,
top_k = top_k,
top_p = top_p,
min_p = min_p,
repetition_penalty = repetition_penalty,
max_new_tokens = max_new_tokens,
)
decoded_text = tokenizer.batch_decode(generated, skip_special_tokens = False)[0]
return self._audio_codec_manager.decode_dac(decoded_text, str(model.device))
_repetition_penalty_patched = False
@classmethod
def _patch_repetition_penalty_processor(cls):
"""Monkey-patch transformers' RepetitionPenaltyLogitsProcessor with a
64-token sliding-window variant (from the OuteTTS notebook).
Applied once per process.
"""
if cls._repetition_penalty_patched:
return
cls._repetition_penalty_patched = True
from transformers import LogitsProcessor
import transformers.generation.utils as generation_utils
class RepetitionPenaltyLogitsProcessorPatch(LogitsProcessor):
def __init__(self, penalty: float):
self.penalty_last_n = 64
if not isinstance(penalty, float) or penalty <= 0:
raise ValueError(f"`penalty` has to be a positive float, but is {penalty}")
self.penalty = penalty
@torch.no_grad()
def __call__(
self, input_ids: torch.LongTensor, scores: torch.FloatTensor
) -> torch.FloatTensor:
if self.penalty_last_n == 0 or self.penalty == 1.0:
return scores
batch_size, seq_len = input_ids.shape
vocab_size = scores.shape[-1]
for b in range(batch_size):
start_index = max(0, seq_len - self.penalty_last_n)
window_indices = input_ids[b, start_index:]
if window_indices.numel() == 0:
continue
for token_id in set(window_indices.tolist()):
if token_id >= vocab_size:
continue
logit = scores[b, token_id]
scores[b, token_id] = (
logit * self.penalty if logit <= 0 else logit / self.penalty
)
return scores
generation_utils.RepetitionPenaltyLogitsProcessor = RepetitionPenaltyLogitsProcessorPatch
logger.info("Patched RepetitionPenaltyLogitsProcessor with 64-token window for OuteTTS")
def _apply_chat_template_for_generation(
self,
tokenizer,
messages: list,
*,
tools: Optional[list] = None,
enable_thinking: Optional[bool] = None,
reasoning_effort: Optional[str] = None,
preserve_thinking: Optional[bool] = None,
) -> str:
"""Render the chat prompt, peeling kwargs the template doesn't
understand. Delegates to the dependency-light helper module so the
fallback chain is unit-testable without pulling unsloth / torch into
the test sandbox.
"""
from core.inference.chat_template_helpers import (
apply_chat_template_for_generation,
)
return apply_chat_template_for_generation(
tokenizer,
messages,
tools = tools,
enable_thinking = enable_thinking,
reasoning_effort = reasoning_effort,
preserve_thinking = preserve_thinking,
)
def format_chat_prompt(
self,
messages: list,
system_prompt: str = None,
) -> str:
if not self.active_model_name or self.active_model_name not in self.models:
logger.error("No active model available")
return ""
if self.models[self.active_model_name].get("tokenizer") is None:
logger.error("Tokenizer not loaded for active model")
return ""
chat_template_info = self.models[self.active_model_name].get("chat_template_info", {})
tokenizer = self.models[self.active_model_name]["tokenizer"]
tokenizer = getattr(tokenizer, "tokenizer", tokenizer)
chat_messages = []
if system_prompt:
chat_messages.append({"role": "system", "content": system_prompt})
last_role = "system" if system_prompt else None
for msg in messages:
role = msg.get("role", "")
content = content_to_text(msg.get("content", ""))
if role in ["system", "user", "assistant"] and content.strip():
if role == last_role:
logger.debug(f"Skipping consecutive {role} message to maintain alternation")
continue
if role == "user":
import re
clean_content = re.sub(r"<[^>]+>", "", content).strip()
if clean_content:
chat_messages.append({"role": role, "content": clean_content})
last_role = role
elif role == "assistant" and content.strip():
chat_messages.append({"role": role, "content": content})
last_role = role
elif role == "system":
continue
if chat_messages and chat_messages[-1]["role"] == "assistant":
logger.debug("Removing final assistant message to ensure proper alternation")
chat_messages.pop()
logger.info(f"Sending {len(chat_messages)} messages to tokenizer:")
for i, msg in enumerate(chat_messages):
logger.info(f" {i}: {msg['role']} - {msg['content'][:50]}...")
try:
formatted_prompt = tokenizer.apply_chat_template(
chat_messages, tokenize = False, add_generation_prompt = True
)
logger.info(f"Successfully applied tokenizer's native chat template")
return formatted_prompt
except Exception as e:
error_msg = str(e).lower()
if "chat_template is not set" in error_msg or "no template argument" in error_msg:
logger.info(
f"Base model detected - no built-in chat template available, using fallback formatting"
)
else:
logger.warning(f"Failed to apply tokenizer chat template: {e}")
logger.debug(
f"""Failed with messages: {[f"{m['role']}: {m['content'][:30]}..." for m in chat_messages]}"""
)
if chat_template_info.get("has_template", False):
logger.info("Falling back to manual template formatting based on detected patterns")
template_type = chat_template_info.get("format_type", "generic")
manual_prompt = self._format_chat_manual(
chat_messages,
template_type,
chat_template_info.get("special_tokens", {}),
)
logger.info(f"Manual template result: {manual_prompt[:200]}...")
return manual_prompt
else:
logger.info("Using generic chat formatting for base model")
return self._format_generic_template(chat_messages, {})
def _format_chat_manual(self, messages: list, template_type: str, special_tokens: dict) -> str:
"""Manual chat-formatting fallback when the tokenizer template fails.
Args:
messages: List of message dictionaries
template_type: Detected template type
special_tokens: Dictionary of special tokens
Returns:
str: Manually formatted prompt
"""
if template_type == "llama3":
return self._format_llama3_template(messages, special_tokens)
elif template_type == "mistral":
return self._format_mistral_template(messages, special_tokens)
elif template_type == "chatml":
return self._format_chatml_template(messages, special_tokens)
elif template_type == "alpaca":
return self._format_alpaca_template(messages, special_tokens)
else:
return self._format_generic_template(messages, special_tokens)
def _format_llama3_template(self, messages: list, special_tokens: dict) -> str:
"""Format messages using Llama 3 template"""
bos_token = special_tokens.get("bos_token", "<|begin_of_text|>")
formatted = bos_token
for msg in messages:
role = msg["role"]
content = content_to_text(msg["content"])
formatted += f"<|start_header_id|>{role}<|end_header_id|>\n\n{content}<|eot_id|>"
formatted += "<|start_header_id|>assistant<|end_header_id|>\n\n"
return formatted
def _format_mistral_template(self, messages: list, special_tokens: dict) -> str:
"""Format messages using Mistral template"""
bos_token = special_tokens.get("bos_token", "<s>")
formatted = bos_token
system_msg = None
conversation = []
for msg in messages:
if msg["role"] == "system":
system_msg = content_to_text(msg["content"])
else:
conversation.append(msg)
i = 0
while i < len(conversation):
if conversation[i]["role"] == "user":
user_content = content_to_text(conversation[i]["content"])
if system_msg and i == 0:
user_content = f"{system_msg}\n\n{user_content}"
formatted += f"[INST] {user_content} [/INST]"
if i + 1 < len(conversation) and conversation[i + 1]["role"] == "assistant":
formatted += f" {content_to_text(conversation[i + 1]['content'])}</s>"
i += 2
else:
formatted += " "
break
else:
i += 1
return formatted
def _format_chatml_template(self, messages: list, special_tokens: dict) -> str:
"""Format messages using ChatML template"""
formatted = ""
for msg in messages:
role = msg["role"]
content = content_to_text(msg["content"])
formatted += f"<|im_start|>{role}\n{content}<|im_end|>\n"
formatted += "<|im_start|>assistant\n"
return formatted
def _format_alpaca_template(self, messages: list, special_tokens: dict) -> str:
"""Format messages using Alpaca template"""
formatted = ""
system_msg = None
for msg in messages:
content = content_to_text(msg["content"])
if msg["role"] == "system":
system_msg = content
elif msg["role"] == "user":
if system_msg:
formatted += f"### Instruction:\n{system_msg}\n\n### Input:\n{content}\n\n### Response:\n"
system_msg = None
else:
formatted += f"### Human:\n{content}\n\n### Assistant:\n"
elif msg["role"] == "assistant":
formatted += f"{content}\n\n"
return formatted
def _format_generic_template(self, messages: list, special_tokens: dict) -> str:
"""Generic fallback formatting"""
formatted = ""
for msg in messages:
role = msg["role"].title()
content = content_to_text(msg["content"])
formatted += f"{role}: {content}\n"
formatted += "Assistant: "
return formatted
def check_vision_model_compatibility(self) -> bool:
"""Whether the current model supports vision."""
current_model = self.get_current_model()
if current_model and current_model in self.models:
return self.models[current_model].get("is_vision", False)
return False
def _reset_model_generation_state(self, model_name: str):
"""Reset generation state for a specific model to prevent contamination."""
if model_name not in self.models:
return
model = self.models[model_name].get("model")
if not model:
return
try:
# Common pattern for Unsloth/Hugging Face models
if hasattr(model, "past_key_values"):
model.past_key_values = None
if hasattr(model, "generation_config"):
if hasattr(model.generation_config, "past_key_values"):
model.generation_config.past_key_values = None
logger.debug(f"Reset generation state for model: {model_name}")
except Exception as e:
logger.warning(f"Could not fully reset model state for {model_name}: {e}")
def reset_generation_state(self, caller_cancel_event = None):
"""Reset any cached generation state to prevent hanging after errors
``caller_cancel_event`` is accepted for signature parity with the
orchestrator, which uses it to drop a reset from a request that never
started. Nothing here cancels a live generation, so it is unused.
"""
try:
# Clear cached state for ALL loaded models
for model_name in self.models.keys():
self._reset_model_generation_state(model_name)
clear_gpu_cache()
logger.debug("Cleared GPU cache")
import gc
gc.collect()
logger.info("Performed comprehensive generation state reset")
except Exception as e:
logger.warning(f"Could not fully reset generation state: {e}")
def resize_image(
self,
img,
max_size: int = 800,
):
"""Resize image while maintaining aspect ratio if either dimension exceeds max_size"""
if img is None:
return None
if img.size[0] > max_size or img.size[1] > max_size:
from PIL import Image
ratio = min(max_size / img.size[0], max_size / img.size[1])
new_size = (int(img.size[0] * ratio), int(img.size[1] * ratio))
return img.resize(new_size, Image.Resampling.LANCZOS)
return img
def _generation_stop_token_ids(self, model, generation_kwargs: dict):
"""Return the stop-token ids active for a ``generate`` call."""
if "eos_token_id" in generation_kwargs:
return generation_kwargs.get("eos_token_id")
generation_config = getattr(model, "generation_config", None)
eos_token_id = getattr(generation_config, "eos_token_id", None)
if eos_token_id is not None:
return eos_token_id
config = getattr(model, "config", None)
return getattr(config, "eos_token_id", None)
def _cancel_stopping_criteria(self, cancel_event):
"""Build a Transformers stopping criteria list for user cancellation."""
if cancel_event is None:
return None
from transformers.generation.stopping_criteria import (
StoppingCriteria,
StoppingCriteriaList,
)
class _CancelCriteria(StoppingCriteria):
def __init__(self, ev):
self.ev = ev
def __call__(self, input_ids, scores, **kwargs):
return self.ev.is_set()
return StoppingCriteriaList([_CancelCriteria(cancel_event)])
def _clean_generated_text(
self,
text: str,
*,
stop_token_ids = None,
) -> str:
"""Strip leaked response-boundary tokens after streaming."""
if self._is_gpt_oss_model():
# HarmonyTextStreamer emits clean <think>...</think>. Strip any
# harmony protocol tokens and other gpt-oss tokens (e.g.
# <|return|>) that leak past the streamer.
import re
text = re.sub(r"<\|[a-z_]+\|>", "", text)
return text.strip()
tokenizer = self.models.get(self.active_model_name, {}).get("tokenizer")
tokenizer = getattr(tokenizer, "tokenizer", tokenizer)
if tokenizer:
if stop_token_ids is None:
stop_token_ids = self.models.get(self.active_model_name, {}).get(
"chat_turn_end_eos_ids"
)
if isinstance(stop_token_ids, int):
stop_token_ids = (stop_token_ids,)
for token_id in stop_token_ids or ():
try:
token = tokenizer.convert_ids_to_tokens(int(token_id))
except Exception:
token = None
if isinstance(token, str) and token and text.endswith(token):
text = text[: -len(token)]
elif (
isinstance(token, str)
and token
and text.endswith("</think>")
and text[: -len("</think>")].endswith(token)
):
text = text[: -len("</think>") - len(token)] + "</think>"
return text.strip()
def _load_chat_template_info(self, model_name: str):
if model_name not in self.models or not self.models[model_name].get("tokenizer"):
return
tokenizer = self.models[model_name]["tokenizer"]
chat_template_info = {
"has_template": False,
"template": None,
"format_type": "generic",
"special_tokens": {},
"template_name": None,
}
try:
from utils.datasets import MODEL_TO_TEMPLATE_MAPPER
# Exact match first
model_name_lower = model_name.lower()
if model_name_lower in MODEL_TO_TEMPLATE_MAPPER:
chat_template_info["template_name"] = MODEL_TO_TEMPLATE_MAPPER[model_name_lower]
logger.info(
f"Detected template '{chat_template_info['template_name']}' for {model_name} from mapper"
)
else:
# Partial match (for variants like model_name-bnb-4bit)
for key in MODEL_TO_TEMPLATE_MAPPER:
if key in model_name_lower or model_name_lower in key:
chat_template_info["template_name"] = MODEL_TO_TEMPLATE_MAPPER[key]
logger.info(
f"Detected template '{chat_template_info['template_name']}' for {model_name} (partial match)"
)
break
except Exception as e:
logger.warning(f"Could not detect template from mapper for {model_name}: {e}")
try:
if hasattr(tokenizer, "chat_template") and tokenizer.chat_template:
chat_template_info["has_template"] = True
chat_template_info["template"] = tokenizer.chat_template
template_str = tokenizer.chat_template.lower()
if "start_header_id" in template_str and "end_header_id" in template_str:
chat_template_info["format_type"] = "llama3"
elif "[inst]" in template_str and "[/inst]" in template_str:
chat_template_info["format_type"] = "mistral"
elif "<|im_start|>" in template_str and "<|im_end|>" in template_str:
chat_template_info["format_type"] = "chatml"
elif "### instruction:" in template_str or "### human:" in template_str:
chat_template_info["format_type"] = "alpaca"
else:
chat_template_info["format_type"] = "custom"
logger.info(
f"Loaded chat template for {model_name} (detected as {chat_template_info['format_type']} format)"
)
logger.debug(f"Template preview: {tokenizer.chat_template[:200]}...")
special_tokens = {}
if hasattr(tokenizer, "bos_token") and tokenizer.bos_token:
special_tokens["bos_token"] = tokenizer.bos_token
if hasattr(tokenizer, "eos_token") and tokenizer.eos_token:
special_tokens["eos_token"] = tokenizer.eos_token
if hasattr(tokenizer, "pad_token") and tokenizer.pad_token:
special_tokens["pad_token"] = tokenizer.pad_token
chat_template_info["special_tokens"] = special_tokens
else:
logger.info(f"No chat template found for {model_name}, will use generic formatting")
except Exception as e:
logger.error(f"Error loading chat template info for {model_name}: {e}")
self.models[model_name]["chat_template_info"] = chat_template_info
if chat_template_info["has_template"]:
logger.info(
f"Chat template loaded for {model_name}: {chat_template_info['format_type']} format"
)
else:
logger.info(f"No built-in chat template for {model_name}, will use generic formatting")
def get_current_model(self) -> Optional[str]:
"""Currently active model name."""
return self.active_model_name
def is_model_loading(self) -> bool:
"""Whether any model is currently loading."""
return len(self.loading_models) > 0
def get_loading_model(self) -> Optional[str]:
"""Name of the currently loading model."""
return next(iter(self.loading_models)) if self.loading_models else None
def load_model_simple(
self,
model_path: str,
hf_token: Optional[str] = None,
max_seq_length: int = 2048,
load_in_4bit: bool = True,
) -> bool:
"""Simple model-loading wrapper for the chat interface. Takes a string
path and builds the ModelConfig internally.
Args:
model_path: Model name or path (e.g., "unsloth/llama-3-8b")
hf_token: HuggingFace token for gated models
max_seq_length: Maximum sequence length
load_in_4bit: Whether to use 4-bit quantization
Returns:
bool: True if successful, False otherwise
"""
try:
config = ModelConfig.from_ui_selection(
model_path,
lora_path = None, # No LoRA for chat
is_lora = False,
)
return self.load_model(
config = config,
max_seq_length = max_seq_length,
dtype = None, # Auto-detect
load_in_4bit = load_in_4bit,
hf_token = hf_token,
)
except Exception as e:
logger.error(f"Error in load_model_simple: {e}")
return False
# Global inference backend instance
inference_backend = InferenceBackend()
def get_inference_backend() -> InferenceBackend:
return inference_backend