unsloth/studio/backend/models/inference.py
Shine1i 0db7da96cc feat: support disabling top-k sampling with -1 and standardize normalization logic
- Updated top-k parameter range to accept -1 in models and frontend.
- Added utility to normalize top-k for backend compatibility.
2026-02-16 21:33:24 +01:00

202 lines
8 KiB
Python

"""
Pydantic schemas for Inference API
"""
from __future__ import annotations
import time
import uuid
from typing import Annotated, Literal, Optional, List, Union
from pydantic import BaseModel, Discriminator, Field, Tag
class LoadRequest(BaseModel):
"""Request to load a model for inference"""
model_path: str = Field(..., description="Model identifier or local path")
hf_token: Optional[str] = Field(None, description="HuggingFace token for gated models")
max_seq_length: int = Field(2048, ge=128, le=32768, description="Maximum sequence length")
load_in_4bit: bool = Field(True, description="Load model in 4-bit quantization")
is_lora: bool = Field(False, description="Whether this is a LoRA adapter")
class UnloadRequest(BaseModel):
"""Request to unload a model"""
model_path: str = Field(..., description="Model identifier to unload")
class GenerateRequest(BaseModel):
"""Request for text generation (legacy /generate/stream endpoint)"""
messages: List[dict] = Field(..., description="Chat messages in OpenAI format")
system_prompt: str = Field("You are a helpful AI assistant.", description="System prompt")
temperature: float = Field(0.7, ge=0.0, le=2.0, description="Sampling temperature")
top_p: float = Field(0.9, ge=0.0, le=1.0, description="Top-p sampling")
top_k: int = Field(40, ge=-1, le=100, description="Top-k sampling")
max_new_tokens: int = Field(512, ge=1, le=4096, description="Maximum tokens to generate")
repetition_penalty: float = Field(1.1, ge=1.0, le=2.0, description="Repetition penalty")
image_base64: Optional[str] = Field(None, description="Base64 encoded image for vision models")
class LoadResponse(BaseModel):
"""Response after loading a model"""
status: str = Field(..., description="Load status")
model: str = Field(..., description="Model identifier")
display_name: str = Field(..., description="Display name of the model")
is_vision: bool = Field(False, description="Whether model is a vision model")
is_lora: bool = Field(False, description="Whether model is a LoRA adapter")
inference: dict = Field(..., description="Inference parameters (temperature, top_p, top_k, min_p)")
class UnloadResponse(BaseModel):
"""Response after unloading a model"""
status: str = Field(..., description="Unload status")
model: str = Field(..., description="Model identifier that was unloaded")
class InferenceStatusResponse(BaseModel):
"""Current inference backend status"""
active_model: Optional[str] = Field(None, description="Currently active model identifier")
is_vision: bool = Field(False, description="Whether the active model is a vision model")
loading: List[str] = Field(default_factory=list, description="Models currently being loaded")
loaded: List[str] = Field(default_factory=list, description="Models currently loaded")
# =====================================================================
# OpenAI-Compatible Chat Completions Models
# =====================================================================
# ── Multimodal content parts (OpenAI vision format) ──────────────
class TextContentPart(BaseModel):
"""Text content part in a multimodal message."""
type: Literal["text"]
text: str
class ImageUrl(BaseModel):
"""Image URL object — supports data URIs and remote URLs."""
url: str = Field(..., description="data:image/png;base64,... or https://...")
detail: Optional[Literal["auto", "low", "high"]] = "auto"
class ImageContentPart(BaseModel):
"""Image content part in a multimodal message."""
type: Literal["image_url"]
image_url: ImageUrl
def _content_part_discriminator(v):
if isinstance(v, dict):
return v.get("type")
return getattr(v, "type", None)
ContentPart = Annotated[
Union[
Annotated[TextContentPart, Tag("text")],
Annotated[ImageContentPart, Tag("image_url")],
],
Discriminator(_content_part_discriminator),
]
"""Union type for multimodal content parts, discriminated by the 'type' field."""
# ── Messages ─────────────────────────────────────────────────────
class ChatMessage(BaseModel):
"""
A single message in the conversation.
``content`` may be a plain string (text-only) or a list of
content parts for multimodal messages (OpenAI vision format).
"""
role: Literal["system", "user", "assistant"] = Field(..., description="Message role")
content: Union[str, list[ContentPart]] = Field(..., description="Message content (string or multimodal parts)")
class ChatCompletionRequest(BaseModel):
"""
OpenAI-compatible chat completion request.
Extensions (non-OpenAI fields) are marked with 'x-unsloth'.
"""
model: str = Field("default", description="Model identifier (informational; the active model is used)")
messages: list[ChatMessage] = Field(..., description="Conversation messages")
stream: bool = Field(True, description="Whether to stream the response via SSE")
temperature: float = Field(0.7, ge=0.0, le=2.0)
top_p: float = Field(0.9, ge=0.0, le=1.0)
max_tokens: Optional[int] = Field(512, ge=1, le=4096, description="Maximum tokens to generate")
# ── Unsloth extensions (ignored by standard OpenAI clients) ──
top_k: int = Field(40, ge=-1, le=100, description="[x-unsloth] Top-k sampling")
min_p: float = Field(0.0, ge=0.0, le=1.0, description="[x-unsloth] Min-p sampling threshold")
repetition_penalty: float = Field(1.1, ge=1.0, le=2.0, description="[x-unsloth] Repetition penalty")
image_base64: Optional[str] = Field(None, description="[x-unsloth] Base64-encoded image for vision models")
use_adapter: Optional[Union[bool, str]] = Field(
None,
description=(
"[x-unsloth] Adapter control for compare mode. "
"null = no change (default), "
"false = disable adapters (base model), "
"true = enable the current adapter, "
"string = enable a specific adapter by name."
),
)
# ── Streaming response chunks ────────────────────────────────────
class ChoiceDelta(BaseModel):
"""Delta content for a streaming chunk."""
role: Optional[str] = None
content: Optional[str] = None
class ChunkChoice(BaseModel):
"""A single choice in a streaming chunk."""
index: int = 0
delta: ChoiceDelta
finish_reason: Optional[Literal["stop", "length"]] = None
class ChatCompletionChunk(BaseModel):
"""A single SSE chunk in OpenAI streaming format."""
id: str = Field(default_factory=lambda: f"chatcmpl-{uuid.uuid4().hex[:12]}")
object: Literal["chat.completion.chunk"] = "chat.completion.chunk"
created: int = Field(default_factory=lambda: int(time.time()))
model: str = "default"
choices: list[ChunkChoice]
# ── Non-streaming response ───────────────────────────────────────
class CompletionMessage(BaseModel):
"""The assistant's complete response message."""
role: Literal["assistant"] = "assistant"
content: str
class CompletionChoice(BaseModel):
"""A single choice in a non-streaming response."""
index: int = 0
message: CompletionMessage
finish_reason: Literal["stop", "length"] = "stop"
class CompletionUsage(BaseModel):
"""Token usage statistics (approximate)."""
prompt_tokens: int = 0
completion_tokens: int = 0
total_tokens: int = 0
class ChatCompletion(BaseModel):
"""Non-streaming chat completion response."""
id: str = Field(default_factory=lambda: f"chatcmpl-{uuid.uuid4().hex[:12]}")
object: Literal["chat.completion"] = "chat.completion"
created: int = Field(default_factory=lambda: int(time.time()))
model: str = "default"
choices: list[CompletionChoice]
usage: CompletionUsage = Field(default_factory=CompletionUsage)