fix(cli): elect managed service by port bind (#37572)

Co-authored-by: Dax Raad <thdxr@users.noreply.github.com>

packages/client/src/effect/service.ts

@@ -29,6 +29,17 @@ export const discover = Effect.fn("service.discover")(function* (options: Discov
   return (yield* discoverLocal(options))?.endpoint
 })
 
+/** Recognize an authenticated compatible service bound to an expected URL, including while it starts or fails. */
+export const incumbent = Effect.fn("service.incumbent")(function* (
+  options: DiscoverOptions & { readonly url: string },
+) {
+  const info = yield* read(options.file)
+  const found = info === undefined ? undefined : yield* probe({ ...info, url: options.url })
+  if (found === undefined || found.legacy) return undefined
+  if (options.version !== undefined && found.version !== options.version) return undefined
+  return { endpoint: found.endpoint, state: found.state }
+})
+
 const discoverLocal = Effect.fnUntraced(function* (options: DiscoverOptions) {
   const found = (yield* registered(options.file)).service
   if (found?.state !== "ready") return undefined
@@ -101,8 +112,15 @@ export const ensure = Effect.fn("service.ensure")(function* (options: EnsureOpti
       lastSpawn = Date.now()
     }
     return Option.none<LocalService>()
-  }).pipe(Effect.repeat({ until: Option.isSome, schedule: Schedule.spaced("1 second") }))
-  return Option.getOrThrow(found).endpoint
+  }).pipe(
+    Effect.repeat({
+      until: Option.isSome,
+      schedule: Schedule.max([Schedule.spaced("1 second"), Schedule.recurs(120)]),
+    }),
+  )
+  if (Option.isNone(found))
+    return yield* Effect.fail(new Error("Timed out waiting for the background service to start"))
+  return found.value.endpoint
 })
 
 function contenderFailure(contender: Contender) {
@@ -143,6 +161,7 @@ export const Info = Schema.Struct({
   url: Schema.String,
   pid: Schema.Int.check(Schema.isGreaterThan(0)),
   password: Schema.optional(Schema.String),
+  startedAt: Schema.optional(Schema.Int.check(Schema.isGreaterThan(0))),
 })
 
 const decode = Schema.decodeUnknownEffect(Schema.fromJsonString(Info))
@@ -273,4 +292,4 @@ const requestStop = Effect.fnUntraced(function* (service: LocalService) {
 })
 
 /** Effect-based local service lifecycle operations. */
-export const Service = { discover, ensure, stop, headers, Info }
+export const Service = { discover, incumbent, ensure, stop, headers, Info }

packages/client/src/promise/service.ts

@@ -2,13 +2,7 @@ import { readFile } from "node:fs/promises"
 import { spawn, type ChildProcess } from "node:child_process"
 import { homedir } from "node:os"
 import { join } from "node:path"
-import type {
-  DiscoverOptions,
-  Endpoint,
-  Info,
-  EnsureOptions,
-  StopOptions,
-} from "../service.js"
+import type { DiscoverOptions, Endpoint, Info, EnsureOptions, StopOptions } from "../service.js"
 import type { ServiceHealth, ServiceStopResponse } from "./generated/types.js"
 
 export * from "../service.js"
@@ -38,6 +32,7 @@ async function discoverLocal(options: DiscoverOptions) {
 
 /** Ensure a healthy, compatible local service is running. */
 export async function ensure(options: EnsureOptions = {}): Promise<Endpoint> {
+  const deadline = Date.now() + 120_000
   const contenders = new Set<Contender>()
   let announced = false
   let lastSpawn = 0
@@ -66,6 +61,7 @@ export async function ensure(options: EnsureOptions = {}): Promise<Endpoint> {
   }
 
   while (true) {
+    if (Date.now() >= deadline) throw new Error("Timed out waiting for the background service to start")
     const registration = await registered(options.file, true)
 
     if (registration.service !== undefined) {
@@ -128,7 +124,9 @@ function fallback() {
 /** Create HTTP authentication headers for a service endpoint. */
 export function headers(endpoint: Endpoint) {
   if (endpoint.auth === undefined) return undefined
-  return { authorization: "Basic " + Buffer.from(endpoint.auth.username + ":" + endpoint.auth.password).toString("base64") }
+  return {
+    authorization: "Basic " + Buffer.from(endpoint.auth.username + ":" + endpoint.auth.password).toString("base64"),
+  }
 }
 
 async function read(file?: string) {
@@ -227,7 +225,8 @@ async function kill(service: LocalService, options: { readonly file?: string })
   const latest = await find(options)
   if (latest === undefined || !same(latest.info, service.info)) return
   signal(service.info.pid, "SIGKILL")
-  if (!(await waitUntilStopped(service.info.pid))) throw new Error(`Server process ${service.info.pid} is still running`)
+  if (!(await waitUntilStopped(service.info.pid)))
+    throw new Error(`Server process ${service.info.pid} is still running`)
 }
 
 async function requestStop(service: LocalService) {

packages/client/src/service.ts

@@ -50,4 +50,6 @@ export type Info = {
   readonly pid: number
   /** Private service password, when authentication is enabled. */
   readonly password?: string
+  /** Registration generation used to resolve owner write races. */
+  readonly startedAt?: number
 }