feat: expose background service lifecycle (#36895)
This commit is contained in:
Kit Langton
GitHub
parent
ea89a2f619
commit
ece2b16cdf
36 changed files with 2421 additions and 293 deletions
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@ -10,8 +10,17 @@ type StreamValue<A> = A extends Stream.Stream<infer Success, any, any> ? Success
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export type Endpoint0_0Output = EffectValue<ReturnType<RawClient["server.health"]["health.get"]>>
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export type HealthGetOperation<E = never> = () => Effect.Effect<Endpoint0_0Output, E>
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type Endpoint0_1Request = Parameters<RawClient["server.health"]["health.stop"]>[0]
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export type Endpoint0_1Input = {
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readonly instanceID: Endpoint0_1Request["payload"]["instanceID"]
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readonly targetVersion?: Endpoint0_1Request["payload"]["targetVersion"]
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}
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export type Endpoint0_1Output = EffectValue<ReturnType<RawClient["server.health"]["health.stop"]>>
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export type HealthStopOperation<E = never> = (input: Endpoint0_1Input) => Effect.Effect<Endpoint0_1Output, E>
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export interface HealthApi<E = never> {
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readonly get: HealthGetOperation<E>
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readonly stop: HealthStopOperation<E>
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}
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export type Endpoint1_0Output = EffectValue<ReturnType<RawClient["server.server"]["server.get"]>>
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@ -16,7 +16,17 @@ const mapClientError = <E>(error: E) =>
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const Endpoint0_0 = (raw: RawClient["server.health"]) => () =>
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raw["health.get"]({}).pipe(Effect.mapError(mapClientError))
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const adaptGroup0 = (raw: RawClient["server.health"]) => ({ get: Endpoint0_0(raw) })
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type Endpoint0_1Request = Parameters<RawClient["server.health"]["health.stop"]>[0]
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type Endpoint0_1Input = {
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readonly instanceID: Endpoint0_1Request["payload"]["instanceID"]
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readonly targetVersion?: Endpoint0_1Request["payload"]["targetVersion"]
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}
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const Endpoint0_1 = (raw: RawClient["server.health"]) => (input: Endpoint0_1Input) =>
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raw["health.stop"]({ payload: { instanceID: input["instanceID"], targetVersion: input["targetVersion"] } }).pipe(
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Effect.mapError(mapClientError),
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)
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const adaptGroup0 = (raw: RawClient["server.health"]) => ({ get: Endpoint0_0(raw), stop: Endpoint0_1(raw) })
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const Endpoint1_0 = (raw: RawClient["server.server"]) => () =>
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raw["server.get"]({}).pipe(Effect.mapError(mapClientError))
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@ -1,5 +1,6 @@
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import { ServiceStatus } from "@opencode-ai/protocol/groups/health"
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import { Effect, FileSystem, Option, Schedule, Schema } from "effect"
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import { spawn } from "node:child_process"
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import { spawn, type ChildProcess } from "node:child_process"
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import { homedir } from "node:os"
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import { join } from "node:path"
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@ -39,6 +40,23 @@ export type StartOptions = Options & {
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// found, or a healthy service with a different version is being replaced.
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// `existing` carries the registration of the service being replaced.
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readonly onStart?: (reason: StartReason, existing?: Info) => void
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readonly onStatus?: (status: Status) => void
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}
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export type Status =
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| { readonly type: "missing" }
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| { readonly type: "unreachable" }
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| { readonly type: "unresponsive" }
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| (ServiceStatus.State & { readonly version?: string })
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export class FailedError extends Schema.TaggedErrorClass<FailedError>()("ServiceFailedError", {
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message: Schema.String,
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action: Schema.String,
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}) {}
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type Contender = {
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readonly child: ChildProcess
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readonly error: () => Error | undefined
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}
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// Read-only lookup: registration file plus health check and version gate.
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@ -47,58 +65,138 @@ export const discover = Effect.fn("service.discover")(function* (options: Option
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return (yield* discoverLocal(options))?.endpoint
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})
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export const status = Effect.fn("service.status")(function* (options: Options = {}) {
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const result = yield* registered(options.file, true)
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if (result.info === undefined) return { type: "missing" } satisfies Status
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if (result.service === undefined) return { type: "unreachable" } satisfies Status
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return publicStatus(result.service)
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})
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function publicStatus(service: LocalService): Status {
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return { ...service.status, version: service.version }
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}
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const discoverLocal = Effect.fnUntraced(function* (options: Options) {
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const info = yield* read(options.file)
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if (info === undefined) return undefined
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if (options.version !== undefined && info.version !== options.version) return undefined
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return yield* probe(info, options.version)
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const found = (yield* registered(options.file)).service
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if (found?.status.type !== "ready") return undefined
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if (options.version !== undefined && found.version !== options.version) return undefined
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return found
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})
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// Idempotent ensure-running: reuses a healthy compatible server, replaces a
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// version-mismatched one, and otherwise spawns the service command detached.
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// version-mismatched one, and otherwise spawns small contenders until a server
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// becomes discoverable. A contender is never killed merely for slow startup.
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export const start = Effect.fn("service.start")(function* (options: StartOptions = {}) {
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const compatible = yield* discover(options)
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if (compatible !== undefined) return compatible
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const existing = yield* find(options)
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if (existing?.version !== undefined && (options.version === undefined || existing.version === options.version))
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return existing.endpoint
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yield* Effect.sync(() => options.onStart?.(existing === undefined ? "missing" : "version-mismatch", existing?.info))
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if (existing !== undefined) yield* kill(existing.info, options).pipe(Effect.ignore)
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const [command, ...args] = options.command ?? ["opencode", "serve", "--service"]
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if (command === undefined) return yield* Effect.fail(new Error("Missing service command"))
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const child = yield* Effect.try({
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try: () => {
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const child = spawn(command, args, { detached: true, stdio: "ignore" })
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child.unref()
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return child
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},
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catch: (cause) => new Error("Failed to start server", { cause }),
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const contenders = new Set<Contender>()
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let announced = false
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let reported: Status | undefined
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let lastSpawn = 0
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let spawnDelay = 5_000
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let ownerHeld = false
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const announce = (reason: StartReason, existing?: Info) =>
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Effect.sync(() => {
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if (announced) return
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announced = true
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options.onStart?.(reason, existing)
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})
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const spawnContender = Effect.gen(function* () {
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const [command, ...args] = options.command ?? ["opencode", "serve", "--service"]
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if (command === undefined) return yield* Effect.fail(new Error("Missing service command"))
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return yield* Effect.try({
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try: () => {
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const child = spawn(command, args, { detached: true, stdio: "ignore" })
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let error: Error | undefined
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child.once("error", (cause) => {
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error = new Error("Failed to start server", { cause })
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})
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child.unref()
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return { child, error: () => error }
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},
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catch: (cause) => new Error("Failed to start server", { cause }),
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})
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})
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const found = yield* Effect.gen(function* () {
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const registration = yield* registered(options.file, true)
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const info = registration.info
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const service = registration.service
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const current: Status =
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service === undefined ? { type: info === undefined ? "missing" : "unreachable" } : publicStatus(service)
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const next = ownerHeld && service === undefined ? ({ type: "unresponsive" } satisfies Status) : current
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yield* Effect.sync(() => {
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if (sameStatus(reported, next)) return
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reported = next
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options.onStatus?.(next)
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})
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if (service !== undefined) {
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ownerHeld = false
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spawnDelay = 5_000
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const compatible = !service.legacy && (options.version === undefined || service.version === options.version)
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if (compatible && service.status.type === "ready") return Option.some(service)
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if (compatible && service.status.type === "failed")
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return yield* new FailedError({ message: service.status.message, action: service.status.action })
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if (compatible || service.status.type === "stopping") return Option.none<LocalService>()
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yield* announce("version-mismatch", service.info)
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yield* kill(service, options, options.version).pipe(Effect.ignore)
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lastSpawn = 0
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return Option.none<LocalService>()
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} else if (lastSpawn === 0 && info !== undefined) lastSpawn = Date.now()
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return yield* discoverLocal(options).pipe(
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Effect.flatMap((found) =>
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found === undefined ? Effect.fail(new Error("Server is not ready")) : Effect.succeed(found),
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),
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Effect.retry(poll),
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Effect.tap((found) =>
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found.info.pid === child.pid
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? Effect.void
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: Effect.sync(() => {
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child.kill("SIGTERM")
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}),
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),
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Effect.map((found) => found.endpoint),
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Effect.tapError(() => Effect.try({ try: () => child.kill("SIGTERM"), catch: () => undefined }).pipe(Effect.ignore)),
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Effect.mapError(() => new Error("Failed to start server")),
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)
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const failure = [...contenders].map(contenderFailure).find((error): error is Error => error !== undefined)
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if (failure !== undefined) return yield* Effect.fail(failure)
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const finished = [...contenders].filter(contenderFinished)
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if (finished.some((item) => item.child.exitCode === 0)) {
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ownerHeld = true
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spawnDelay = Math.min(spawnDelay * 2, 30_000)
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}
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finished.forEach((item) => contenders.delete(item))
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// Keep one candidate plus one lock probe so a pre-lock stall cannot block recovery.
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if (contenders.size < 2 && Date.now() - lastSpawn >= spawnDelay) {
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yield* announce("missing")
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contenders.add(yield* spawnContender)
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lastSpawn = Date.now()
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}
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return Option.none<LocalService>()
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}).pipe(Effect.repeat({ until: Option.isSome, schedule: Schedule.spaced("1 second") }))
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return Option.getOrThrow(found).endpoint
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})
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export const stop = Effect.fn("service.stop")(function* (options: Options = {}) {
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const fs = yield* FileSystem.FileSystem
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function sameStatus(left: Status | undefined, right: Status) {
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if (left?.type !== right.type) return false
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if (right.type === "failed")
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return (
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left.type === "failed" &&
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left.version === right.version &&
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left.message === right.message &&
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left.action === right.action
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)
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if (right.type === "stopping")
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return left.type === "stopping" && left.version === right.version && left.targetVersion === right.targetVersion
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if (right.type === "starting" || right.type === "ready")
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return left.type === right.type && left.version === right.version
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return true
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}
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function contenderFailure(contender: Contender) {
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const error = contender.error()
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if (error !== undefined) return error
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if (contender.child.exitCode !== null && contender.child.exitCode !== 0)
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return new Error(`Server process exited with code ${contender.child.exitCode}`)
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if (contender.child.signalCode !== null)
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return new Error(`Server process terminated by ${contender.child.signalCode}`)
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return undefined
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}
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function contenderFinished(contender: Contender) {
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return contender.error() !== undefined || contender.child.exitCode !== null || contender.child.signalCode !== null
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}
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export type StopMetadata = {
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readonly targetVersion?: string
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}
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export const stop = Effect.fn("service.stop")(function* (options: Options = {}, metadata: StopMetadata = {}) {
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const existing = yield* find(options)
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if (existing !== undefined) yield* kill(existing.info, options)
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yield* fs.remove(options.file ?? fallback()).pipe(Effect.ignore)
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if (existing !== undefined) yield* kill(existing, options, metadata.targetVersion)
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})
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function fallback() {
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@ -106,7 +204,7 @@ function fallback() {
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return join(state, "opencode", "service.json")
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}
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export function headers(endpoint: Endpoint): RequestInit["headers"] {
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export function headers(endpoint: Endpoint) {
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if (endpoint.auth === undefined) return undefined
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return { authorization: "Basic " + btoa(endpoint.auth.username + ":" + endpoint.auth.password) }
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}
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@ -121,9 +219,7 @@ export const Info = Schema.Struct({
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export type Info = typeof Info.Type
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const decode = Schema.decodeUnknownEffect(Schema.fromJsonString(Info))
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const decodeHealth = Schema.decodeUnknownOption(
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Schema.Struct({ healthy: Schema.Literal(true), version: Schema.String, pid: Schema.Int }),
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)
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const decodeHealth = Schema.decodeUnknownOption(ServiceStatus.Health)
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const decodeLegacyHealth = Schema.decodeUnknownOption(Schema.Struct({ healthy: Schema.Literal(true) }))
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// A missing or corrupt file means no valid info; callers treat both
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@ -139,9 +235,11 @@ type LocalService = {
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readonly info: Info
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readonly endpoint: Endpoint
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readonly version?: string
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readonly status: ServiceStatus.State
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readonly legacy: boolean
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}
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const probe = Effect.fnUntraced(function* (info: Info, version?: string, allowLegacy = false) {
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const probe = Effect.fnUntraced(function* (info: Info, allowLegacy = false) {
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const endpoint = {
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url: info.url,
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auth:
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@ -155,14 +253,21 @@ const probe = Effect.fnUntraced(function* (info: Info, version?: string, allowLe
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signal: AbortSignal.timeout(2_000),
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}),
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).pipe(Effect.option, Effect.map(Option.getOrUndefined))
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if (response === undefined || !response.ok) return undefined
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if (response === undefined) return undefined
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const body = yield* Effect.tryPromise(() => response.json()).pipe(Effect.option, Effect.map(Option.getOrUndefined))
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const health = decodeHealth(body)
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if (Option.isSome(health)) {
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if (health.value.pid !== info.pid) return undefined
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if (info.version !== undefined && health.value.version !== info.version) return undefined
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if (version !== undefined && health.value.version !== version) return undefined
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return { info, endpoint, version: health.value.version } satisfies LocalService
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if (info.id !== undefined && health.value.instanceID !== undefined && health.value.instanceID !== info.id)
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return undefined
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return {
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info,
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endpoint,
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version: health.value.version,
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status: health.value.status,
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legacy: false,
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} satisfies LocalService
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}
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if (
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!allowLegacy ||
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@ -170,18 +275,23 @@ const probe = Effect.fnUntraced(function* (info: Info, version?: string, allowLe
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(typeof body === "object" && body !== null && ("version" in body || "pid" in body))
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)
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return undefined
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return { info, endpoint } satisfies LocalService
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return { info, endpoint, status: { type: "ready" }, legacy: true } satisfies LocalService
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})
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// Health-checked lookup without the version gate: lifecycle operations must be
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const registered = Effect.fnUntraced(function* (file?: string, allowLegacy = false) {
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const info = yield* read(file)
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if (info === undefined) return { info: undefined, service: undefined }
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return { info, service: yield* probe(info, allowLegacy) }
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})
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// Health-checked lookup without the version gate: status operations must be
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// able to see (and replace or stop) a server from a different version.
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const find = Effect.fnUntraced(function* (options: Options) {
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const info = yield* read(options.file)
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if (info === undefined) return undefined
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return yield* probe(info, undefined, true)
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return (yield* registered(options.file, true)).service
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})
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// 50ms cadence bounded at ~5s, shared by stop escalation and start readiness.
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// 50ms cadence bounded at ~5s, shared by stop escalation and each start
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// discovery window.
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const poll = Schedule.spaced("50 millis").pipe(Schedule.both(Schedule.recurs(100)))
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const signal = (pid: number, name: NodeJS.Signals) =>
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@ -199,20 +309,42 @@ function same(left: Info, right: Info) {
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return left.id === right.id && left.version === right.version && left.url === right.url && left.pid === right.pid
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}
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const kill = Effect.fnUntraced(function* (info: Info, options: Options) {
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// A stale registration may point at a PID that has since been reused by
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// another process. Only signal the PID after authenticating the server.
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const current = yield* find(options)
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if (current === undefined || !same(current.info, info)) return
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yield* signal(info.pid, "SIGTERM")
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const done = yield* stopped(info.pid).pipe(Effect.retry(poll), Effect.option)
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const kill = Effect.fnUntraced(function* (service: LocalService, options: Options, targetVersion?: string) {
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const requested = yield* requestStop(service, targetVersion)
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if (requested === "rejected") return
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if (requested === "unsupported") {
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// A stale registration may point at a reused PID. Authenticate again
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// immediately before the legacy signal fallback.
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const current = yield* find(options)
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if (current === undefined || !same(current.info, service.info)) return
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yield* signal(service.info.pid, "SIGTERM")
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}
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const done = yield* stopped(service.info.pid).pipe(Effect.retry(poll), Effect.option)
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if (Option.isSome(done)) return
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const latest = yield* find(options)
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if (latest === undefined || !same(latest.info, info)) return
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yield* signal(info.pid, "SIGKILL")
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yield* stopped(info.pid).pipe(Effect.retry(poll))
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if (latest === undefined || !same(latest.info, service.info)) return
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yield* signal(service.info.pid, "SIGKILL")
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yield* stopped(service.info.pid).pipe(Effect.retry(poll))
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})
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const decodeStopResponse = Schema.decodeUnknownOption(ServiceStatus.StopResponse)
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const requestStop = Effect.fnUntraced(function* (service: LocalService, targetVersion?: string) {
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if (service.info.id === undefined || service.legacy) return "unsupported" as const
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const response = yield* Effect.tryPromise(() =>
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fetch(new URL("/api/service/stop", service.info.url), {
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method: "POST",
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headers: { ...headers(service.endpoint), "content-type": "application/json" },
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body: JSON.stringify({ instanceID: service.info.id, targetVersion }),
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signal: AbortSignal.timeout(2_000),
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}),
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).pipe(Effect.option, Effect.map(Option.getOrUndefined))
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if (response === undefined || response.status === 404 || response.status === 405) return "unsupported" as const
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const body = yield* Effect.tryPromise(() => response.json()).pipe(Effect.option, Effect.map(Option.getOrUndefined))
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const decoded = decodeStopResponse(body)
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if (!response.ok || Option.isNone(decoded) || !decoded.value.accepted) return "rejected" as const
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return "accepted" as const
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})
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export * as Service from "./service.js"
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@ -1,5 +1,7 @@
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import type {
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HealthGetOutput,
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HealthStopInput,
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HealthStopOutput,
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ServerGetOutput,
|
||||
LocationGetInput,
|
||||
LocationGetOutput,
|
||||
|
|
@ -332,6 +334,18 @@ export function make(options: ClientOptions) {
|
|||
{ method: "GET", path: `/api/health`, successStatus: 200, declaredStatuses: [401, 400], empty: false },
|
||||
requestOptions,
|
||||
),
|
||||
stop: (input: HealthStopInput, requestOptions?: RequestOptions) =>
|
||||
request<HealthStopOutput>(
|
||||
{
|
||||
method: "POST",
|
||||
path: `/api/service/stop`,
|
||||
body: { instanceID: input["instanceID"], targetVersion: input["targetVersion"] },
|
||||
successStatus: 200,
|
||||
declaredStatuses: [401, 400],
|
||||
empty: false,
|
||||
},
|
||||
requestOptions,
|
||||
),
|
||||
},
|
||||
server: {
|
||||
get: (requestOptions?: RequestOptions) =>
|
||||
|
|
|
|||
|
|
@ -1,5 +1,13 @@
|
|||
export type JsonValue = null | boolean | number | string | Array<JsonValue> | { [key: string]: JsonValue }
|
||||
|
||||
export type ServiceStatus =
|
||||
| { type: "starting" }
|
||||
| { type: "ready" }
|
||||
| { type: "stopping"; targetVersion?: string | null }
|
||||
| { type: "failed"; message: string; action: string }
|
||||
|
||||
export type ServiceStopResponse = { accepted: boolean }
|
||||
|
||||
export type ModelRef = { id: string; providerID: string; variant?: string }
|
||||
|
||||
export type ProviderSettings = { [x: string]: JsonValue }
|
||||
|
|
@ -498,6 +506,14 @@ export type VcsFileStatus = {
|
|||
status: "added" | "deleted" | "modified"
|
||||
}
|
||||
|
||||
export type ServiceHealth = {
|
||||
healthy: true
|
||||
version: string
|
||||
pid: number
|
||||
instanceID?: string | null
|
||||
status?: ServiceStatus
|
||||
}
|
||||
|
||||
export type SessionMessageModelSelected = {
|
||||
id: string
|
||||
metadata?: { [x: string]: JsonValue }
|
||||
|
|
@ -2483,7 +2499,14 @@ export type ProjectCopyError = {
|
|||
export const isProjectCopyError = (value: unknown): value is ProjectCopyError =>
|
||||
typeof value === "object" && value !== null && "name" in value && value["name"] === "ProjectCopyError"
|
||||
|
||||
export type HealthGetOutput = { healthy: true; version: string; pid: number }
|
||||
export type HealthGetOutput = ServiceHealth
|
||||
|
||||
export type HealthStopInput = {
|
||||
readonly instanceID: { readonly instanceID: string; readonly targetVersion?: string | undefined }["instanceID"]
|
||||
readonly targetVersion?: { readonly instanceID: string; readonly targetVersion?: string | undefined }["targetVersion"]
|
||||
}
|
||||
|
||||
export type HealthStopOutput = ServiceStopResponse
|
||||
|
||||
export type ServerGetOutput = { urls: Array<string> }
|
||||
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue