Files
zmo-cli/packages/opencode/src/plugin/openai/ws-pool.ts

248 lines
8.2 KiB
TypeScript

import WebSocket from "ws"
import * as Log from "@opencode-ai/core/util/log"
import { isRecord } from "@/util/record"
import { OpenAIWebSocket } from "./ws"
export const TITLE_HEADER = "x-opencode-title"
const log = Log.create({ service: "plugin.openai.ws" })
export interface CreateWebSocketFetchOptions {
httpFetch?: typeof globalThis.fetch
url?: string
connectTimeout?: number
idleTimeout?: number
maxConnectionAge?: number
connectionLimitRetries?: number
}
interface PoolEntry {
socket?: WebSocket
connectedAt?: number
lastUsedAt: number
busy: boolean
fallback: boolean
}
const DEFAULT_CONNECT_TIMEOUT = 15_000
const DEFAULT_IDLE_TIMEOUT = 5 * 60 * 1000
const DEFAULT_MAX_CONNECTION_AGE = 55 * 60 * 1000
const CONNECTION_LIMIT_REACHED_CODE = "websocket_connection_limit_reached"
export function createWebSocketFetch(options?: CreateWebSocketFetchOptions) {
const httpFetch = options?.httpFetch ?? globalThis.fetch
const pool = new Map<string, PoolEntry>()
const connectTimeout = options?.connectTimeout ?? DEFAULT_CONNECT_TIMEOUT
const idleTimeout = options?.idleTimeout ?? DEFAULT_IDLE_TIMEOUT
const maxConnectionAge = options?.maxConnectionAge ?? DEFAULT_MAX_CONNECTION_AGE
const connectionLimitRetries = options?.connectionLimitRetries ?? 5
const pruneTimer = setInterval(() => prune(), Math.min(idleTimeout, 60_000))
if (typeof pruneTimer === "object" && "unref" in pruneTimer && typeof pruneTimer.unref === "function") {
pruneTimer.unref()
}
async function websocketFetch(input: RequestInfo | URL, init?: RequestInit): Promise<Response> {
const url = input instanceof URL ? input.toString() : typeof input === "string" ? input : input.url
const internalHeaders = OpenAIWebSocket.normalizeHeaders(init?.headers)
const httpInit = withoutInternalHeaders(init)
if (init?.method !== "POST" || !new URL(url).pathname.endsWith("/responses")) {
return httpFetch(input, httpInit)
}
const body = (() => {
try {
if (typeof init?.body !== "string") return undefined
const parsed = JSON.parse(init.body)
return typeof parsed === "object" && parsed !== null ? parsed : undefined
} catch {
return undefined
}
})()
if (!body?.stream) return httpFetch(input, httpInit)
if (internalHeaders[TITLE_HEADER] === "true") {
log.debug("http fallback", { reason: "title" })
return httpFetch(input, httpInit)
}
const sessionID = internalHeaders["x-session-affinity"] ?? internalHeaders["session-id"]
if (!sessionID) {
log.debug("http fallback", { reason: "missing_session" })
return httpFetch(input, httpInit)
}
const key = `${sessionID}:conversation`
const entry = pool.get(key) ?? { lastUsedAt: Date.now(), busy: false, fallback: false }
pool.set(key, entry)
if (entry.fallback) {
log.debug("http fallback", { key, reason: "fallback_active" })
return httpFetch(input, httpInit)
}
if (entry.busy) {
log.debug("http fallback", { key, reason: "busy" })
return httpFetch(input, httpInit)
}
entry.busy = true
entry.lastUsedAt = Date.now()
try {
let connectionLimitAttempts = 0
entry.socket = await socket(
entry,
options?.url ?? url,
OpenAIWebSocket.normalizeHeaders(httpInit?.headers),
connectTimeout,
maxConnectionAge,
init?.signal,
)
let resolveFirstEvent: (started: boolean) => void = () => {}
let rejectFirstEvent: (error: Error) => void = () => {}
const firstEvent = new Promise<boolean>((resolve, reject) => {
resolveFirstEvent = resolve
rejectFirstEvent = reject
})
const response = OpenAIWebSocket.streamResponsesWebSocket({
socket: entry.socket,
body,
idleTimeout,
signal: init?.signal ?? undefined,
onFirstEvent: () => resolveFirstEvent(true),
onTerminal: (event) => {
entry.busy = false
entry.lastUsedAt = Date.now()
if (event.type !== "response.completed" && event.type !== "response.done") {
log.warn("websocket terminal failure", { key, type: event.type })
invalidate(entry)
}
},
onConnectionInvalid: (error) => {
log.warn("websocket invalidated", { key, error: error instanceof Error ? error.message : String(error) })
entry.busy = false
entry.fallback = true
invalidate(entry)
resolveFirstEvent(false)
},
onAbort: (error) => {
log.debug("websocket aborted", { key })
entry.busy = false
entry.lastUsedAt = Date.now()
invalidate(entry)
rejectFirstEvent(error)
},
onRetryableTerminal: async (event) => {
const error = connectionLimitError(event)
if (!error) return undefined
if (connectionLimitAttempts >= connectionLimitRetries) throw error
connectionLimitAttempts++
log.warn("websocket connection limit reached", { key, attempt: connectionLimitAttempts })
invalidate(entry)
entry.socket = await socket(
entry,
options?.url ?? url,
OpenAIWebSocket.normalizeHeaders(httpInit?.headers),
connectTimeout,
maxConnectionAge,
init?.signal,
)
entry.lastUsedAt = Date.now()
return entry.socket
},
})
if (await firstEvent) return response
log.debug("http fallback", { key, reason: "websocket_failed_before_first_event" })
return httpFetch(input, httpInit)
} catch (error) {
entry.busy = false
entry.lastUsedAt = Date.now()
if (OpenAIWebSocket.isAbortError(error)) {
invalidate(entry)
throw error
}
entry.fallback = true
log.warn("websocket setup failed", { key, error: error instanceof Error ? error.message : String(error), fallback: "http" })
invalidate(entry)
return httpFetch(input, httpInit)
}
}
function prune() {
const now = Date.now()
for (const [key, entry] of pool) {
if (entry.busy) continue
if (now - entry.lastUsedAt < idleTimeout) continue
log.debug("websocket idle prune", { key })
invalidate(entry)
pool.delete(key)
}
}
function close() {
log.debug("websocket pool close", { count: pool.size })
clearInterval(pruneTimer)
for (const entry of pool.values()) invalidate(entry)
pool.clear()
}
return Object.assign(websocketFetch, { close })
}
function connectionLimitError(event: Record<string, unknown>) {
if (event.type !== "error" || !isRecord(event.error) || event.error.code !== CONNECTION_LIMIT_REACHED_CODE) return
return new Error(typeof event.error.message === "string" ? event.error.message : CONNECTION_LIMIT_REACHED_CODE)
}
async function socket(
entry: PoolEntry,
url: string,
headers: Record<string, string>,
connectTimeout: number,
maxConnectionAge: number,
signal?: AbortSignal | null,
) {
if (entry.socket?.readyState === WebSocket.OPEN && entry.connectedAt && Date.now() - entry.connectedAt < maxConnectionAge) {
return entry.socket
}
invalidate(entry)
const next = await OpenAIWebSocket.connectResponsesWebSocket({
url: OpenAIWebSocket.toWebSocketUrl(url),
headers,
timeout: connectTimeout,
signal: signal ?? undefined,
})
entry.connectedAt = Date.now()
return next
}
function invalidate(entry: PoolEntry) {
if (entry.socket) {
entry.socket.on("error", () => {})
entry.socket.terminate()
entry.socket = undefined
}
entry.connectedAt = undefined
}
export function withoutInternalHeaders<T extends { headers?: HeadersInit }>(init: T | undefined): T | undefined {
if (!init?.headers) return init
if (init.headers instanceof Headers) {
const headers = new Headers(init.headers)
headers.delete(TITLE_HEADER)
return { ...init, headers }
}
if (Array.isArray(init.headers)) {
return { ...init, headers: init.headers.filter((item) => item[0].toLowerCase() !== TITLE_HEADER) }
}
return {
...init,
headers: Object.fromEntries(Object.entries(init.headers).filter(([key]) => key.toLowerCase() !== TITLE_HEADER)),
}
}
export * as OpenAIWebSocketPool from "./ws-pool"