stack: effectify-file-watcher-service (#17827)

packages/opencode/src/effect/instances.ts

@@ -3,6 +3,7 @@ import { registerDisposer } from "./instance-registry"
 import { ProviderAuthService } from "@/provider/auth-service"
 import { QuestionService } from "@/question/service"
 import { PermissionService } from "@/permission/service"
+import { FileWatcherService } from "@/file/watcher"
 import { Instance } from "@/project/instance"
 import type { Project } from "@/project/project"
 
@@ -17,7 +18,7 @@ export class InstanceContext extends ServiceMap.Service<InstanceContext, Instanc
   "opencode/InstanceContext",
 ) {}
 
-export type InstanceServices = QuestionService | PermissionService | ProviderAuthService
+export type InstanceServices = QuestionService | PermissionService | ProviderAuthService | FileWatcherService
 
 function lookup(directory: string) {
   const project = Instance.project
@@ -26,6 +27,7 @@ function lookup(directory: string) {
     Layer.fresh(QuestionService.layer),
     Layer.fresh(PermissionService.layer),
     Layer.fresh(ProviderAuthService.layer),
+    Layer.fresh(FileWatcherService.layer),
   ).pipe(Layer.provide(ctx))
 }
 

packages/opencode/src/file/watcher.ts

@@ -1,7 +1,8 @@
 import { BusEvent } from "@/bus/bus-event"
 import { Bus } from "@/bus"
+import { InstanceContext } from "@/effect/instances"
+import { Instance } from "@/project/instance"
 import z from "zod"
-import { Instance } from "../project/instance"
 import { Log } from "../util/log"
 import { FileIgnore } from "./ignore"
 import { Config } from "../config/config"
@@ -9,118 +10,139 @@ import path from "path"
 // @ts-ignore
 import { createWrapper } from "@parcel/watcher/wrapper"
 import { lazy } from "@/util/lazy"
-import { withTimeout } from "@/util/timeout"
 import type ParcelWatcher from "@parcel/watcher"
-import { Flag } from "@/flag/flag"
 import { readdir } from "fs/promises"
 import { git } from "@/util/git"
 import { Protected } from "./protected"
+import { Flag } from "@/flag/flag"
+import { Cause, Effect, Layer, ServiceMap } from "effect"
 
 const SUBSCRIBE_TIMEOUT_MS = 10_000
 
 declare const OPENCODE_LIBC: string | undefined
 
-export namespace FileWatcher {
-  const log = Log.create({ service: "file.watcher" })
+const log = Log.create({ service: "file.watcher" })
 
-  export const Event = {
-    Updated: BusEvent.define(
-      "file.watcher.updated",
-      z.object({
-        file: z.string(),
-        event: z.union([z.literal("add"), z.literal("change"), z.literal("unlink")]),
-      }),
-    ),
+const event = {
+  Updated: BusEvent.define(
+    "file.watcher.updated",
+    z.object({
+      file: z.string(),
+      event: z.union([z.literal("add"), z.literal("change"), z.literal("unlink")]),
+    }),
+  ),
+}
+
+const watcher = lazy((): typeof import("@parcel/watcher") | undefined => {
+  try {
+    const binding = require(
+      `@parcel/watcher-${process.platform}-${process.arch}${process.platform === "linux" ? `-${OPENCODE_LIBC || "glibc"}` : ""}`,
+    )
+    return createWrapper(binding) as typeof import("@parcel/watcher")
+  } catch (error) {
+    log.error("failed to load watcher binding", { error })
+    return
   }
+})
 
-  const watcher = lazy((): typeof import("@parcel/watcher") | undefined => {
-    try {
-      const binding = require(
-        `@parcel/watcher-${process.platform}-${process.arch}${process.platform === "linux" ? `-${OPENCODE_LIBC || "glibc"}` : ""}`,
-      )
-      return createWrapper(binding) as typeof import("@parcel/watcher")
-    } catch (error) {
-      log.error("failed to load watcher binding", { error })
-      return
-    }
-  })
+function getBackend() {
+  if (process.platform === "win32") return "windows"
+  if (process.platform === "darwin") return "fs-events"
+  if (process.platform === "linux") return "inotify"
+}
 
-  const state = Instance.state(
-    async () => {
-      log.info("init")
-      const cfg = await Config.get()
-      const backend = (() => {
-        if (process.platform === "win32") return "windows"
-        if (process.platform === "darwin") return "fs-events"
-        if (process.platform === "linux") return "inotify"
-      })()
-      if (!backend) {
-        log.error("watcher backend not supported", { platform: process.platform })
-        return {}
-      }
-      log.info("watcher backend", { platform: process.platform, backend })
+export namespace FileWatcher {
+  export const Event = event
+  /** Whether the native @parcel/watcher binding is available on this platform. */
+  export const hasNativeBinding = () => !!watcher()
+}
 
-      const w = watcher()
-      if (!w) return {}
+const init = Effect.fn("FileWatcherService.init")(function* () {})
 
-      const subscribe: ParcelWatcher.SubscribeCallback = (err, evts) => {
-        if (err) return
-        for (const evt of evts) {
-          if (evt.type === "create") Bus.publish(Event.Updated, { file: evt.path, event: "add" })
-          if (evt.type === "update") Bus.publish(Event.Updated, { file: evt.path, event: "change" })
-          if (evt.type === "delete") Bus.publish(Event.Updated, { file: evt.path, event: "unlink" })
-        }
-      }
-
-      const subs: ParcelWatcher.AsyncSubscription[] = []
-      const cfgIgnores = cfg.watcher?.ignore ?? []
-
-      if (Flag.OPENCODE_EXPERIMENTAL_FILEWATCHER) {
-        const pending = w.subscribe(Instance.directory, subscribe, {
-          ignore: [...FileIgnore.PATTERNS, ...cfgIgnores, ...Protected.paths()],
-          backend,
-        })
-        const sub = await withTimeout(pending, SUBSCRIBE_TIMEOUT_MS).catch((err) => {
-          log.error("failed to subscribe to Instance.directory", { error: err })
-          pending.then((s) => s.unsubscribe()).catch(() => {})
-          return undefined
-        })
-        if (sub) subs.push(sub)
-      }
-
-      if (Instance.project.vcs === "git") {
-        const result = await git(["rev-parse", "--git-dir"], {
-          cwd: Instance.worktree,
-        })
-        const vcsDir = result.exitCode === 0 ? path.resolve(Instance.worktree, result.text().trim()) : undefined
-        if (vcsDir && !cfgIgnores.includes(".git") && !cfgIgnores.includes(vcsDir)) {
-          const gitDirContents = await readdir(vcsDir).catch(() => [])
-          const ignoreList = gitDirContents.filter((entry) => entry !== "HEAD")
-          const pending = w.subscribe(vcsDir, subscribe, {
-            ignore: ignoreList,
-            backend,
-          })
-          const sub = await withTimeout(pending, SUBSCRIBE_TIMEOUT_MS).catch((err) => {
-            log.error("failed to subscribe to vcsDir", { error: err })
-            pending.then((s) => s.unsubscribe()).catch(() => {})
-            return undefined
-          })
-          if (sub) subs.push(sub)
-        }
-      }
-
-      return { subs }
-    },
-    async (state) => {
-      if (!state.subs) return
-      await Promise.all(state.subs.map((sub) => sub?.unsubscribe()))
-    },
-  )
-
-  export function init() {
-    if (Flag.OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER) {
-      return
-    }
-    state()
+export namespace FileWatcherService {
+  export interface Service {
+    readonly init: () => Effect.Effect<void>
   }
 }
+
+export class FileWatcherService extends ServiceMap.Service<FileWatcherService, FileWatcherService.Service>()(
+  "@opencode/FileWatcher",
+) {
+  static readonly layer = Layer.effect(
+    FileWatcherService,
+    Effect.gen(function* () {
+      const instance = yield* InstanceContext
+      if (yield* Flag.OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER) return FileWatcherService.of({ init })
+
+      log.info("init", { directory: instance.directory })
+
+      const backend = getBackend()
+      if (!backend) {
+        log.error("watcher backend not supported", { directory: instance.directory, platform: process.platform })
+        return FileWatcherService.of({ init })
+      }
+
+      const w = watcher()
+      if (!w) return FileWatcherService.of({ init })
+
+      log.info("watcher backend", { directory: instance.directory, platform: process.platform, backend })
+
+      const subs: ParcelWatcher.AsyncSubscription[] = []
+      yield* Effect.addFinalizer(() => Effect.promise(() => Promise.allSettled(subs.map((sub) => sub.unsubscribe()))))
+
+      const cb: ParcelWatcher.SubscribeCallback = Instance.bind((err, evts) => {
+        if (err) return
+        for (const evt of evts) {
+          if (evt.type === "create") Bus.publish(event.Updated, { file: evt.path, event: "add" })
+          if (evt.type === "update") Bus.publish(event.Updated, { file: evt.path, event: "change" })
+          if (evt.type === "delete") Bus.publish(event.Updated, { file: evt.path, event: "unlink" })
+        }
+      })
+
+      const subscribe = (dir: string, ignore: string[]) => {
+        const pending = w.subscribe(dir, cb, { ignore, backend })
+        return Effect.gen(function* () {
+          const sub = yield* Effect.promise(() => pending)
+          subs.push(sub)
+        }).pipe(
+          Effect.timeout(SUBSCRIBE_TIMEOUT_MS),
+          Effect.catchCause((cause) => {
+            log.error("failed to subscribe", { dir, cause: Cause.pretty(cause) })
+            // Clean up a subscription that resolves after timeout
+            pending.then((s) => s.unsubscribe()).catch(() => {})
+            return Effect.void
+          }),
+        )
+      }
+
+      const cfg = yield* Effect.promise(() => Config.get())
+      const cfgIgnores = cfg.watcher?.ignore ?? []
+
+      if (yield* Flag.OPENCODE_EXPERIMENTAL_FILEWATCHER) {
+        yield* subscribe(instance.directory, [...FileIgnore.PATTERNS, ...cfgIgnores, ...Protected.paths()])
+      }
+
+      if (instance.project.vcs === "git") {
+        const result = yield* Effect.promise(() =>
+          git(["rev-parse", "--git-dir"], {
+            cwd: instance.project.worktree,
+          }),
+        )
+        const vcsDir = result.exitCode === 0 ? path.resolve(instance.project.worktree, result.text().trim()) : undefined
+        if (vcsDir && !cfgIgnores.includes(".git") && !cfgIgnores.includes(vcsDir)) {
+          const ignore = (yield* Effect.promise(() => readdir(vcsDir).catch(() => []))).filter(
+            (entry) => entry !== "HEAD",
+          )
+          yield* subscribe(vcsDir, ignore)
+        }
+      }
+
+      return FileWatcherService.of({ init })
+    }).pipe(
+      Effect.catchCause((cause) => {
+        log.error("failed to init watcher service", { cause: Cause.pretty(cause) })
+        return Effect.succeed(FileWatcherService.of({ init }))
+      }),
+    ),
+  )
+}

packages/opencode/src/flag/flag.ts

@@ -1,3 +1,5 @@
+import { Config } from "effect"
+
 function truthy(key: string) {
   const value = process.env[key]?.toLowerCase()
   return value === "true" || value === "1"
@@ -40,8 +42,12 @@ export namespace Flag {
 
   // Experimental
   export const OPENCODE_EXPERIMENTAL = truthy("OPENCODE_EXPERIMENTAL")
-  export const OPENCODE_EXPERIMENTAL_FILEWATCHER = truthy("OPENCODE_EXPERIMENTAL_FILEWATCHER")
-  export const OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER = truthy("OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER")
+  export const OPENCODE_EXPERIMENTAL_FILEWATCHER = Config.boolean("OPENCODE_EXPERIMENTAL_FILEWATCHER").pipe(
+    Config.withDefault(false),
+  )
+  export const OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER = Config.boolean(
+    "OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER",
+  ).pipe(Config.withDefault(false))
   export const OPENCODE_EXPERIMENTAL_ICON_DISCOVERY =
     OPENCODE_EXPERIMENTAL || truthy("OPENCODE_EXPERIMENTAL_ICON_DISCOVERY")
 

packages/opencode/src/project/bootstrap.ts

@@ -1,7 +1,7 @@
 import { Plugin } from "../plugin"
 import { Format } from "../format"
 import { LSP } from "../lsp"
-import { FileWatcher } from "../file/watcher"
+import { FileWatcherService } from "../file/watcher"
 import { File } from "../file"
 import { Project } from "./project"
 import { Bus } from "../bus"
@@ -12,6 +12,7 @@ import { Log } from "@/util/log"
 import { ShareNext } from "@/share/share-next"
 import { Snapshot } from "../snapshot"
 import { Truncate } from "../tool/truncation"
+import { runPromiseInstance } from "@/effect/runtime"
 
 export async function InstanceBootstrap() {
   Log.Default.info("bootstrapping", { directory: Instance.directory })
@@ -19,7 +20,7 @@ export async function InstanceBootstrap() {
   ShareNext.init()
   Format.init()
   await LSP.init()
-  FileWatcher.init()
+  await runPromiseInstance(FileWatcherService.use((service) => service.init()))
   File.init()
   Vcs.init()
   Snapshot.init()

packages/opencode/src/project/instance.ts

@@ -101,6 +101,15 @@ export const Instance = {
     if (Instance.worktree === "/") return false
     return Filesystem.contains(Instance.worktree, filepath)
   },
+  /**
+   * Captures the current instance ALS context and returns a wrapper that
+   * restores it when called. Use this for callbacks that fire outside the
+   * instance async context (native addons, event emitters, timers, etc.).
+   */
+  bind<F extends (...args: any[]) => any>(fn: F): F {
+    const ctx = context.use()
+    return ((...args: any[]) => context.provide(ctx, () => fn(...args))) as F
+  },
   state<S>(init: () => S, dispose?: (state: Awaited<S>) => Promise<void>): () => S {
     return State.create(() => Instance.directory, init, dispose)
   },

packages/opencode/src/pty/index.ts

@@ -167,40 +167,44 @@ export namespace Pty {
       subscribers: new Map(),
     }
     state().set(id, session)
-    ptyProcess.onData((chunk) => {
-      session.cursor += chunk.length
+    ptyProcess.onData(
+      Instance.bind((chunk) => {
+        session.cursor += chunk.length
 
-      for (const [key, ws] of session.subscribers.entries()) {
-        if (ws.readyState !== 1) {
-          session.subscribers.delete(key)
-          continue
+        for (const [key, ws] of session.subscribers.entries()) {
+          if (ws.readyState !== 1) {
+            session.subscribers.delete(key)
+            continue
+          }
+
+          if (ws.data !== key) {
+            session.subscribers.delete(key)
+            continue
+          }
+
+          try {
+            ws.send(chunk)
+          } catch {
+            session.subscribers.delete(key)
+          }
         }
 
-        if (ws.data !== key) {
-          session.subscribers.delete(key)
-          continue
-        }
-
-        try {
-          ws.send(chunk)
-        } catch {
-          session.subscribers.delete(key)
-        }
-      }
-
-      session.buffer += chunk
-      if (session.buffer.length <= BUFFER_LIMIT) return
-      const excess = session.buffer.length - BUFFER_LIMIT
-      session.buffer = session.buffer.slice(excess)
-      session.bufferCursor += excess
-    })
-    ptyProcess.onExit(({ exitCode }) => {
-      if (session.info.status === "exited") return
-      log.info("session exited", { id, exitCode })
-      session.info.status = "exited"
-      Bus.publish(Event.Exited, { id, exitCode })
-      remove(id)
-    })
+        session.buffer += chunk
+        if (session.buffer.length <= BUFFER_LIMIT) return
+        const excess = session.buffer.length - BUFFER_LIMIT
+        session.buffer = session.buffer.slice(excess)
+        session.bufferCursor += excess
+      }),
+    )
+    ptyProcess.onExit(
+      Instance.bind(({ exitCode }) => {
+        if (session.info.status === "exited") return
+        log.info("session exited", { id, exitCode })
+        session.info.status = "exited"
+        Bus.publish(Event.Exited, { id, exitCode })
+        remove(id)
+      }),
+    )
     Bus.publish(Event.Created, { info })
     return info
   }