feat(shared): add Effect-idiomatic file lock (EffectFlock) (#22681)

1 files changed, 64 insertions, 0 deletions

diff --git a/packages/shared/test/fixture/effect-flock-worker.ts b/packages/shared/test/fixture/effect-flock-worker.ts
new file mode 100644
index 000000000..7fd2e144a
--- /dev/null
+++ b/packages/shared/test/fixture/effect-flock-worker.ts
@@ -0,0 +1,64 @@
+import fs from "fs/promises"
+import path from "path"
+import os from "os"
+import { Effect, Layer } from "effect"
+import { AppFileSystem } from "@opencode-ai/shared/filesystem"
+import { EffectFlock } from "@opencode-ai/shared/util/effect-flock"
+import { Global } from "@opencode-ai/shared/global"
+
+type Msg = {
+  key: string
+  dir: string
+  holdMs?: number
+  ready?: string
+  active?: string
+  done?: string
+}
+
+function sleep(ms: number) {
+  return new Promise<void>((resolve) => setTimeout(resolve, ms))
+}
+
+const msg: Msg = JSON.parse(process.argv[2]!)
+
+const testGlobal = Layer.succeed(
+  Global.Service,
+  Global.Service.of({
+    home: os.homedir(),
+    data: os.tmpdir(),
+    cache: os.tmpdir(),
+    config: os.tmpdir(),
+    state: os.tmpdir(),
+    bin: os.tmpdir(),
+    log: os.tmpdir(),
+  }),
+)
+
+const testLayer = EffectFlock.layer.pipe(Layer.provide(testGlobal), Layer.provide(AppFileSystem.defaultLayer))
+
+async function job() {
+  if (msg.ready) await fs.writeFile(msg.ready, String(process.pid))
+  if (msg.active) await fs.writeFile(msg.active, String(process.pid), { flag: "wx" })
+
+  try {
+    if (msg.holdMs && msg.holdMs > 0) await sleep(msg.holdMs)
+    if (msg.done) await fs.appendFile(msg.done, "1\n")
+  } finally {
+    if (msg.active) await fs.rm(msg.active, { force: true })
+  }
+}
+
+await Effect.runPromise(
+  Effect.gen(function* () {
+    const flock = yield* EffectFlock.Service
+    yield* flock.withLock(
+      Effect.promise(() => job()),
+      msg.key,
+      msg.dir,
+    )
+  }).pipe(Effect.provide(testLayer)),
+).catch((err) => {
+  const text = err instanceof Error ? (err.stack ?? err.message) : String(err)
+  process.stderr.write(text)
+  process.exit(1)
+})