replace queue with worker

packages/lib/Queue.ts

@@ -1,57 +0,0 @@
-export class Queue {
-  timeout?: number
-  messages: any[] = []
-
-  clear() {
-    this.messages = []
-  }
-
-  push(message: any) {
-    this.messages.push(message)
-    this.enqueueWork()
-  }
-
-  handle(message: any) {
-    throw new Error("Not implemented")
-  }
-
-  shouldSend(message: any) {
-    return true
-  }
-
-  doWork() {
-    for (let i = 0; i < 10; i++) {
-      if (this.messages.length === 0) {
-        break
-      }
-
-      // Pop the messages one at a time so handle can modify the queue
-      const [message] = this.messages.splice(0, 1)
-
-      if (this.shouldSend(message)) {
-        this.handle(message)
-      } else {
-        this.messages.push(message)
-      }
-    }
-
-    this.timeout = undefined
-    this.enqueueWork()
-  }
-
-  enqueueWork() {
-    if (this.timeout) {
-      return
-    }
-
-    if (this.messages.length === 0) {
-      return
-    }
-
-    this.timeout = setTimeout(() => this.doWork(), 100)
-  }
-
-  stop() {
-    clearTimeout(this.timeout)
-  }
-}

packages/lib/Worker.ts

@@ -0,0 +1,71 @@
+const ANY = Symbol("worker/ANY")
+
+export type WorkerOpts<T> = {
+  getKey?: (x: T) => any
+  shouldDefer?: (x: T) => boolean
+}
+
+export class Worker<T> {
+  buffer: T[] = []
+  handlers: Map<any, Array<(x: T) => void>> = new Map()
+  timeout: number | undefined
+
+  constructor(readonly opts: WorkerOpts<T> = {}) {}
+
+  #doWork = async () => {
+    for (let i = 0; i < 50; i++) {
+      if (this.buffer.length === 0) {
+        break
+      }
+
+      // Pop the buffer one at a time so handle can modify the queue
+      const [message] = this.buffer.splice(0, 1)
+
+      if (this.opts.shouldDefer?.(message)) {
+        this.buffer.push(message)
+      } else {
+        for (const handler of this.handlers.get(ANY) || []) {
+          await handler(message)
+        }
+
+        if (this.opts.getKey) {
+          const k = this.opts.getKey(message)
+
+          for (const handler of this.handlers.get(k) || []) {
+            await handler(message)
+          }
+        }
+      }
+    }
+
+    this.timeout = undefined
+    this.#enqueueWork()
+  }
+
+  #enqueueWork = () => {
+    if (!this.timeout && this.buffer.length > 0) {
+      this.timeout = setTimeout(this.#doWork, 50)
+    }
+  }
+
+  push = (message: T) => {
+    this.buffer.push(message)
+    this.#enqueueWork()
+  }
+
+  addHandler = (k: any, handler: (message: T) => void) => {
+    this.handlers.set(k, (this.handlers.get(k) || []).concat(handler))
+  }
+
+  addGlobalHandler = (handler: (message: T) => void) => {
+    this.addHandler(ANY, handler)
+  }
+
+  clear() {
+    this.buffer = []
+  }
+
+  stop() {
+    clearTimeout(this.timeout)
+  }
+}

packages/lib/index.ts

@@ -3,6 +3,6 @@ export * from './Deferred'
 export * from './Emitter'
 export * from './Fluent'
 export * from './LRUCache'
-export * from './Queue'
+export * from './Worker'
 export * from './Tools'
 export {default as normalizeUrl} from './normalize-url'