forgot a file

utils/innertube-pool.ts

@@ -0,0 +1,111 @@
+import { Innertube } from 'youtubei.js'
+
+interface InnertubePoolSlot {
+  client: Promise<Innertube>
+  busy?: boolean
+}
+
+export interface InnertubeLease {
+  innertube: Innertube
+  refresh: () => Promise<Innertube>
+  release: () => void
+}
+
+export function createInnertubePool(size = 4) {
+  const pool = Array.from({ length: Math.max(1, size) }, () => ({
+    client: Innertube.create()
+  })) as InnertubePoolSlot[]
+  const waiters: Array<(lease: InnertubeLease) => void> = []
+
+  function getSlot(index: number) {
+    const slot = pool[index]
+
+    if (!slot) {
+      throw new Error(`Innertube slot ${index} not found`)
+    }
+
+    return slot
+  }
+
+  async function load(index: number) {
+    const slot = getSlot(index)
+
+    try {
+      return await slot.client
+    } catch {
+      slot.client = Innertube.create()
+      return await slot.client
+    }
+  }
+
+  async function refresh(index: number) {
+    const slot = getSlot(index)
+
+    slot.client = Innertube.create()
+    return await slot.client
+  }
+
+  function release(index: number) {
+    const next = waiters.shift()
+
+    if (next) {
+      void load(index).then((innertube) => next(createLease(index, innertube)))
+      return
+    }
+
+    delete getSlot(index).busy
+  }
+
+  function createLease(index: number, innertube: Innertube): InnertubeLease {
+    const lease: InnertubeLease = {
+      innertube,
+      refresh: async () => {
+        lease.innertube = await refresh(index)
+        return lease.innertube
+      },
+      release: () => release(index)
+    }
+
+    return lease
+  }
+
+  async function acquire() {
+    const index = pool.findIndex((slot) => !slot.busy)
+
+    if (index === -1) {
+      return await new Promise<InnertubeLease>((resolve) => {
+        waiters.push(resolve)
+      })
+    }
+
+    getSlot(index).busy = true
+    return createLease(index, await load(index))
+  }
+
+  async function use<T>(callback: (innertube: Innertube) => Promise<T>, retries = 5) {
+    const lease = await acquire()
+
+    try {
+      for (let attempt = 0; attempt < retries; attempt++) {
+        try {
+          return await callback(lease.innertube)
+        } catch (error) {
+          if (attempt === retries - 1) {
+            throw error
+          }
+
+          await lease.refresh()
+        }
+      }
+
+      throw new Error('Innertube retries exhausted')
+    } finally {
+      lease.release()
+    }
+  }
+
+  return {
+    acquire,
+    use
+  }
+}