dsh 0.2.0-rc.2: in-container update (experimental channel), path-agnostic compose, upstream patches adapted to 0.1.x/0.2.x

upstream/container/control-plane/modules/updater/lib/scheduler.mjs

@@ -0,0 +1,55 @@
+export class UpdateScheduler {
+  constructor({
+    check,
+    intervalSeconds = 21_600,
+    onError = async () => {},
+    random = Math.random,
+    setTimer = setTimeout,
+    clearTimer = clearTimeout,
+  }) {
+    if (!Number.isSafeInteger(intervalSeconds) || intervalSeconds < 60) throw new Error('update interval must be at least 60 seconds')
+    this.check = check
+    this.onError = onError
+    this.intervalMs = intervalSeconds * 1_000
+    this.random = random
+    this.setTimer = setTimer
+    this.clearTimer = clearTimer
+    this.timer = undefined
+    this.enabled = false
+  }
+
+  schedule() {
+    const jitter = 0.9 + this.random() * 0.2
+    const timer = this.setTimer(async () => {
+      if (this.timer !== timer) return
+      this.timer = undefined
+      try {
+        await this.check()
+      } catch (error) {
+        await Promise.resolve().then(() => this.onError(error)).catch(() => {})
+      }
+      if (this.enabled && this.timer === undefined) this.schedule()
+    }, Math.round(this.intervalMs * jitter))
+    this.timer = timer
+    timer.unref?.()
+  }
+
+  start() {
+    this.enabled = true
+    if (this.timer === undefined) this.schedule()
+  }
+
+  configure({ enabled, intervalSeconds }) {
+    if (typeof enabled !== 'boolean') throw new Error('automatic check enabled must be boolean')
+    if (!Number.isSafeInteger(intervalSeconds) || intervalSeconds < 60) throw new Error('update interval must be at least 60 seconds')
+    this.stop()
+    this.intervalMs = intervalSeconds * 1_000
+    if (enabled) this.start()
+  }
+
+  stop() {
+    this.enabled = false
+    if (this.timer !== undefined) this.clearTimer(this.timer)
+    this.timer = undefined
+  }
+}