From 4f43f9fa542ca4442e99ffc55e1702e1ea32bda7 Mon Sep 17 00:00:00 2001
From: Ben Allfree <ben@benallfree.com>
Date: Sun, 18 Jun 2023 05:50:28 -0700
Subject: [PATCH] enh: cleanupManager async cleanups and singleton shutdown

---
 packages/common/src/CleanupManager.ts | 43 ++++++++++++++++++++++-----
 1 file changed, 36 insertions(+), 7 deletions(-)

diff --git a/packages/common/src/CleanupManager.ts b/packages/common/src/CleanupManager.ts
index 8cbf3a4f..5111b42c 100644
--- a/packages/common/src/CleanupManager.ts
+++ b/packages/common/src/CleanupManager.ts
@@ -1,20 +1,49 @@
-import { map } from '@s-libs/micro-dash'
+import { reduce, values } from '@s-libs/micro-dash'
+import { nanoid } from 'nanoid'
+import { logger } from './Logger'
 
-export type CleanupFunc = () => any
-export const createCleanupManager = () => {
+export type CleanupFunc = () => Promise<void> | void
+type CleanupRec = {
+  cleanup: CleanupFunc
+  priority: number
+}
+export const CLEANUP_DEFAULT_PRIORITY = 10
+
+export const createCleanupManager = (slug?: string) => {
+  const _slug = slug || nanoid()
+  const { error, warn, dbg } = logger().create(`cleanupManager:${_slug}`)
   let i = 0
-  const cleanups: any = {}
-  const add = (cb: CleanupFunc) => {
+  const cleanups: { [_: number]: CleanupRec } = {}
+  const add = (cb: CleanupFunc, priority = CLEANUP_DEFAULT_PRIORITY) => {
     const idx = i++
     const cleanup = async () => {
       await cb()
       delete cleanups[idx]
     }
-    cleanups[idx] = cleanup
+    cleanups[idx] = { cleanup, priority }
     return cleanup
   }
 
-  const shutdown = () => Promise.all(map(cleanups, (v) => v()))
+  let _shutdownP: Promise<void> | undefined = undefined
+  const shutdown: () => Promise<void> = () => {
+    if (_shutdownP) return _shutdownP
+    const _cleanupFuncs = values(cleanups)
+      .sort((a, b) => a.priority - b.priority)
+      .map((v) => v.cleanup)
+    _shutdownP = reduce(
+      _cleanupFuncs,
+      (c, v) => {
+        return c.then(() => v())
+      },
+      Promise.resolve()
+    ).catch((e) => {
+      error(
+        `Cleanup functions are failing. This should never happen, check all cleanup functions to make sure they are trapping their exceptions.`
+      )
+      throw e
+    })
+    return _shutdownP
+  }
 
   return { add, shutdown }
 }