From ba002f96492fd311cb0396262b4f77c2edb6f8f5 Mon Sep 17 00:00:00 2001
From: Sam Rose <hello@samwho.dev>
Date: Fri, 2 Feb 2024 09:30:33 +0000
Subject: [PATCH] Clean up isolates when a request is finished.

---
 packages/backend-core/src/context/types.ts |  1 +
 packages/server/src/jsRunner/index.ts      |  8 ++++++++
 packages/server/src/middleware/cleanup.ts  | 16 ++++++++++++++++
 3 files changed, 25 insertions(+)
 create mode 100644 packages/server/src/middleware/cleanup.ts

diff --git a/packages/backend-core/src/context/types.ts b/packages/backend-core/src/context/types.ts
index cc052ca505..dad1af3bf8 100644
--- a/packages/backend-core/src/context/types.ts
+++ b/packages/backend-core/src/context/types.ts
@@ -15,4 +15,5 @@ export type ContextMap = {
     jsContext: Context
     helpersModule: Module
   }
+  cleanup?: (() => void | Promise<void>)[]
 }
diff --git a/packages/server/src/jsRunner/index.ts b/packages/server/src/jsRunner/index.ts
index 8e529d533d..9441a74d07 100644
--- a/packages/server/src/jsRunner/index.ts
+++ b/packages/server/src/jsRunner/index.ts
@@ -115,6 +115,14 @@ export function init() {
           }
 
           bbCtx.isolateRefs = { jsContext, jsIsolate, helpersModule }
+          if (!bbCtx.cleanup) {
+            bbCtx.cleanup = []
+          }
+          bbCtx.cleanup.push(() => {
+            helpersModule.release()
+            jsContext.release()
+            jsIsolate.dispose()
+          })
         }
 
         let { jsIsolate, jsContext, helpersModule } = bbCtx.isolateRefs!
diff --git a/packages/server/src/middleware/cleanup.ts b/packages/server/src/middleware/cleanup.ts
new file mode 100644
index 0000000000..5204d5cfb1
--- /dev/null
+++ b/packages/server/src/middleware/cleanup.ts
@@ -0,0 +1,16 @@
+import { Ctx } from "@budibase/types"
+import { context } from "@budibase/backend-core"
+
+export default async (ctx: Ctx, next: any) => {
+  const resp = next()
+
+  const current = context.getCurrentContext()
+  if (current?.cleanup) {
+    for (let fn of current.cleanup || []) {
+      await fn()
+    }
+    delete current.cleanup
+  }
+
+  return resp
+}