From 6d8921978b7bc5f5c596d8666b49c0b198bfc930 Mon Sep 17 00:00:00 2001
From: mike12345567 <me@michaeldrury.co.uk>
Date: Tue, 24 Sep 2024 15:30:39 +0100
Subject: [PATCH] Quick temporary fix for issue - previously the invalid state
 was never reset, which can cause apps to go missing completely, updating this
 so it will fix it self after a short while.

---
 .../backend-core/src/cache/appMetadata.ts     |  6 ++---
 .../backend-core/src/db/couch/DatabaseImpl.ts | 25 +++++++++++++++----
 2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/packages/backend-core/src/cache/appMetadata.ts b/packages/backend-core/src/cache/appMetadata.ts
index d442511fb8..144836029f 100644
--- a/packages/backend-core/src/cache/appMetadata.ts
+++ b/packages/backend-core/src/cache/appMetadata.ts
@@ -11,6 +11,7 @@ export interface DeletedApp {
 }
 
 const EXPIRY_SECONDS = 3600
+const INVALID_EXPIRY_SECONDS = 60
 
 /**
  * The default populate app metadata function
@@ -48,9 +49,8 @@ export async function getAppMetadata(appId: string): Promise<App | DeletedApp> {
       // app DB left around, but no metadata, it is invalid
       if (err && err.status === 404) {
         metadata = { state: AppState.INVALID }
-        // don't expire the reference to an invalid app, it'll only be
-        // updated if a metadata doc actually gets stored (app is remade/reverted)
-        expiry = undefined
+        // expire invalid apps regularly, in-case it was only briefly invalid
+        expiry = INVALID_EXPIRY_SECONDS
       } else {
         throw err
       }
diff --git a/packages/backend-core/src/db/couch/DatabaseImpl.ts b/packages/backend-core/src/db/couch/DatabaseImpl.ts
index aa4656bf64..180cd22efa 100644
--- a/packages/backend-core/src/db/couch/DatabaseImpl.ts
+++ b/packages/backend-core/src/db/couch/DatabaseImpl.ts
@@ -43,6 +43,9 @@ function buildNano(couchInfo: { url: string; cookie: string }) {
 }
 
 type DBCall<T> = () => Promise<T>
+type DBCallback<T> = (
+  db: Nano.DocumentScope<any>
+) => Promise<DBCall<T>> | DBCall<T>
 
 class CouchDBError extends Error implements DBError {
   status: number
@@ -171,8 +174,8 @@ export class DatabaseImpl implements Database {
   }
 
   // this function fetches the DB and handles if DB creation is needed
-  private async performCall<T>(
-    call: (db: Nano.DocumentScope<any>) => Promise<DBCall<T>> | DBCall<T>
+  private async performCallWithDBCreation<T>(
+    call: DBCallback<T>
   ): Promise<any> {
     const db = this.getDb()
     const fnc = await call(db)
@@ -181,13 +184,24 @@ export class DatabaseImpl implements Database {
     } catch (err: any) {
       if (err.statusCode === 404 && err.reason === DATABASE_NOT_FOUND) {
         await this.checkAndCreateDb()
-        return await this.performCall(call)
+        return await this.performCallWithDBCreation(call)
       }
       // stripping the error down the props which are safe/useful, drop everything else
       throw new CouchDBError(`CouchDB error: ${err.message}`, err)
     }
   }
 
+  private async performCall<T>(call: DBCallback<T>): Promise<any> {
+    const db = this.getDb()
+    const fnc = await call(db)
+    try {
+      return await fnc()
+    } catch (err: any) {
+      // stripping the error down the props which are safe/useful, drop everything else
+      throw new CouchDBError(`CouchDB error: ${err.message}`, err)
+    }
+  }
+
   async get<T extends Document>(id?: string): Promise<T> {
     return this.performCall(db => {
       if (!id) {
@@ -227,6 +241,7 @@ export class DatabaseImpl implements Database {
   }
 
   async remove(idOrDoc: string | Document, rev?: string) {
+    // not a read call - but don't create a DB to delete a document
     return this.performCall(db => {
       let _id: string
       let _rev: string
@@ -286,7 +301,7 @@ export class DatabaseImpl implements Database {
     if (!document._id) {
       throw new Error("Cannot store document without _id field.")
     }
-    return this.performCall(async db => {
+    return this.performCallWithDBCreation(async db => {
       if (!document.createdAt) {
         document.createdAt = new Date().toISOString()
       }
@@ -309,7 +324,7 @@ export class DatabaseImpl implements Database {
 
   async bulkDocs(documents: AnyDocument[]) {
     const now = new Date().toISOString()
-    return this.performCall(db => {
+    return this.performCallWithDBCreation(db => {
       return () =>
         db.bulk({
           docs: documents.map(d => ({ createdAt: now, ...d, updatedAt: now })),