Resolve session resumption corner cases

Fix don't replace the startup promise when it has not been resolved
Fix clear caches and reset initialisation steps properly when not resuming after the handshake
Fix cases where a callback has been called twice after initialisation steps completed

src/controllers/status.ts

@@ -251,7 +251,7 @@ export class StatusController {
      * Attempt to reconnect an iOS device after a connection loss.
      */
     private reconnectIos(): void {
-        this.$log.warn(this.logTag, 'Connection lost (iOS). Attempting to reconnect...');
+        this.$log.info(this.logTag, 'Connection lost (iOS). Attempting to reconnect...');
 
         // Get original keys
         const originalKeyStore = this.webClientService.salty.keyStore;

src/services/webclient.ts

@@ -175,7 +175,7 @@ export class WebClientService {
     // State handling
     private startupPromise: ng.IDeferred<{}> = null; // TODO: deferred type
     private startupDone: boolean = false;
-    private pendingInitializationStepRoutines: threema.InitializationStepRoutine[] = [];
+    private pendingInitializationStepRoutines: Set<threema.InitializationStepRoutine> = new Set();
     private initialized: Set<threema.InitializationStep> = new Set();
     private stateService: StateService;
     private lastPush: Date = null;
@@ -827,23 +827,37 @@ export class WebClientService {
         }
 
         // If we could not resume for whatever reason
-        const requiredInitializationSteps = [];
         if (!resumeSession || !sessionWasResumed) {
             // Note: We cannot reset the message sequence number here any more since
             //       it has already been used for the connectionInfo message.
             this.discardSession({ resetMessageSequenceNumber: false });
             this.$log.debug(this.logTag, 'Session discarded');
 
-            // Remove all pending promises
+            // Reset fields, blob cache & pending requests in case the session
+            // cannot be resumed
+            this.clearCache();
             this.requestPromises.clear();
 
-            // Set required initialisation steps
-            requiredInitializationSteps.push(
-                InitializationStep.ClientInfo,
-                InitializationStep.Conversations,
-                InitializationStep.Receivers,
-                InitializationStep.Profile,
-            );
+            // Set required initialisation steps if we have finished the
+            // previous connection
+            if (this.startupPromise !== null) {
+                const requiredInitializationSteps = [
+                    InitializationStep.ClientInfo,
+                    InitializationStep.Conversations,
+                    InitializationStep.Receivers,
+                    InitializationStep.Profile,
+                ];
+                this.runAfterInitializationSteps(requiredInitializationSteps, () => {
+                    this.stateService.updateConnectionBuildupState('done');
+                    this.startupPromise.resolve();
+                    this.startupPromise = null;
+                    this.startupDone = true;
+                    this._resetInitializationSteps();
+                });
+            }
+
+            // Request initial data
+            this._requestInitialData();
         } else {
             this.$log.debug(this.logTag, 'Session resumed');
         }
@@ -867,23 +881,6 @@ export class WebClientService {
             });
         }
 
-        // Resolve startup promise once initialization is done
-        if (this.startupPromise !== null) {
-            this.runAfterInitializationSteps(requiredInitializationSteps, () => {
-                this.stateService.updateConnectionBuildupState('done');
-                this.startupPromise.resolve();
-                this.startupPromise = null;
-                this.startupDone = true;
-                this._resetInitializationSteps();
-            });
-        }
-
-        // If we could not resume for whatever reason
-        if (!resumeSession || !sessionWasResumed) {
-            // Request initial data
-            this._requestInitialData();
-        }
-
         // Fetch current version
         // Delay it to prevent the dialog from being closed by the messenger constructor,
         // which closes all open dialogs.
@@ -1008,7 +1005,12 @@ export class WebClientService {
         this.$log.debug(this.logTag, 'Starting WebClientService...');
 
         // Promise to track startup state
-        this.startupPromise = this.$q.defer();
+        if (this.startupPromise !== null) {
+            this.$log.debug(this.logTag, 'Reusing startup promise (was not resolved)');
+        } else {
+            this.$log.debug(this.logTag, 'Creating new startup promise');
+            this.startupPromise = this.$q.defer();
+        }
         this.startupDone = false;
 
         // Connect
@@ -1209,20 +1211,21 @@ export class WebClientService {
         this.initialized.add(name);
 
         // Check pending routines
-        this.pendingInitializationStepRoutines = this.pendingInitializationStepRoutines.filter((routine) => {
-            let isValid = true;
-            for (const requiredStep of routine.requiredSteps) {
-                if (!this.initialized.has(requiredStep)) {
-                    isValid = false;
-                    break;
-                }
-            }
-            if (isValid) {
+        for (const routine of this.pendingInitializationStepRoutines) {
+            const ready = routine.requiredSteps.every((requiredStep) => {
+                return this.initialized.has(requiredStep);
+            });
+
+            if (ready) {
                 this.$log.debug(this.logTag, 'Running routine after initialization "' + name + '" completed');
+
+                // Important: Remove the routine BEFORE calling it to prevent
+                //            it from being called more than once (due to nested
+                //            calls to .registerInitializationStep).
+                this.pendingInitializationStepRoutines.delete(routine);
                 routine.callback();
             }
-            return !isValid;
-        });
+        }
     }
 
     public setReceiverListener(listener: threema.ReceiverListener): void {
@@ -1981,7 +1984,7 @@ export class WebClientService {
     private _resetInitializationSteps(): void {
         this.$log.debug(this.logTag, 'Reset initialization steps');
         this.initialized.clear();
-        this.pendingInitializationStepRoutines = [];
+        this.pendingInitializationStepRoutines = new Set();
     }
 
     /**
@@ -3743,7 +3746,7 @@ export class WebClientService {
             if (!this.initialized.has(requiredStep)) {
                 this.$log.debug(this.logTag,
                     'Required initialization step', requiredStep, 'not completed, add pending routine');
-                this.pendingInitializationStepRoutines.push({
+                this.pendingInitializationStepRoutines.add({
                     requiredSteps: requiredSteps,
                     callback: callback,
                 } as threema.InitializationStepRoutine);