add export logs button when session fails to load

src/domain/SessionLoadViewModel.js

@@ -102,8 +102,7 @@ export class SessionLoadViewModel extends ViewModel {
 
     get loadLabel() {
         const sc = this._sessionContainer;
-        const error = this._error || (sc && sc.loadError);
-
+        const error = this._getError();
         if (error || (sc && sc.loadStatus.get() === LoadStatus.Error)) {
             return `Something went wrong: ${error && error.message}.`;
         }
@@ -124,4 +123,17 @@ export class SessionLoadViewModel extends ViewModel {
 
         return `Preparing…`;
     }
+
+    _getError() {
+        return this._error || this._sessionContainer?.loadError; 
+    }
+
+    get hasError() {
+        return !!this._getError();
+    }
+
+    async exportLogs() {
+        const logExport = await this.logger.export();
+        this.platform.saveFileAs(logExport.asBlob(), `hydrogen-logs-${this.platform.clock.now()}.json`);
+    }
 }

src/platform/web/ui/login/SessionLoadStatusView.js

@@ -22,9 +22,14 @@ to show the current state of loading the session.
 Just a spinner and a label, meant to be used as a paragraph */
 export class SessionLoadStatusView extends TemplateView {
     render(t) {
+        const exportLogsButtonIfFailed = t.if(vm => vm.hasError, (t, vm) => {
+            return t.button({
+                onClick: () => vm.exportLogs()
+            }, vm.i18n`Export logs`);
+        });
         return t.div({className: "SessionLoadStatusView"}, [
             spinner(t, {hiddenWithLayout: vm => !vm.loading}),
-            t.p(vm => vm.loadLabel)
+            t.p([vm => vm.loadLabel, exportLogsButtonIfFailed])
         ]);
     }
 }