WebSocket Timeout Fix

.changeset/bright-yaks-pump.md

@@ -0,0 +1,7 @@
+---
+'@powersync/common': patch
+'@powersync/react-native': patch
+'@powersync/web': patch
+---
+
+Fixed bug where a WebSocket connection timeout could cause an uncaught exception.

demos/react-supabase-todolist/src/app/views/layout.tsx

@@ -1,3 +1,6 @@
+import { LOGIN_ROUTE, SQL_CONSOLE_ROUTE, TODO_LISTS_ROUTE } from '@/app/router';
+import { useNavigationPanel } from '@/components/navigation/NavigationPanelContext';
+import { useSupabase } from '@/components/providers/SystemProvider';
 import ChecklistRtlIcon from '@mui/icons-material/ChecklistRtl';
 import ExitToAppIcon from '@mui/icons-material/ExitToApp';
 import MenuIcon from '@mui/icons-material/Menu';
@@ -17,16 +20,15 @@ import {
   ListItemButton,
   ListItemIcon,
   ListItemText,
+  Menu,
+  MenuItem,
   Toolbar,
   Typography,
   styled
 } from '@mui/material';
-import React from 'react';
 import { usePowerSync, useStatus } from '@powersync/react';
+import React from 'react';
 import { useNavigate } from 'react-router-dom';
-import { useSupabase } from '@/components/providers/SystemProvider';
-import { useNavigationPanel } from '@/components/navigation/NavigationPanelContext';
-import { LOGIN_ROUTE, SQL_CONSOLE_ROUTE, TODO_LISTS_ROUTE } from '@/app/router';
 
 export default function ViewsLayout({ children }: { children: React.ReactNode }) {
   const powerSync = usePowerSync();
@@ -37,6 +39,8 @@ export default function ViewsLayout({ children }: { children: React.ReactNode })
   const [openDrawer, setOpenDrawer] = React.useState(false);
   const { title } = useNavigationPanel();
 
+  const [connectionAnchor, setConnectionAnchor] = React.useState<null | HTMLElement>(null);
+
   const NAVIGATION_ITEMS = React.useMemo(
     () => [
       {
@@ -72,16 +76,47 @@ export default function ViewsLayout({ children }: { children: React.ReactNode })
             color="inherit"
             aria-label="menu"
             sx={{ mr: 2 }}
-            onClick={() => setOpenDrawer(!openDrawer)}
-          >
+            onClick={() => setOpenDrawer(!openDrawer)}>
             <MenuIcon />
           </IconButton>
           <Box sx={{ flexGrow: 1 }}>
             <Typography>{title}</Typography>
           </Box>
           <NorthIcon sx={{ marginRight: '-10px' }} color={status?.dataFlowStatus.uploading ? 'primary' : 'inherit'} />
           <SouthIcon color={status?.dataFlowStatus.downloading ? 'primary' : 'inherit'} />
-          {status?.connected ? <WifiIcon /> : <SignalWifiOffIcon />}
+          <Box
+            sx={{ cursor: 'pointer' }}
+            onClick={(event) => {
+              setConnectionAnchor(event.currentTarget);
+            }}>
+            {status?.connected ? <WifiIcon /> : <SignalWifiOffIcon />}
+            {/* Allows for manual connection and disconnect for testing purposes */}
+            <Menu
+              id="connection-menu"
+              anchorEl={connectionAnchor}
+              open={Boolean(connectionAnchor)}
+              onClose={() => setConnectionAnchor(null)}>
+              {status?.connected ? (
+                <MenuItem
+                  onClick={(event) => {
+                    event.stopPropagation();
+                    setConnectionAnchor(null);
+                    powerSync.disconnect();
+                  }}>
+                  Disconnect
+                </MenuItem>
+              ) : supabase ? (
+                <MenuItem
+                  onClick={(event) => {
+                    event.stopPropagation();
+                    setConnectionAnchor(null);
+                    powerSync.connect(supabase);
+                  }}>
+                  Connect
+                </MenuItem>
+              ) : null}
+            </Menu>
+          </Box>
         </Toolbar>
       </S.TopBar>
       <Drawer anchor={'left'} open={openDrawer} onClose={() => setOpenDrawer(false)}>
@@ -95,8 +130,7 @@ export default function ViewsLayout({ children }: { children: React.ReactNode })
                   await item.beforeNavigate?.();
                   navigate(item.path);
                   setOpenDrawer(false);
-                }}
-              >
+                }}>
                 <ListItemIcon>{item.icon()}</ListItemIcon>
                 <ListItemText primary={item.title} />
               </ListItemButton>

packages/common/src/client/sync/stream/AbstractRemote.ts

@@ -7,11 +7,7 @@ import PACKAGE from '../../../../package.json' with { type: 'json' };
 import { AbortOperation } from '../../../utils/AbortOperation.js';
 import { DataStream } from '../../../utils/DataStream.js';
 import { PowerSyncCredentials } from '../../connection/PowerSyncCredentials.js';
-import {
-  StreamingSyncLine,
-  StreamingSyncLineOrCrudUploadComplete,
-  StreamingSyncRequest
-} from './streaming-sync-types.js';
+import { StreamingSyncRequest } from './streaming-sync-types.js';
 import { WebsocketClientTransport } from './WebsocketClientTransport.js';
 
 export type BSONImplementation = typeof BSON;
@@ -305,6 +301,27 @@ export abstract class AbstractRemote {
     // automatically as a header.
     const userAgent = this.getUserAgent();
 
+    const stream = new DataStream<T, Uint8Array>({
+      logger: this.logger,
+      pressure: {
+        lowWaterMark: SYNC_QUEUE_REQUEST_LOW_WATER
+      },
+      mapLine: map
+    });
+
+    // Handle upstream abort
+    if (options.abortSignal?.aborted) {
+      throw new AbortOperation('Connection request aborted');
+    } else {
+      options.abortSignal?.addEventListener(
+        'abort',
+        () => {
+          stream.close();
+        },
+        { once: true }
+      );
+    }
+
     let keepAliveTimeout: any;
     const resetTimeout = () => {
       clearTimeout(keepAliveTimeout);
@@ -315,15 +332,28 @@ export abstract class AbstractRemote {
     };
     resetTimeout();
 
+    // Typescript complains about this being `never` if it's not assigned here.
+    // This is assigned in `wsCreator`.
+    let disposeSocketConnectionTimeout = () => {};
+
     const url = this.options.socketUrlTransformer(request.url);
     const connector = new RSocketConnector({
       transport: new WebsocketClientTransport({
         url,
         wsCreator: (url) => {
           const socket = this.createSocket(url);
+          disposeSocketConnectionTimeout = stream.registerListener({
+            closed: () => {
+              // Allow closing the underlying WebSocket if the stream was closed before the
+              // RSocket connect completed. This should effectively abort the request.
+              socket.close();
+            }
+          });
+
           socket.addEventListener('message', (event) => {
             resetTimeout();
           });
+
           return socket;
         }
       }),
@@ -345,22 +375,19 @@ export abstract class AbstractRemote {
     let rsocket: RSocket;
     try {
       rsocket = await connector.connect();
+      // The connection is established, we no longer need to monitor the initial timeout
+      disposeSocketConnectionTimeout();
     } catch (ex) {
       this.logger.error(`Failed to connect WebSocket`, ex);
       clearTimeout(keepAliveTimeout);
+      if (!stream.closed) {
+        await stream.close();
+      }
       throw ex;
     }
 
     resetTimeout();
 
-    const stream = new DataStream<T, Uint8Array>({
-      logger: this.logger,
-      pressure: {
-        lowWaterMark: SYNC_QUEUE_REQUEST_LOW_WATER
-      },
-      mapLine: map
-    });
-
     let socketIsClosed = false;
     const closeSocket = () => {
       clearTimeout(keepAliveTimeout);
@@ -455,18 +482,6 @@ export abstract class AbstractRemote {
       }
     });
 
-    /**
-     * Handle abort operations here.
-     * Unfortunately cannot insert them into the connection.
-     */
-    if (options.abortSignal?.aborted) {
-      stream.close();
-    } else {
-      options.abortSignal?.addEventListener('abort', () => {
-        stream.close();
-      });
-    }
-
     return stream;
   }