[Feature] Better Error Logging

.changeset/strong-moose-applaud.md

@@ -0,0 +1,6 @@
+---
+'@journeyapps/powersync-sdk-react-native': patch
+'@journeyapps/powersync-sdk-common': patch
+---
+
+Added better logging of streaming errors. Added warnings if Polyfills are not correctly configured.

packages/powersync-sdk-common/src/client/sync/stream/AbstractRemote.ts

@@ -1,23 +1,26 @@
+import Logger, { ILogger } from 'js-logger';
 import { PowerSyncCredentials } from '../../connection/PowerSyncCredentials';
 
-export type RemoteOptions = {
+export type RemoteConnector = {
   fetchCredentials: () => Promise<PowerSyncCredentials>;
 };
 
 //Refresh at least 30 sec before it expires
 const REFRESH_CREDENTIALS_SAFETY_PERIOD_MS = 30_000;
 
+export const DEFAULT_REMOTE_LOGGER = Logger.get('PowerSyncRemote');
+
 export abstract class AbstractRemote {
   protected credentials?: PowerSyncCredentials;
 
-  constructor(protected options: RemoteOptions) {}
+  constructor(protected connector: RemoteConnector, protected logger: ILogger = DEFAULT_REMOTE_LOGGER) {}
 
   async getCredentials(): Promise<PowerSyncCredentials> {
     const { expiresAt } = this.credentials ?? {};
     if (expiresAt && expiresAt > new Date(new Date().valueOf() + REFRESH_CREDENTIALS_SAFETY_PERIOD_MS)) {
       return this.credentials!;
     }
-    this.credentials = await this.options.fetchCredentials();
+    this.credentials = await this.connector.fetchCredentials();
     return this.credentials;
   }
 

packages/powersync-sdk-common/src/client/sync/stream/AbstractStreamingSyncImplementation.ts

@@ -123,6 +123,7 @@ export abstract class AbstractStreamingSyncImplementation extends BaseObserver<S
         await this.streamingSyncIteration(signal);
         // Continue immediately
       } catch (ex) {
+        this.logger.error(ex);
         this.updateSyncStatus(false);
         // On error, wait a little before retrying
         await new Promise((resolve) => setTimeout(resolve, this.options.retryDelayMs));

packages/powersync-sdk-react-native/README.md

@@ -491,6 +491,15 @@ export const TodoListDisplay = () => {
 }
 ```
 
+### Logging
+The default logger uses js-logger. Debug logs can be displayed with:
+
+```JavaScript
+import Logger from 'js-logger';
+Logger.useDefaults();
+Logger.setLevel(Logger.DEBUG);
+```
+
 
 # Known Issues
 

packages/powersync-sdk-react-native/package.json

@@ -27,6 +27,7 @@
     "@journeyapps/react-native-quick-sqlite": "0.0.2",
     "base-64": "^1.0.0",
     "react": "*",
+    "react-native": "*",
     "react-native-fetch-api": "^3.0.0",
     "react-native-get-random-values": "^1.9.0",
     "react-native-polyfill-globals": "^3.1.0",
@@ -42,6 +43,7 @@
   "devDependencies": {
     "@journeyapps/react-native-quick-sqlite": "0.0.2",
     "@types/async-lock": "^1.4.0",
+    "react-native": "0.72.4",
     "react": "18.2.0",
     "typescript": "^4.1.3"
   },

packages/powersync-sdk-react-native/src/sync/stream/ReactNativeRemote.ts

@@ -1,4 +1,7 @@
 import { AbstractRemote } from '@journeyapps/powersync-sdk-common';
+import { Platform } from 'react-native';
+
+export const STREAMING_POST_TIMEOUT_MS = 30_000;
 
 export class ReactNativeRemote extends AbstractRemote {
   async post(path: string, data: any, headers: Record<string, string> = {}): Promise<any> {
@@ -43,8 +46,30 @@ export class ReactNativeRemote extends AbstractRemote {
     headers: Record<string, string> = {},
     signal?: AbortSignal
   ): Promise<any> {
+    // Ensure polyfills are present
+    if (
+      typeof ReadableStream == 'undefined' ||
+      typeof TextEncoder == 'undefined' ||
+      typeof TextDecoder == 'undefined'
+    ) {
+      const errorMessage = `Polyfills are undefined. Please ensure React Native polyfills are installed and imported in the app entrypoint.
+      "import 'react-native-polyfill-globals/auto';"
+      `;
+      this.logger.error(errorMessage);
+      throw new Error(errorMessage);
+    }
+
     const credentials = await this.getCredentials();
 
+    let timeout =
+      Platform.OS == 'android'
+        ? setTimeout(() => {
+            this.logger.warn(
+              `HTTP Streaming POST is taking longer than 30 seconds to resolve. If using a debug build, please ensure Flipper Network plugin is disabled.`
+            );
+          }, STREAMING_POST_TIMEOUT_MS)
+        : null;
+
     const res = await fetch(credentials.endpoint + path, {
       method: 'POST',
       headers: { ...headers, ...(await this.getHeaders()) },
@@ -63,9 +88,11 @@ export class ReactNativeRemote extends AbstractRemote {
       throw ex;
     });
 
+    clearTimeout(timeout);
+
     if (!res.ok) {
       const text = await res.text();
-      console.error(`Could not POST streaming to ${path} - ${res.status} - ${res.statusText}: ${text}`);
+      this.logger.error(`Could not POST streaming to ${path} - ${res.status} - ${res.statusText}: ${text}`);
       const error: any = new Error(`HTTP ${res.statusText}: ${text}`);
       error.status = res.status;
       throw error;