Add error callback for database .on handler (matches Web spec)

Author: chrisbianca

android/src/main/java/io/fullstack/firestack/database/FirestackDatabaseReference.java

@@ -68,7 +68,7 @@ public void onChildMoved(DataSnapshot dataSnapshot, String previousChildName) {
 
         @Override
         public void onCancelled(DatabaseError error) {
-          handleDatabaseError(eventName, error);
+          handleDatabaseError(error);
         }
       };
       mQuery.addChildEventListener(mEventListener);
@@ -90,7 +90,7 @@ public void onDataChange(DataSnapshot dataSnapshot) {
 
         @Override
         public void onCancelled(DatabaseError error) {
-          handleDatabaseError("value", error);
+          handleDatabaseError(error);
         }
       };
       mQuery.addValueEventListener(mValueListener);
@@ -162,22 +162,22 @@ private void handleDatabaseEvent(final String name, final DataSnapshot dataSnaps
     WritableMap data = Utils.dataSnapshotToMap(name, mPath, mModifiersString, dataSnapshot);
     WritableMap evt = Arguments.createMap();
     evt.putString("eventName", name);
-    evt.putString("path", mPath);
-    evt.putString("modifiersString", mModifiersString);
     evt.putMap("body", data);
 
     Utils.sendEvent(mReactContext, "database_event", evt);
   }
 
-  private void handleDatabaseError(final String name, final DatabaseError error) {
+  private void handleDatabaseError(final DatabaseError error) {
     WritableMap err = Arguments.createMap();
+    err.putString("eventName", "database_error");
+    err.putString("path", mPath);
+    err.putString("modifiersString", mModifiersString);
     err.putInt("errorCode", error.getCode());
     err.putString("errorDetails", error.getDetails());
-    err.putString("description", error.getMessage());
+    err.putString("msg", error.getMessage());
 
     WritableMap evt  = Arguments.createMap();
-    evt.putString("eventName", name);
-    evt.putString("path", mPath);
+    evt.putString("eventName", "database_error");
     evt.putMap("body", err);
 
     Utils.sendEvent(mReactContext, "database_error", evt);

ios/Firestack/FirestackDatabase.m

@@ -58,7 +58,9 @@ - (void) addEventHandler:(NSString *) eventName
         };
         id errorBlock = ^(NSError * _Nonnull error) {
             NSLog(@"Error onDBEvent: %@", [error debugDescription]);
-            [self getAndSendDatabaseError:error withPath: _path];
+            [self getAndSendDatabaseError:error
+                                     path:_path
+                          modifiersString:_modifiersString];
         };
         int eventType = [self eventTypeFromName:eventName];
         FIRDatabaseHandle handle = [_query observeEventType:eventType
@@ -158,11 +160,13 @@ - (NSDictionary *) snapshotToDict:(FIRDataSnapshot *) snapshot
 }
 
 - (NSDictionary *) getAndSendDatabaseError:(NSError *) error
-                                  withPath:(NSString *) path
+                                      path:(NSString *) path
+                           modifiersString:(NSString *) modifiersString
 {
     NSDictionary *evt = @{
                           @"eventName": DATABASE_ERROR_EVENT,
                           @"path": path,
+                          @"modifiersString": modifiersString,
                           @"msg": [error debugDescription]
                           };
     [self sendJSEvent:DATABASE_ERROR_EVENT title:DATABASE_ERROR_EVENT props: evt];

lib/modules/database/index.js

@@ -19,6 +19,7 @@ export default class Database extends Base {
   constructor(firestack: Object, options: Object = {}) {
     super(firestack, options);
     this.subscriptions = {};
+    this.errorSubscriptions = {};
     this.serverTimeOffset = 0;
     this.persistenceEnabled = false;
     this.namespace = 'firestack:database';
@@ -86,13 +87,17 @@ export default class Database extends Base {
    * @param cb
    * @returns {*}
    */
-  on(path: string, modifiersString: string, modifiers: Array<string>, eventName: string, cb: () => void) {
+  on(path: string, modifiersString: string, modifiers: Array<string>, eventName: string, cb: () => void, errorCb: () => void) {
     const handle = this._handle(path, modifiersString);
     this.log.debug('adding on listener', handle);
 
     if (!this.subscriptions[handle]) this.subscriptions[handle] = {};
     if (!this.subscriptions[handle][eventName]) this.subscriptions[handle][eventName] = [];
     this.subscriptions[handle][eventName].push(cb);
+    if (errorCb) {
+        if (!this.errorSubscriptions[handle]) this.errorSubscriptions[handle] = [];
+        this.errorSubscriptions[handle].push(errorCb);
+    }
 
     return promisify('on', FirestackDatabase)(path, modifiersString, modifiers, eventName);
   }
@@ -129,7 +134,7 @@ export default class Database extends Base {
     } else {
       this.subscriptions[handle] = {};
     }
-
+    this.errorSubscriptions[handle] = [];
     return promisify('off', FirestackDatabase)(path, modifiersString, eventName);
   }
 
@@ -207,6 +212,12 @@ export default class Database extends Base {
    * @private
    */
   _handleDatabaseError(err: Object) {
-    this.log.debug('_handleDatabaseError ->', err);
+    const body = err.body || {};
+    const { path, modifiersString, eventName, msg } = body;
+    const handle = this._handle(path, modifiersString);
+
+    this.log.debug('_handleDatabaseError ->', handle, eventName, err);
+
+    if (this.errorSubscriptions[handle]) this.errorSubscriptions[handle].forEach((cb) => cb(new Error(msg)));
   }
 }

lib/modules/database/reference.js

@@ -94,13 +94,14 @@ export default class Reference extends ReferenceBase {
       });
   }
 
-  on(eventName: string, cb: () => any) {
+  on(eventName: string, cb: () => any, errorCb: () => any) {
     if (!isFunction(cb)) throw new Error('The specified callback must be a function');
+    if (errorCb && !isFunction(errorCb)) throw new Error('The specified error callback must be a function');
     const path = this._dbPath();
     const modifiers = this.query.getModifiers();
     const modifiersString = this.query.getModifiersString();
     this.log.debug('adding reference.on', path, modifiersString, eventName);
-    return this.db.on(path, modifiersString, modifiers, eventName, cb);
+    return this.db.on(path, modifiersString, modifiers, eventName, cb, errorCb);
   }
 
   once(eventName: string = 'once', cb: (snapshot: Object) => void) {