prepare 4.0.3 release (#62)

Author: LaunchDarklyReleaseBot

src/__tests__/LDClient-streaming-test.js

@@ -1,3 +1,4 @@
+import * as messages from '../messages';
 import * as utils from '../utils';
 
 import { AsyncQueue, eventSink, sleepAsync, withCloseable } from 'launchdarkly-js-test-helpers';
@@ -650,6 +651,38 @@ describe('LDClient streaming', () => {
       });
     });
 
+    describe('emits error if malformed JSON is received', () => {
+      const doMalformedJsonEventTest = async (eventName, eventData) => {
+        // First, verify that there isn't an unhandled rejection if we're not listening for an error
+        await withClientAndServer({}, async client => {
+          await client.waitForInitialization();
+          client.setStreaming(true);
+
+          const stream = await expectStreamConnecting(fullStreamUrlWithUser);
+          stream.eventSource.mockEmit(eventName, { data: eventData });
+        });
+
+        // Then, repeat the test using a listener to observe the error event
+        await withClientAndServer({}, async client => {
+          const errorEvents = new AsyncQueue();
+          client.on('error', e => errorEvents.add(e));
+
+          await client.waitForInitialization();
+          client.setStreaming(true);
+
+          const stream = await expectStreamConnecting(fullStreamUrlWithUser);
+          stream.eventSource.mockEmit(eventName, { data: eventData });
+
+          const e = await errorEvents.take();
+          expect(e.message).toEqual(messages.invalidData());
+        });
+      };
+
+      it('in put event', async () => doMalformedJsonEventTest('put', '{no'));
+      it('in patch event', async () => doMalformedJsonEventTest('patch', '{no'));
+      it('in delete event', async () => doMalformedJsonEventTest('delete', '{no'));
+    });
+
     it('reconnects to stream if the user changes', async () => {
       const user2 = { key: 'user2' };
       const encodedUser2 = 'eyJrZXkiOiJ1c2VyMiJ9';

src/errors.js

@@ -18,6 +18,7 @@ const LDInvalidUserError = createCustomError('LaunchDarklyInvalidUserError');
 const LDInvalidEventKeyError = createCustomError('LaunchDarklyInvalidEventKeyError');
 const LDInvalidArgumentError = createCustomError('LaunchDarklyInvalidArgumentError');
 const LDFlagFetchError = createCustomError('LaunchDarklyFlagFetchError');
+const LDInvalidDataError = createCustomError('LaunchDarklyInvalidDataError');
 
 function isHttpErrorRecoverable(status) {
   if (status >= 400 && status < 500) {
@@ -32,6 +33,7 @@ module.exports = {
   LDInvalidUserError,
   LDInvalidEventKeyError,
   LDInvalidArgumentError,
+  LDInvalidDataError,
   LDFlagFetchError,
   isHttpErrorRecoverable,
 };

src/index.js

@@ -386,6 +386,14 @@ function initialize(env, user, specifiedOptions, platform, extraOptionDefs) {
     if (!ident.getUser()) {
       return;
     }
+    const tryParseData = jsonData => {
+      try {
+        return JSON.parse(jsonData);
+      } catch (err) {
+        emitter.maybeReportError(new errors.LDInvalidDataError(messages.invalidData()));
+        return undefined;
+      }
+    };
     stream.connect(ident.getUser(), hash, {
       ping: function() {
         logger.debug(messages.debugStreamPing());
@@ -404,12 +412,20 @@ function initialize(env, user, specifiedOptions, platform, extraOptionDefs) {
           });
       },
       put: function(e) {
-        const data = JSON.parse(e.data);
+        const data = tryParseData(e.data);
+        if (!data) {
+          return;
+        }
         logger.debug(messages.debugStreamPut());
-        replaceAllFlags(data); // don't wait for this Promise to be resolved
+        replaceAllFlags(data);
+        // Don't wait for this Promise to be resolved; note that replaceAllFlags is guaranteed
+        // never to have an unhandled rejection
       },
       patch: function(e) {
-        const data = JSON.parse(e.data);
+        const data = tryParseData(e.data);
+        if (!data) {
+          return;
+        }
         // If both the flag and the patch have a version property, then the patch version must be
         // greater than the flag version for us to accept the patch.  If either one has no version
         // then the patch always succeeds.
@@ -432,7 +448,10 @@ function initialize(env, user, specifiedOptions, platform, extraOptionDefs) {
         }
       },
       delete: function(e) {
-        const data = JSON.parse(e.data);
+        const data = tryParseData(e.data);
+        if (!data) {
+          return;
+        }
         if (!flags[data.key] || flags[data.key].version < data.version) {
           logger.debug(messages.debugStreamDelete(data.key));
           const mods = {};

src/messages.js

@@ -68,6 +68,10 @@ const invalidUser = function() {
   return 'Invalid user specified.' + docLink;
 };
 
+const invalidData = function() {
+  return 'Invalid data received from LaunchDarkly; connection may have been interrupted';
+};
+
 const bootstrapOldFormat = function() {
   return (
     'LaunchDarkly client was initialized with bootstrap data that did not include flag metadata. ' +
@@ -201,6 +205,7 @@ module.exports = {
   httpUnavailable,
   identifyDisabled,
   invalidContentType,
+  invalidData,
   invalidKey,
   invalidUser,
   localStorageUnavailable,