Firebase calls all fail with java.util.zip.ZipException: Not in GZIP format with apache httpclient 5.6 #1173

Activity

1. lahirumaramba

   assigned

   lahirumaramba

   and

   jonathanedey

   on Jan 29, 2026
2. lahirumaramba

   added the

   Bug

   issue type on Jan 29, 2026
3. lahirumaramba

   added

   api: messaging

   on Jan 29, 2026
4. marksulls commented on Feb 3, 2026

   

   marksulls

   on Feb 3, 2026

   Last edited by marksulls

   More actions

   I am getting the same issue. I copied the default HttpClient / HttpTransport configuration out of the ApiClientUtils.getDefaultTransport() method and then added disableContentCompression() to the HttpAsyncClientBuilder. This seems to fix the issue, although I only tested it on creating tenants.

   PoolingAsyncClientConnectionManager connectionManager =
                   PoolingAsyncClientConnectionManagerBuilder.create()
                           // Set Max total connections to match google api client limits
                           // https://github.com/googleapis/google-http-java-client/blob/f9d4e15bd3c784b1fd3b0f3468000a91c6f79715/google-http-client-apache-v5/src/main/java/com/google/api/client/http/apache/v5/Apache5HttpTransport.java#L151
                           .setMaxConnTotal(200)
                           // Set max connections per route to match the concurrent stream limit of the FCM backend.
                           .setMaxConnPerRoute(100)
                           .setDefaultConnectionConfig(
                                   ConnectionConfig.custom().setTimeToLive(-1, TimeUnit.MILLISECONDS).build())
                           .setDefaultTlsConfig(
                                   TlsConfig.custom().setVersionPolicy(HttpVersionPolicy.NEGOTIATE).build())
                           .setTlsStrategy(ClientTlsStrategyBuilder.create()
                                   .setSslContext(SSLContexts.createSystemDefault())
                                   .build())
                           .build();
   
           var client = HttpAsyncClientBuilder.create()
                   // Set maxConcurrentStreams to 100 to match the concurrent stream limit of the FCM backend.
                   .setH2Config(H2Config.custom().setMaxConcurrentStreams(100).build())
                   .setHttp1Config(Http1Config.DEFAULT)
                   .setConnectionManager(connectionManager)
                   .setRoutePlanner(new SystemDefaultRoutePlanner(ProxySelector.getDefault()))
                   .disableRedirectHandling()
                   // disable gzip encoding to work around https://github.com/firebase/firebase-admin-java/issues/1173
                   .disableContentCompression()
                   .disableAutomaticRetries();
   
           // configure the firebase client
           FirebaseOptions options = FirebaseOptions.builder()
                   // set the http transport
                   .setHttpTransport(new ApacheHttp2Transport(client.build()))
   
          ...
   

   I am not suggesting this is the best way to fix this, but it at least seems to confirm @papegaaij assumption about the cause. Downgrading to version 9.6.0 also works...
5. jonathanedey commented on Feb 3, 2026

   

   jonathanedey

   on Feb 3, 2026

   Contributor

   More actions

   Hey folks, thanks for flagging this. We are looking into this issue and can confirm the double compression happening here.

   For now developers wanting to use Apache HttpClient 5.6+, similar to what @marksulls said, we recommend applying the disableContentCompression() method to your default or custom clients.

   HttpAsyncClientBuilder builder = ApacheHttp2Transport.defaultHttpAsyncClientBuilder();
   CloseableHttpAsyncClient client = builder.disableContentCompression().build();
   HttpTransport transport = new ApacheHttp2Transport(client);
   FirebaseApp app = FirebaseApp.initializeApp(FirebaseOptions.builder()
       .setHttpTransport(transport)
       .build());

   We'll update here once we have a fix.
6. jonathanedey

   linked a pull request that will close this issuefix: Reimplement HTTP/2 response entity consumption using ApacheHttp2AsyncEntityConsumer and ApacheHttp2Entity #1181on Feb 18, 2026
7. jonathanedey

   closed this as completedin #1181on Feb 18, 2026