Exception at AppSyncSigV4SignerInterceptor

[yong0726]

In our production app, the below crash has been detected many times via Firebase Crashlytics. please help me.

Fatal Exception: com.amazonaws.AmazonClientException
Unable to execute HTTP request: Unable to resolve host "cognito-identity.us-east-1.amazonaws.com": No address associated with hostname
com.amazonaws.http.AmazonHttpClient.executeHelper (AmazonHttpClient.java:441)
com.amazonaws.http.AmazonHttpClient.execute (AmazonHttpClient.java:212)
com.amazonaws.services.cognitoidentity.AmazonCognitoIdentityClient.invoke (AmazonCognitoIdentityClient.java:559)
com.amazonaws.services.cognitoidentity.AmazonCognitoIdentityClient.getCredentialsForIdentity (AmazonCognitoIdentityClient.java:389)
com.amazonaws.auth.CognitoCredentialsProvider.populateCredentialsWithCognito (CognitoCredentialsProvider.java:748)
com.amazonaws.auth.CognitoCredentialsProvider.startSession (CognitoCredentialsProvider.java:674)
com.amazonaws.auth.CognitoCredentialsProvider.getCredentials (CognitoCredentialsProvider.java:445)
com.amazonaws.auth.CognitoCachingCredentialsProvider.getCredentials (CognitoCachingCredentialsProvider.java:485)
com.amazonaws.auth.CognitoCachingCredentialsProvider.getCredentials (CognitoCachingCredentialsProvider.java:77)
com.amazonaws.mobileconnectors.appsync.sigv4.AppSyncSigV4SignerInterceptor.intercept (AppSyncSigV4SignerInterceptor.java:123)
okhttp3.internal.http.RealInterceptorChain.proceed (RealInterceptorChain.java:92)
okhttp3.internal.http.RealInterceptorChain.proceed (RealInterceptorChain.java:67)
okhttp3.RealCall.getResponseWithInterceptorChain (RealCall.java:185)
okhttp3.RealCall$AsyncCall.execute (RealCall.java:135)
okhttp3.internal.NamedRunnable.run (NamedRunnable.java:32)
java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1133)
java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:607)
java.lang.Thread.run (Thread.java:761)

The below is our initialized code.

private AppSyncClient(Context context) {
        mContext = context.getApplicationContext();

        mCredentialsProvider = new CognitoCachingCredentialsProvider(
            context,
            Constants.COGNITO_IDENTITY,
            Constants.COGNITO_REGION
        );

        mAppSyncClient = AWSAppSyncClient.builder()
            .context(context)
            .credentialsProvider(mCredentialsProvider)
            .region(Constants.APPSYNC_REGION)
            .serverUrl(Constants.getAppSyncUrl())
            .build();

        mS3 = new AmazonS3Client(mCredentialsProvider);
        mS3.setRegion(Region.getRegion(Constants.S3_REGION));
    }

the SDK version is 2.6.17

[rohandubal]

Hi, This might be a transient error due to network not being available. One improvement which we can do on this is to catch the error in the SDK and surface it in onError callback, so that the request can be retried if desired and also not cause a crash. Would this work for you @yong0726 ?

Thanks,
Rohan

[yong0726]

@rohandubal I think it would be better if the SDK can retry automatically by itself when the network comes back to normal. because automatic management of network connection is one of the main feature of AppSync.

Regards,
Yongjae

[minbi]

Hi @yong0726 ,

In our experience, this error does not resolve until the app is restarted or in some cases re-installed. Retrying the request would not help.

We will investigate the issue and reply here when we have more information.

[minbi]

We have a fix that will prevent crashing, but the error will be surfaced in the onError callback.

[minbi]

This issue should be resolve with release 2.6.20. Re-open if necessary