[Firebase Admin SDK] Troubles while using Firebase Admin SDK to modify data in Firestore

[KevinKons]

I'm using Windows 10 with Java 8 and firebase admin version 6.12.0

I am trying to use the Firebase Admin SDK to add data to Firestore. I am following these documentations: https://firebase.google.com/docs/admin/setup#add_the_sdk and
https://firebase.google.com/docs/database/admin/save-data

The Service account key that I generated was saved as Json file in the root of the project.

This is how my build.gradle dependencies looks like:

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'
    compile group: 'com.google.firebase', name: 'firebase-admin', version: '6.12.0'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
}

This is how my Main Java class looks like:

public class Main {

    public static void main(String[] args) throws IOException, ExecutionException, InterruptedException {
        FirebaseService firebaseService = new FirebaseService();
        firebaseService.initializeFirebaseApp();

        HashMap<String, Object> pharmacies = new HashMap<>();
        pharmacies.put("address", "Rua emídio goulart, 300");

        firebaseService.writeToDb(pharmacies);
    }
}

This is how the class FirebaseService looks like:

import com.google.api.core.ApiFuture;
import com.google.auth.oauth2.GoogleCredentials;
import com.google.cloud.firestore.Firestore;
import com.google.cloud.firestore.WriteResult;
import com.google.firebase.FirebaseApp;
import com.google.firebase.FirebaseOptions;
import com.google.firebase.cloud.FirestoreClient;

import java.io.FileInputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.concurrent.ExecutionException;

public class FirebaseService {

    private Firestore db;

    public void initializeFirebaseApp() throws IOException {
        FileInputStream serviceAccount = new FileInputStream("./ServiceAccountKey.json");

        FirebaseOptions options = new FirebaseOptions.Builder()
                .setCredentials(GoogleCredentials.fromStream(serviceAccount))
                .setDatabaseUrl("https://tests-212aa.firebaseio.com")
                .build();

        FirebaseApp.initializeApp(options);

        db = FirestoreClient.getFirestore();

    }

    public void writeToDb(HashMap data) throws ExecutionException, InterruptedException {
        ApiFuture<WriteResult> future = db.collection("pharmacies").document("farma").set(data);
        System.out.println(future.get().getUpdateTime());
    }
}

This is the stack trace:

Exception in thread "main" java.util.concurrent.ExecutionException: com.google.api.gax.rpc.UnavailableException: io.grpc.StatusRuntimeException: UNAVAILABLE: Credentials failed to obtain metadata
	at com.google.common.util.concurrent.AbstractFuture.getDoneValue(AbstractFuture.java:552)
	at com.google.common.util.concurrent.AbstractFuture.get(AbstractFuture.java:533)
	at com.google.common.util.concurrent.FluentFuture$TrustedFuture.get(FluentFuture.java:84)
	at com.google.common.util.concurrent.ForwardingFuture.get(ForwardingFuture.java:62)
	at com.pharmapp.productregistration.FirebaseService.writeToDb(FirebaseService.java:40)
	at com.pharmapp.productregistration.Main.main(Main.java:17)
Caused by: com.google.api.gax.rpc.UnavailableException: io.grpc.StatusRuntimeException: UNAVAILABLE: Credentials failed to obtain metadata
	at com.google.api.gax.rpc.ApiExceptionFactory.createException(ApiExceptionFactory.java:69)
	at com.google.api.gax.grpc.GrpcApiExceptionFactory.create(GrpcApiExceptionFactory.java:72)
	at com.google.api.gax.grpc.GrpcApiExceptionFactory.create(GrpcApiExceptionFactory.java:60)
	at com.google.api.gax.grpc.GrpcExceptionCallable$ExceptionTransformingFuture.onFailure(GrpcExceptionCallable.java:97)
	at com.google.api.core.ApiFutures$1.onFailure(ApiFutures.java:68)
	at com.google.common.util.concurrent.Futures$CallbackListener.run(Futures.java:982)
	at com.google.common.util.concurrent.DirectExecutor.execute(DirectExecutor.java:30)
	at com.google.common.util.concurrent.AbstractFuture.executeListener(AbstractFuture.java:1138)
	at com.google.common.util.concurrent.AbstractFuture.complete(AbstractFuture.java:957)
	at com.google.common.util.concurrent.AbstractFuture.setException(AbstractFuture.java:748)
	at io.grpc.stub.ClientCalls$GrpcFuture.setException(ClientCalls.java:515)
	at io.grpc.stub.ClientCalls$UnaryStreamToFuture.onClose(ClientCalls.java:490)
	at io.grpc.PartialForwardingClientCallListener.onClose(PartialForwardingClientCallListener.java:39)
	at io.grpc.ForwardingClientCallListener.onClose(ForwardingClientCallListener.java:23)
	at io.grpc.ForwardingClientCallListener$SimpleForwardingClientCallListener.onClose(ForwardingClientCallListener.java:40)
	at io.grpc.internal.CensusStatsModule$StatsClientInterceptor$1$1.onClose(CensusStatsModule.java:700)
	at io.grpc.PartialForwardingClientCallListener.onClose(PartialForwardingClientCallListener.java:39)
	at io.grpc.ForwardingClientCallListener.onClose(ForwardingClientCallListener.java:23)
	at io.grpc.ForwardingClientCallListener$SimpleForwardingClientCallListener.onClose(ForwardingClientCallListener.java:40)
	at io.grpc.internal.CensusTracingModule$TracingClientInterceptor$1$1.onClose(CensusTracingModule.java:399)
	at io.grpc.internal.ClientCallImpl.closeObserver(ClientCallImpl.java:510)
	at io.grpc.internal.ClientCallImpl.access$300(ClientCallImpl.java:66)
	at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl.close(ClientCallImpl.java:630)
	at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl.access$700(ClientCallImpl.java:518)
	at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl$1StreamClosed.runInternal(ClientCallImpl.java:692)
	at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl$1StreamClosed.runInContext(ClientCallImpl.java:681)
	at io.grpc.internal.ContextRunnable.run(ContextRunnable.java:37)
	at io.grpc.internal.SerializingExecutor.run(SerializingExecutor.java:123)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
Caused by: io.grpc.StatusRuntimeException: UNAVAILABLE: Credentials failed to obtain metadata
	at io.grpc.Status.asRuntimeException(Status.java:533)
	... 24 more
Caused by: java.io.IOException: Error getting access token for service account: 400 Bad Request
{
  "error": "invalid_grant",
  "error_description": "Invalid JWT: Token must be a short-lived token (60 minutes) and in a reasonable timeframe. Check your iat and exp values and use a clock with skew to account for clock differences between systems."
}
	at com.google.auth.oauth2.ServiceAccountCredentials.refreshAccessToken(ServiceAccountCredentials.java:432)
	at com.google.auth.oauth2.OAuth2Credentials.refresh(OAuth2Credentials.java:157)
	at com.google.auth.oauth2.OAuth2Credentials.getRequestMetadata(OAuth2Credentials.java:145)
	at com.google.auth.Credentials.blockingGetToCallback(Credentials.java:112)
	at com.google.auth.Credentials$1.run(Credentials.java:98)
	... 7 more
Caused by: com.google.api.client.http.HttpResponseException: 400 Bad Request
{
  "error": "invalid_grant",
  "error_description": "Invalid JWT: Token must be a short-lived token (60 minutes) and in a reasonable timeframe. Check your iat and exp values and use a clock with skew to account for clock differences between systems."
}
	at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:1097)
	at com.google.auth.oauth2.ServiceAccountCredentials.refreshAccessToken(ServiceAccountCredentials.java:429)
	... 11 more

The line referenced in the stacktrace as at com.pharmapp.productregistration.FirebaseService.writeToDb(FirebaseService.java:40) is this one System.out.println(future.get().getUpdateTime());

I don't know what is going wrong I am doing everything as the documentation says.

[dmitry-fa]

The very similar issue: googleapis/google-cloud-python#3100

The root cause: the clock on the local machine is out of sync with the real world.
I managed to reproduce the issue on my local environment. To do that I turned the 'Set time automatically' option off and moved the clock one hour ahead. Then I ran your example and got exactly the same exception.
Moving the clock one hour back made the exception disappear.

[KevinKons]

Thanks, that solved my problem!