java.lang.IllegalStateException: Bu özellik yalnızca arka uç örnekler için kullanılabilir

Question

Benim api kaşifimde, bir veri ucuna bir ekleme gerçekleştirirken, bazı verileri firebase'e ekleyen aşağıdaki hatayı alıyorum.

503 

- Show headers - 

{ 
"error": { 
    "errors": [ 
    { 
    "domain": "global", 
    "reason": "backendError", 
    "message": "java.lang.IllegalStateException: This feature is only available to backend instances." 
    } 
    ], 
    "code": 503, 
    "message": "java.lang.IllegalStateException: This feature is only available to backend instances." 
} 
} 

Ayrıca, aşağıdaki kodyu, firebase'in statik nesne başvurusu olduğu bir uç nokta sınıfı içinde kullanıyorum.

FirebaseOptions options = new FirebaseOptions.Builder() 
     .setServiceAccount(servletContext.getResourceAsStream("/WEB-INF/google-services.json")) 
     .setDatabaseUrl("https://contactifyapp.firebaseio.com/") 
     .build(); 

if (firebaseApp == null) 
    firebaseApp = FirebaseApp.initializeApp(options); 

// As an admin, the app has access to read and write all data, regardless of Security Rules 
DatabaseReference ref = FirebaseDatabase 
     .getInstance() 
     .getReference(); 
String data = runMeNow.getData(); 
JSONObject jsonObject = new JSONObject(data); 
Random rand = new Random(); 
ref.child(Keys.CONTACT_INFO).child("child").child(Keys.USER_INFO).setValue(jsonObject.get(Keys.USER_INFO)); 

günlükleri sunucuda aşağıdaki gibidir:

19:30:43.061 
com.google.api.server.spi.SystemService invokeServiceMethod: exception occurred while calling backend method 
java.lang.IllegalStateException: This feature is only available to backend instances. 
    at com.google.appengine.api.system.SystemServiceImpl.translateException(SystemServiceImpl.java:40) 
    at com.google.appengine.api.system.SystemServiceImpl.startBackgroundRequest(SystemServiceImpl.java:28) 
    at com.google.firebase.database.utilities.DefaultRunLoop$FirebaseThreadFactory.newThread(DefaultRunLoop.java:13) 
    at java.util.concurrent.ThreadPoolExecutor$Worker.<init>(ThreadPoolExecutor.java:600) 
    at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:943) 
    at java.util.concurrent.ThreadPoolExecutor.ensurePrestart(ThreadPoolExecutor.java:1635) 
    at java.util.concurrent.ScheduledThreadPoolExecutor.delayedExecute(ScheduledThreadPoolExecutor.java:307) 
    at java.util.concurrent.ScheduledThreadPoolExecutor.schedule(ScheduledThreadPoolExecutor.java:526) 
    at com.google.firebase.database.connection.PersistentConnectionImpl.doIdleCheck(PersistentConnectionImpl.java:1098) 
    at com.google.firebase.database.connection.PersistentConnectionImpl.<init>(PersistentConnectionImpl.java:266) 
    at com.google.firebase.database.core.GaePlatform.newPersistentConnection(GaePlatform.java:128) 
    at com.google.firebase.database.core.Context.newPersistentConnection(Context.java:195) 
    at com.google.firebase.database.core.Repo.<init>(Repo.java:64) 
    at com.google.firebase.database.core.RepoManager.createLocalRepo(RepoManager.java:87) 
    at com.google.firebase.database.core.RepoManager.createRepo(RepoManager.java:28) 
    at com.google.firebase.database.FirebaseDatabase.ensureRepo(FirebaseDatabase.java:249) 
    at com.google.firebase.database.FirebaseDatabase.getReference(FirebaseDatabase.java:114) 
    at com.safran.contactify.backend.RunMeNowEndpoint.insert(RunMeNowEndpoint.java:105) 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    at java.lang.reflect.Method.invoke(Method.java:44) 
    at com.google.api.server.spi.SystemService.invokeServiceMethod(SystemService.java:363) 
    at com.google.api.server.spi.SystemServiceServlet.execute(SystemServiceServlet.java:113) 
    at com.google.api.server.spi.SystemServiceServlet.doPost(SystemServiceServlet.java:71) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:637) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) 
    at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166) 
    at com.googlecode.objectify.ObjectifyFilter.doFilter(ObjectifyFilter.java:48) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388) 
    at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) 
    at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182) 
    at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765) 
    at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418) 
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) 
    at org.mortbay.jetty.Server.handle(Server.java:326) 
    at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542) 
    at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923) 
    at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404) 
    at com.google.tracing.TraceContext$TraceContextRunnable.runInContext(TraceContext.java:439) 
    at com.google.tracing.TraceContext$TraceContextRunnable$1.run(TraceContext.java:446) 
    at com.google.tracing.CurrentContext.runInContext(CurrentContext.java:256) 
    at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContextNoUnref(TraceContext.java:310) 
    at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContext(TraceContext.java:302) 
    at com.google.tracing.TraceContext$TraceContextRunnable.run(TraceContext.java:443) 
    at java.lang.Thread.run(Thread.java:745) 

Answer 1

App Engine ile Firebase kullanmak için, manuel ölçekleme kullanmalıdır. Bunun nedeni Firebase'in değişiklikleri dinlemek için arka plan iş parçacıklarını kullanması ve App Engine'in yalnızca elle ölçeklenen arka uç örneklerinde uzun ömürlü arka plan iş parçacıklarına izin vermesidir. Bu bakılmaksızın taleplerin miktarının hizmet sadece bir örneğini orada olacağı anlamına gelir Docs göre senin appengine-web.xml

<manual-scaling> 
    <instances>1</instances> 
</manual-scaling>