Logout user from Google Auth as well

Author: niftynei

app/src/main/java/com/zulip/android/ZulipApp.java

@@ -36,6 +36,7 @@
 import com.zulip.android.networking.response.UserConfigurationResponse;
 import com.zulip.android.networking.response.events.EventsBranch;
 import com.zulip.android.service.ZulipServices;
+import com.zulip.android.util.GoogleAuthHelper;
 import com.zulip.android.util.ZLog;
 
 import java.io.IOException;
@@ -398,6 +399,8 @@ public void logOut() {
         ed.apply();
         this.api_key = null;
         setEventQueueId(null);
+
+        new GoogleAuthHelper().logOutGoogleAuth();
     }
 
     public String getEmail() {
@@ -527,4 +530,5 @@ public void onFailure(Call<ResponseBody> call, Throwable t) {
             }
         });
     }
+
 }

app/src/main/java/com/zulip/android/activities/LoginActivity.java

@@ -346,6 +346,7 @@ private void setupGoogleSignIn() {
                     .build();
 
             mGoogleApiClient.connect();
+
             allowUserToPickAccount();
         } else {
             allowUserToPickAccount();

app/src/main/java/com/zulip/android/util/GoogleAuthHelper.java

@@ -0,0 +1,44 @@
+package com.zulip.android.util;
+
+import android.os.Bundle;
+import android.support.annotation.Nullable;
+import android.util.Log;
+
+import com.google.android.gms.auth.api.Auth;
+import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
+import com.google.android.gms.common.api.GoogleApiClient;
+import com.zulip.android.BuildConfig;
+import com.zulip.android.ZulipApp;
+
+/**
+ * Class to encapsulate logic for the Google Authentication flows
+ */
+
+public class GoogleAuthHelper implements GoogleApiClient.ConnectionCallbacks {
+
+    private GoogleApiClient mGoogleApiClient;
+
+    public void logOutGoogleAuth() {
+        GoogleSignInOptions googleSignInOptions = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
+                .requestEmail()
+                .requestIdToken(BuildConfig.GOOGLE_CLIENT_ID)
+                .build();
+
+        mGoogleApiClient = new GoogleApiClient.Builder(ZulipApp.get())
+                .addApi(Auth.GOOGLE_SIGN_IN_API, googleSignInOptions)
+                .addConnectionCallbacks(this)
+                .build();
+
+        mGoogleApiClient.connect();
+    }
+
+    @Override
+    public void onConnected(@Nullable Bundle bundle) {
+        Auth.GoogleSignInApi.signOut(mGoogleApiClient);
+    }
+
+    @Override
+    public void onConnectionSuspended(int i) {
+        // do nothing
+    }
+}