refactor: Improvement/bump gms google auth version (#382)

* allow supplying play services auth version & set default to 21.2.0

* update package.lock json to match current version

* check for nullclients on sign-in & sign-out

* correctly return void after nullClient errors

Author: selcuk-sahin

README.md

@@ -170,6 +170,10 @@ plugin first use `androidClientId` if not found use `clientId` if not found use
 </resources>
 ```
 
+Changing Play Services Auth version (Optional) :
+
+This plugin uses `com.google.android.gms:play-services-auth:21.2.0` by default, you can override it providing `gmsPlayServicesAuthVersion` at `variables.gradle`
+
 **Refresh method**
 
 This method should be called when the app is initialized to establish if the user is currently logged in. If true, the method will return an accessToken, idToken and an empty refreshToken.

android/build.gradle

@@ -3,6 +3,7 @@ ext {
     androidxAppCompatVersion = project.hasProperty('androidxAppCompatVersion') ? rootProject.ext.androidxAppCompatVersion : '1.6.1'
     androidxJunitVersion = project.hasProperty('androidxJunitVersion') ? rootProject.ext.androidxJunitVersion : '1.1.5'
     androidxEspressoCoreVersion = project.hasProperty('androidxEspressoCoreVersion') ? rootProject.ext.androidxEspressoCoreVersion : '3.5.1'
+    gmsPlayServicesAuthVersion = project.hasProperty('gmsPlayServicesAuthVersion') ? rootProject.ext.gmsPlayServicesAuthVersion : '21.2.0'
 }
 
 buildscript {
@@ -57,5 +58,5 @@ dependencies {
     testImplementation "junit:junit:$junitVersion"
     androidTestImplementation "androidx.test.ext:junit:$androidxJunitVersion"
     androidTestImplementation "androidx.test.espresso:espresso-core:$androidxEspressoCoreVersion"
-    implementation 'com.google.android.gms:play-services-auth:18.+'
+    implementation "com.google.android.gms:play-services-auth:$gmsPlayServicesAuthVersion"
 }

android/src/main/java/com/codetrixstudio/capacitor/GoogleAuth/GoogleAuth.java

@@ -78,6 +78,10 @@ public void load() {}
 
   @PluginMethod()
   public void signIn(PluginCall call) {
+    if(googleSignInClient == null){
+      rejectWithNullClientError(call);
+      return;
+    }
     Intent signInIntent = googleSignInClient.getSignInIntent();
     startActivityForResult(call, signInIntent, "signInResult");
   }
@@ -155,6 +159,10 @@ public void refresh(final PluginCall call) {
 
   @PluginMethod()
   public void signOut(final PluginCall call) {
+    if(googleSignInClient == null){
+      rejectWithNullClientError(call);
+      return;
+    }
     googleSignInClient.signOut()
       .addOnSuccessListener(getActivity(), new OnSuccessListener<Void>() {
         @Override
@@ -257,4 +265,8 @@ private static String fromStream(InputStream is) throws IOException {
     reader.close();
     return sb.toString();
   }
+
+  private void rejectWithNullClientError(final PluginCall call) {
+    call.reject("Google services are not ready. Please call initialize() first");
+  }
 }