Introduction
As part of enabling Google APIs or Firebase services in your Android
application you may have to add the google-services
plugin to your
build.gradle
file:
dependencies {
classpath 'com.google.gms:google-services:4.4.2'
// ...
}
The google-services
plugin has two main functions:
- Process the
google-services.json
file and produce Android resources that can be used in your application's code. See Adding the JSON File more information. Add dependencies for basic libraries required for the services you have enabled. This step requires that you apply the Google Services Gradle plugin in your
app/build.gradle
file, like so:
apply plugin: 'com.google.gms.google-services'
You can see the result of this step by running
./gradlew :app:dependencies
.
Adding the JSON File
The google-services.json
file is generally placed in the
app/
directory (at the root of the Android Studio app module). As
of version 2.2.0
the plugin supports build type and product flavor
specific JSON files. All of the following directory structures are valid:
// dogfood and release are build types. app/ google-services.json src/dogfood/google-services.json src/release/google-services.json ...
Note: Providing a google-services.json file in the release directory allows you to maintain a separate Firebase project for your production APKs.
When product flavors are in use these more complicated directory structures are also valid.
// free and paid are product flavors. app/ google-services.json src/dogfood/paid/google-services.json src/release/free/google-services.json ...
Processing the JSON File
The google-services.json
file has the following basic structure:
{ "project_info": {...}, "client": [...], }
The project_info
object contains general information about your
project, while each member of the client
array contains information
about the clients (Android apps) that you have added to the project.
When processing the JSON file for your Android app, the plugin only uses the
client
object that matches your package name (for the current build
type) based on the following logic:
- For each member of the
client
array:- Check the value of
client_info/android_client_info/package_name
- If the package name matches this value, return the member object.
- Check the value of
- If none of the members of
client
match the package name, an exception is thrown.
For the rest of this document we will use {YOUR_CLIENT}
to refer to
the member of the client
array determined by the procedure above.
The main result of the JSON processing is to produce two XML files which you can reference as Android resources in your Java code. Below is an example of each file:
app/build/generated/res/google-services/{build_type}/values/values.xml
<?xml version="1.0" encoding="utf-8"?> <resources> <! -- Present in all applications --> <string name="google_app_id" translatable="false">1:1035469437089:android:73a4fb8297b2cd4f</string> <! -- Present in applications with the appropriate services configured --> <string name="gcm_defaultSenderId" translatable="false">1035469437089</string> <string name="default_web_client_id" translatable="false">337894902146-e4uksm38sne0bqrj6uvkbo4oiu4hvigl.apps.googleusercontent.com</string> <string name="ga_trackingId" translatable="false">UA-65557217-3</string> <string name="firebase_database_url" translatable="false">https://example-url.firebaseio.com</string> <string name="google_api_key" translatable="false">AIzbSyCILMsOuUKwN3qhtxrPq7FFemDJUAXTyZ8</string> <string name="google_crash_reporting_api_key" translatable="false">AIzbSyCILMsOuUKwN3qhtxrPq7FFemDJUAXTyZ8</string> <string name="project_id" translatable="false">mydemoapp</string> </resources>
app/build/generated/res/google-services/{flavor}/{build_type}/xml/global_tracker.xml
<?xml version="1.0" encoding="utf-8"?> <resources> <string name="ga_trackingId" translatable="false">UA-65557218-3</string> </resources>
Every value in the XML files is present in the google-services.json
file at the locations below. If your Android project has some configuration
that prevents you from using the google-services
plugin, you can
safely recreate the XML files manually using these values:
google_app_id:
{YOUR_CLIENT}/client_info/mobilesdk_app_id
gcm_defaultSenderId:
project_info/project_number
default_web_client_id:
{YOUR_CLIENT}/oauth_client/client_id (client_type == 3)
ga_trackingId:
{YOUR_CLIENT}/services/analytics-service/analytics_property/tracking_id
firebase_database_url:
project_info/firebase_url
google_api_key:
{YOUR_CLIENT}/api_key/current_key
google_crash_reporting_api_key:
{YOUR_CLIENT}/api_key/current_key
project_id:
project_info/project_id
Troubleshooting
Q: When building I get the following error message: "File google-services.json is missing from module root folder. The Google Services Plugin cannot function without it".
A: The Firebase console will help you
download the google-services.json
.
In addition, the Quickstart guides for most APIs have instructions for
generating this file.
Once you have downloaded the google-services.json
file, copy it
into the app/
folder of your Android Studio project, or into the
app/src/{build_type}
folder if you are using multiple build types.
Q: I can't find the symbol "R.string.gcm_defaultSenderId", "R.xml.global_tracker", etc.
A: Make sure the package name in your build.gradle
file matches the
package name you entered when creating the google-services.json
file. If you are not sure, run through the getting started flow again and get
a new json file.