Google androidpublish api access_token

Question

I am working on an Android application with Google Play in-app purchases. I also have a server application(JAVA) working in the background. Whenever the user successfully makes a purchase in the app(purchasing is working), the server application should send a request to Google play to verify the purchase.

Google Play is offering the androidpublisher api for that: developers.google.com/android-publisher/getting_started

The problem is the access_token. Whenever I obtain a new access_token(either with the refresh or new token requesting method), it doesn't work, if I try to use the GET method to ask the information from a purchase inapp item from Google play store(https://developers.google.com/android-publisher/v1/purchases/get) -> it always results in error 401(invalid credential) or 403(access not configured).

after endless trying I find out that I only can get the method working with that link: https://developers.google.com/apis-explorer/#p/androidpublisher/v1.1/androidpublisher.inapppurchases.get, and I can only read the valid access_token from there, and only with that token I can get my server application working but only for one hour, after 1 hour I have to do the same step again...

now I really need a proper way to get a valid access_token with my application

I have researched a lot on internet but I couldn't find something useful. I know that I am not the only one with that problem, maybe someone of you guys know what to do or has already experience with that

Miha Hribar Miha Hribar · Accepted Answer · 2014-06-17T13:07:23

You can use com.google.api-client and google-api-services-androidpublisher libraries.

First go to the project on google developer console (https://console.developers.google.com)

APIs & Auth -> APIs
Enable "Google Play Android Developer API"
Go to Credentials -> Create new Client ID
Select service account
Create client ID
Save the p12 file somewhere safe

Then add the just generated email address for the service account to your google play developer console (https://play.google.com/apps/publish/)

Settings -> User accounts & rights -> Invite new user
Paste the @developer.gserviceaccount.com email account
Select "View financial reports"
Send invitation

Now to the code. Add the following dependencies to your pom.xml file:

<dependency>
    <groupId>com.google.api-client</groupId>
    <artifactId>google-api-client</artifactId>
    <version>1.18.0-rc</version>
</dependency>
<dependency>
    <groupId>com.google.http-client</groupId>
    <artifactId>google-http-client-jackson2</artifactId>
    <version>1.18.0-rc</version>
</dependency>
<dependency>
    <groupId>com.google.apis</groupId>
    <artifactId>google-api-services-androidpublisher</artifactId>
    <version>v1.1-rev25-1.18.0-rc</version>
</dependency>

Then first validate the signature:

byte[] decoded = BASE64DecoderStream.decode(KEY.getBytes());
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PublicKey publicKey = keyFactory.generatePublic(new X509EncodedKeySpec(decoded));
Signature sig = Signature.getInstance("SHA1withRSA");
sig.initVerify(publicKey);
sig.update(signedData.getBytes());
if (sig.verify(BASE64DecoderStream.decode(signature.getBytes())))
{
    // Valid
}

If the signature verifies fetch subscription details:

// fetch signature details from google
HttpTransport httpTransport = GoogleNetHttpTransport.newTrustedTransport();
JsonFactory jsonFactory = JacksonFactory.getDefaultInstance();
GoogleCredential credential = new GoogleCredential.Builder()
    .setTransport(httpTransport)
    .setJsonFactory(jsonFactory)
    .setServiceAccountId(ACCOUNT_ID)
    .setServiceAccountScopes(Collections.singleton("https://www.googleapis.com/auth/androidpublisher"))
    .setServiceAccountPrivateKeyFromP12File(new File("key.p12"))
    .build();

AndroidPublisher pub = new AndroidPublisher.Builder(httpTransport, jsonFactory, credential)
    .setApplicationName(APPLICATION_NAME)
    .build();
AndroidPublisher.Purchases.Get get = pub.purchases().get(
    APPLICATION_NAME,
    PRODUCT_ID,
    token);
SubscriptionPurchase subscription = get.execute();
System.out.println(subscription.toPrettyString());

This will take care of all the token issues by generating a JWT token so you don't have to handle it yourself.

Google androidpublish api access_token

1 Answers