I have not much knowledge with JavaScript, I got to this function partly guessing from all that I have read, I will appreciate corrections, I know there is room for improvement but it does the validation.
This is the function I'm using to validate my purchases:
const functions = require('firebase-functions');
const admin = require('firebase-admin');
const {google} = require("googleapis");
const publisher = google.androidpublisher('v2');
const authClient = new google.auth.JWT({
email: 'Service Account Email',
key: '-----BEGIN PRIVATE KEY-----\n**********************************************************************************==\n-----END PRIVATE KEY-----\n',
scopes: ['https://www.googleapis.com/auth/androidpublisher']
});
admin.initializeApp();
exports.validatePurchases = functions.database
.ref('/purchases/{uId}/{orderId}')
.onCreate((event, context) => {
const purchase = event.val();
if (purchase.is_processed === true) {
console.log('Purchase already processed!, exiting');
return null;
}
const orderId = context.params.orderId;
const dbRoot = event.ref.root;
const package_name = purchase.package_name;
const sku = purchase.sku;
const my_token = purchase.token;
authClient.authorize((err, result) => {
if (err) {
console.log(err);
}
publisher.purchases.products.get({
auth: authClient,
packageName: package_name,
productId: sku,
token: my_token
}, (err, response) => {
if (err) {
console.log(err);
}
// Result Status must be equals to 200 so that the purchase is valid
if (response.status === 200) {
return event.ref.child('is_validated').set(true);
} else {
return event.ref.child('is_validated').set(false);
}
});
});
return null;
});
UPDATE:
I just found out that when using Promo Codes this will fail as orderId is empty for Promo Codes.
Using Promises
return authClient.authorize()
// authClient.authorize() returns a credentials Object
.then(credentials => {
return publisher.purchases.products.get({
auth: authClient,
packageName: packageName,
productId: sku,
token: token
});
})
// publisher.purchases.products.get() Returns a axiosResponse object with Purchase data within and the status that should be enough for the validation
.then(axiosResponse => {
if (axiosResponse.status === 200 && axiosResponse.data.purchaseState === 0) {
// Your purchase is valid, do your thing
} else {
return event.ref.set(null);
}
})
.catch(reason => {
console.log(`Rejection Code: ${reason.code}`);
console.log(`Rejection Message: ${reason.message}`);
return event.ref.set(null);
});
It is my understanding that axiosResponse.status === 200 should be enough for verifying a purchase, note however that axiosResponse.data holds the data from the purchase Schema$ProductPurchase where you can check other values from the Purchase. Which I find interesting if you are using "Licensing Testing" or "Promo Codes". In this sample I'm using axiosResponse.data.purchaseState to check that the purchase is still valid(maybe unnecesary...)
