Android Purchases Code

Please be mindful. This page is almost identical to the previous with exceptions in the function name and code.

These codes will allow you to acknowledge and verify purchases or subscriptions. There is 1 call for each type of transaction.

1. To get started, go to console.google.cloud.com/functions

2. Click Create Function

3. Give your new function a meaningful name

androidPurchaseHandler should be the name you use here

4. Save the trigger type

5. Copy the code below and click the blue "next" button

Copy Me

androidPurchaseHandler.

///purchase handler
const functions = require("firebase-functions");
const admin = require("firebase-admin");
const googleServiceAccountKey = require("./serviceAccount.json");
admin.initializeApp({
  credential: admin.credential.cert(googleServiceAccountKey),
});
const {google} = require("googleapis");
const axios = require("axios");

exports.androidPurchaseHandler = functions.https.onRequest((request, response) => {
 
  const {purchaseObject, type} = request.body;
  // get the token and product id from the request
  const purchaseToken = purchaseObject.purchaseToken;
  const productId = purchaseObject.productId;
  functions.logger.info(`trying to handle ${type} for the follow ${JSON.stringify(purchaseObject)}`);
  // set your package id
  const packageID = "edu.fit.my.jgibb2018.pob";

  const returnTheResponse = (data) => {
    response.status(200).send(data);
  };

  const acknowledgePurchase = (err, tokens) => {
    functions.logger.info("acknowledging purchase");
    const config = {
      method: "post",
      url: `https://androidpublisher.googleapis.com/androidpublisher/v3/applications/${packageID}/purchases/products/${productId}/tokens/${purchaseToken}:acknowledge`,
      headers: {
        "Authorization": `Bearer ${tokens.access_token}`,
      },
    };

    axios(config)
        .then(function(r) {
          functions.logger.info("acknowledge success. returning ", JSON.stringify(r.data));

          returnTheResponse(r.data);
        })
        .catch(function(e) {
          returnTheResponse(JSON.stringify({error: e.data, status: e.status, message: e.message}));
        });
  };

  const verifyPurchase = (err, tokens) => {
    functions.logger.info("verifying purchase");
    const config = {
      method: "get",
      url: `https://androidpublisher.googleapis.com/androidpublisher/v3/applications/${packageID}/purchases/products/${productId}/tokens/${purchaseToken}`,
      headers: {
        "Authorization": `Bearer ${tokens.access_token}`,
      },
    };

    axios(config)
        .then(function(r) {
          functions.logger.info("verify success. returning ", JSON.stringify(r.data));
          returnTheResponse(r.data);
        })
        .catch(function(e) {
          returnTheResponse(JSON.stringify({error: e.data, status: e.status, message: e.message}));
        });
  };

  const getAccessToken = () => {
    const jwtClient = new google.auth.JWT(
        googleServiceAccountKey.client_email,
        null,
        googleServiceAccountKey.private_key,
        ["https://www.googleapis.com/auth/androidpublisher"],
        null,
    );
    try {
      functions.logger.info("type is ", type);
      if (type == "purchaseAcknowledge") {
        jwtClient.authorize(acknowledgePurchase);
      } else {
        jwtClient.authorize(verifyPurchase);
      }
    } catch (error) {
      functions.logger.log(error);
      response.status(500).send("getting auth", error);
    }
  };

  getAccessToken();
});

6. Clear the default and paste the copied code into the code

7. Update the package.json file

copy and paste this over the default code

{
  "name": "sample-http",
  "version": "0.0.1",
  "dependencies": {
     "axios": "^0.26.0",
     "googleapis": "^97.0.0",
     "firebase-functions": "^3.18.0",
     "firebase-admin": "^10.0.2"
   }
}

8. Set the name of the functions entry point

the name used here should match the name used in Step 3 above

9. Click the plus icon to create a new file and name it "serviceAccount.json"

10. Copy and paste the content of this projects service account file from your computer into this newly created file.

11. Deploy the function

12. Set function invocation privacy permissions

This allows any device with your endpoint URL the ability to verify purchases made via your app

1. Go to https://console.cloud.google.com/functions/list

2. Select the function you want to make public. (the function you just created)

3. Click the Permissions tab.

4. Click Add Principle

5. In the Add members field, type allUsers

6. Select the Cloud Function Invoker role from the Select a role drop-down menu.

7. Click Add.