How to integrate Zendesk Mobile SDK with Firebase using AWS Lambda or Google Cloud Functions

deploy.sh

#!/usr/bin/env bash

firebase deploy --only functions

index.js

'use strict';

const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
var jwt = require('jwt-simple');
var uuid = require('uuid');
var url = require('url');

var subdomain = 'dev-ops-notes'; // You Zendesk sub-domain 
var shared_key = '.....'; // Zendesk provided shared key

exports.jwt_auth = functions.https.onRequest((req, res) => {
    // Uncomment the following code if you want to 
    //console.log('Request method', req.method);
    //console.log('Request: ', req);
    //console.log('Body: ', req.body);
    //console.log('Query: ', req.query);

    if (!req.body.user_token) {
        console.error('No jwt token provided in URL');
        res.status(401).send('Unauthorized');
        return;
    }

    const jwt_token = req.body.user_token;

    console.log("Verifying token...");
    admin.auth().verifyIdToken(jwt_token).then(decodedIdToken => {
        console.log('ID Token correctly decoded', decodedIdToken);
        let user = decodedIdToken;

        var displayName = user.email;
        if (user.displayName != null) { 
            displayName = user.displayName;
        }

        var payload = {
            iat: (new Date().getTime() / 1000),
            jti: uuid.v4(),
            name: displayName,
            email: user.email
        };

        // encode
        var token = jwt.encode(payload, shared_key);
        console.log('Token', token)
        var redirect = 'https://' + subdomain + '.zendesk.com/access/jwt?jwt=' + token;

        var query = url.parse(req.url, true).query;

        if(query['return_to']) {
            redirect += '&return_to=' + encodeURIComponent(query['return_to']);
        }
        console.log('Redirect response', redirect)
        let response = {
            "jwt": token
        }

        res.status(200).send(response)
        return;
    }).catch(error => {
        console.error('Error while verifying Firebase ID token:', error);
        res.status(401).send('Unauthorized');
        return;
    });

});

MyViewController.swift

//Launch MyViewController options
URLProtocol.registerClass(ZDKAuthenticationURLProtocol.self)
let jwtUserIdentity = ZDKJwtIdentity(jwtUserIdentifier:idToken)
ZDKConfig.instance().userIdentity = jwtUserIdentity
let helpCenterContentModel = ZDKHelpCenterOverviewContentModel.defaultContent()
ZDKHelpCenter.presentOverview(self, with: helpCenterContentModel)

MyViewController1.swift

//Support button pressed method content
if let currentUser = Auth.auth().currentUser {
    currentUser.getTokenForcingRefresh(true, completion: { (idToken, error) in
        if let error = error {
            debugPrint("Error obtaining user token: %@", error)
        } else {
            URLProtocol.registerClass(ZDKAuthenticationURLProtocol.self)
            let jwtUserIdentity = ZDKJwtIdentity(jwtUserIdentifier:idToken)
            ZDKConfig.instance().userIdentity = jwtUserIdentity
            // Create a Content Model to pass in
            let helpCenterContentModel = ZDKHelpCenterOverviewContentModel.defaultContent()
            ZDKHelpCenter.presentOverview(self, with: helpCenterContentModel)
        }
    })
}

setup_requirements.sh

#!/usr/bin/env bash

npm install firebase-functions
npm install firebase-admin
npm install jwt-simple
npm install uuid
npm install url