Authenticating to HashiCorp Vault using Google Cloud IAM

Wednesday, August 16, 2017

Applications often require access to small pieces of sensitive data at build or run time, referred to as secrets. Secrets are generally more sensitive than other environment variables or parts of your repository as they may grant access to additional data, such as user data.

HashiCorp Vault is a popular open source tool for secret management, which allows a developer to store, manage and control access to tokens, passwords, certificates, API keys and other secrets. Vault has many options for authentication, called authentication backends. These allow developers to use many kinds of identities to access Vault, including tokens, or usernames and passwords. As the number of developers on a team grows, these kinds of authentication options become impractical; and in enterprise scenarios, managing and auditing these identities becomes burdensome.

Today, we are pleased to announce a Google Cloud Platform IAM authentication backend for Vault. This allows a developer to use an existing IAM identity to authenticate to Vault. Using a service account, you can sign a JWT to show it came from a particular account, and use that to authenticate to Vault. Learn more in the documentation.

The following example in Go shows how a user can authenticate with Vault using this backend. This example assumes the Vault server has already been mounted at auth/gcp and configured.
package main

import (
 vaultapi ""

func main() {
 // Start [PARAMS]
 project := "project-123456"
 serviceAccount := ""
 credsPath := "path/to/creds.json"

 os.Setenv("VAULT_ADDR", "")
 defer os.Setenv("VAULT_ADDR", "")
 // End [PARAMS]

 // Start [GCP IAM Setup]
 jsonBytes, err := ioutil.ReadFile(credsPath)
 if err != nil {
 config, err := google.JWTConfigFromJSON(jsonBytes, iam.CloudPlatformScope)
 if err != nil {

 httpClient := config.Client(oauth2.NoContext)
 iamClient, err := iam.New(httpClient)
 if err != nil {
 // End [GCP IAM Setup]
 // 1. Generate signed JWT using IAM.
 resourceName := fmt.Sprintf("projects/%s/serviceAccounts/%s", project, serviceAccount)
 jwtPayload := map[string]interface{}{
  "aud": "auth/gcp/login",
  "sub": serviceAccount,
  "exp": time.Now().Add(time.Minute * 10).Unix(),

 payloadBytes, err := json.Marshal(jwtPayload)
 if err != nil {
 signJwtReq := &iam.SignJwtRequest{
  Payload: string(payloadBytes),

 resp, err := iamClient.Projects.ServiceAccounts.SignJwt(
resourceName, signJwtReq).Do()
 if err != nil {

 // 2. Send signed JWT in login request to Vault.
 vaultClient, err := vaultapi.NewClient(vaultapi.DefaultConfig())
 if err != nil {

 vaultResp, err := vaultClient.Logical().Write(
   "role": "test",
   "jwt":  resp.SignedJwt,

 if err != nil {

 // 3. Use auth token from response.
 log.Println("Access token %s", vaultResp.Auth.ClientToken)
 // ...

Vault is just one way of managing secrets in development. For further reading on choosing a solution that’s right for you, see Google Cloud Platform’s documentation on Secret Management.

By Emily Ye, Software Engineer

Making Great Mobile Games with Firebase

Tuesday, August 15, 2017

So much goes into building and maintaining a mobile game. Let’s say you want to ship it with a level builder for sharing content with other players and, looking forward, you want to roll out new content and unlockables linked with player behavior. Of course, you also need players to be able to easily sign into your soon-to-be hit game.

With a DIY approach, you’d be faced with having to build user management, data storage, server side logic, and more. This will take a lot of your time, and importantly, it would take critical resources away from what you really want to do: build that amazing new mobile game!

Our Firebase SDKs for Unity and C++ provide you with the tools you need to add these features and more to your game with ease. Plus, to help you better understand how Firebase can help you build your next chart-topper, we’ve built a sample game in Unity and open sourced it: MechaHamster. Check it out on Google Play or download the project from GitHub to see how easy it is to integrate Firebase into your game.
Before you dive into the code for Mecha Hamster, here’s a rundown of the Firebase products that can help your game be successful.


One of the best tools you have to maintain a high-performing game is your analytics. With Google Analytics for Firebase, you can see where your players might be struggling and make adjustments as needed. Analytics also integrates with Adwords and other major ad networks to maximize your campaign performance. If you monetize your game using AdMob, you can link your two accounts and see the lifetime value (LTV) of your players, from in-game purchases and AdMob, right from your Analytics console. And with Streamview, you can see how players are interacting with your game in realtime.

Test Lab for Android - Game Loop Test

Before releasing updates to your game, you’ll want to make sure it works correctly. However, manual testing can be time consuming when faced with a large variety of target devices. To help solve this, we recently launched Firebase Test Lab for Android Game Loop Test at Google I/O. If you add a demo mode to your game, Test Lab will automatically verify your game is working on a wide range of devices. You can read more in our deep dive blog post here.


Another thing you’ll want to be sure to take care of before launch is easy sign-in, so your users can start playing as quickly as possible. Firebase Authentication can help by handling all sign-in and authentication, from simple email + password logins to support for common identity providers like Google, Facebook, Twitter, and Github. Just announced recently at I/O, Firebase also now supports phone number authentication. And Firebase Authentication shares state cross-device, so your users can pick up where they left off, no matter what platforms they’re using.

Remote Config

As more players start using your game, you realize that there are few spots that are frustrating for your audience. You may even see churn rates start to rise, so you decide that you need to push some adjustments. With Firebase Remote Config, you can change values in the console and push them out to players. Some players having trouble navigating levels? You can adjust the difficulty and update remotely. Remote Config can even benefit your development cycle; team members can tweak and test parameters without having to make new builds.

Realtime Database

Now that you have a robust player community, you’re probably starting to see a bunch of great player-built levels. With Firebase Realtime Database, you can store player data and sync it in real-time, meaning that the level builder you’ve built can store and share data easily with other players. You don't need your own server and it’s optimized for offline use. Plus, Realtime Database integrates with Firebase Auth for secure access to user specific data.

Cloud Messaging & Dynamic Links

A few months go by and your game is thriving, with high engagement and an active community. You’re ready to release your next wave of new content, but how can you efficiently get the word out to your users? Firebase Cloud Messaging lets you target messages to player segments, without any coding required. And Firebase Dynamic Links allow your users to share this new content — or an invitation to your game — with other players. Dynamic Links survive the app install process, so a new player can install your app and then dive right into the piece of content that was shared with him or her.

At Firebase, our mission is to help mobile developers build better apps and grow successful businesses. When it comes to games, that means taking care of the boring stuff, so you can focus on what matters — making a great game. Our mobile SDKs for C++ and Unity are available now at

By Darin Hilton, Art Director

Professors from Around the World Get Their Students into HFOSS

Friday, July 21, 2017

Over the last four years instructors from around the world have gathered for the Professors’ Open Source Software Experience (POSSE) workshop to integrate open source concepts into their curriculum. At each event, professors make more progress toward providing students with hands on experience via contributions to humanitarian free and open source software (HFOSS).

This year Google was proud to not only host a workshop at our San Francisco office in April, but also to collaborate with the organizers to bring a POSSE workshop to Europe for the first time.
POSSE workshop leaders, from left to right: Clif Kussmaul (Muhlenburg College), Lori Postner (Nassau Community College), Stoney Jackson (Western New England University),  Heidi Ellis (Western New England University), Greg Hislop (Drexel University), and Darci Burdge (Nassau Community College).
The workshop in Italy was led by Dr. Gregory Hislop from Drexel University, and Drs. Heidi Ellis and Stoney Jackson from Western New England University, and brought together 20 instructors from Germany, Hungary, India, Italy, Macedonia, Qatar, Spain, Swaziland, the United Kingdom, and the United States. This was the most geographically diverse workshop to date!
Group photos in San Francisco, USA on April 22, 2017 (left) and Bologna, Italy on July 1, 2017 (right).
What’s next for POSSE? University instructors from institutions in the US can apply now to participate in the next workshop, November 16-18 in Raleigh, NC and join their peers in the community of instructors weaving HFOSS into their curriculum.

By Helen Hu, Google Open Source