8486. Continuously Deploy Full Stack React App to Heroku with Travis-CI
Heroku and Travis CI

Introduce how to deploy Code Editor app to Heroku with Travis-CI.

1. CI to Heroku

In the posting Continuously Deploy Full Stack React App to Heroku and Netlify with Travis-CI, I introduced how to deploy the full stack app(server + client) to Heroku and Netlify. In this posting, we will learn how to continuously deploy this application(both the server and client) to Heroku only with Travis CI. The difficulty here is, our source files of server and client are in the same GitHub repository.

1.1 Deployment Target

Use Travis-CI to continuously deploy the full stack app from GitHub to cloud service Heroku. There are two parts of this app.

  • ’./src/server’, backend, built with Node.js + Express
  • ’./src/client’, frontend, built with React

Our target is to use the same GitHub repository to deploy both the client and server.

  • Deploy backend RESTful API to Heroku, which will be hosted via node src/server/index.js.
  • Deploy frontend React App to Heroku, which will be hosted via node server.js.

2. Full Stack Project

2.1 Source Files

Download the source files for this full stack app. Create your own repository on GitHub and submit this project.

git clone https://github.com/jojozhuang/code-editor-react.git

2.2 Engine

In ‘package.json’, add nodejs and npm version.

"engines": {
  "node": "9.4.0",
  "npm": "6.9.0"

2.3 Procfile

Heroku apps include a Procfile that specifies the commands that are executed by the app on startup. If there is no such file, Heroku will run npm start by default. The following setting tells Heroku to start the application with the given command, which will be running the server in our case.

web: node src/server/index.js

2.4 Server for React

Create a server with express to host react, the client app.

// server.js
const express = require('express');
const path = require('path');

const app = express();
const port = process.env.PORT || 12090;

// Run the app by serving the static files in the dist directory
app.use(express.static(`${__dirname  }/dist`));

// If an incoming request uses a protocol other than HTTPS, redirect that request to the same url but with HTTPS
const forceSSL = function () {
  return function (req, res, next) {
    if (req.headers['x-forwarded-proto'] !== 'https') {
      return res.redirect(['https://', req.get('Host'), req.url].join(''));

// For all GET requests, send back index.html so that PathLocationStrategy can be used
app.get('/*', (req, res) => {
  res.sendFile(path.join(__dirname + '/dist/index.html'));

// Instruct the app to use the forceSSL middleware

// Start the app by listening on the default Heroku port
app.listen(port, () => {
  console.log('Server is up and running at http://localhost:' + port + '/');

2.5 Travis Config File

In the root folder of the project, create a file named ‘.travis.yml’. I configured two providers, one is for server, another is for client. Use after_deploy event to run a bash script.

language: node_js
  - "9"
sudo: true

  - master

  # deploy app as api server
  - provider: heroku
    skip_cleanup: true
      secure: $HEROKU_API_KEY
    app: code-editor-api
  # deploy app as front end website
  - provider: heroku
    skip_cleanup: true
      secure: $HEROKU_API_KEY
    app: code-editor-react

# change settings in Procfile for client
# web: node src/server/index.js
# web: node server.js
- bash ./procfile_upd.sh

Details of the above configuration:

  • First, Travis compiles the whole project and put the output files to directory ‘/home/travis/build/jojozhuang/code-editor-react’. You can get the full path through environment variable TRAVIS_BUILD_DIR.
  • Then, Travis deploys the same output files to different apps configured in deploy event. In our case, we have two apps code-editor-api and code-editor-react.
  • When code-editor-api is deployed, the content in Procfile is still ‘web: node src/server/index.js’, which tells app code-editor-api to start the api server.
  • after_deploy event is fired each time after build is deployed for each provider. In our case, the content in Procfile is updated to ‘web: node server.js’ after code-editor-api is deployed.
  • When code-editor-react is deployed, the content in Procfile is ‘web: node server.js’, which tells app code-editor-react to start the react client.

2.6 Bash Script File

Create a file named procfile_upd.sh as follows. This bash script is used to update Procfile to make the deployed app to launch the client.

# Update Procfile from web: node src/server/index.js -> web: node server.js
rm Procfile
touch Procfile
echo 'web: node server.js' > Procfile

3. Heroku

3.1 Create App for Server

Login to Heroku https://www.heroku.com/, go to Dashboard -> New -> Create new app. Set app name ‘code-editor-api’, click ‘Create app’ button. image

3.2 Create App for Client

Create another app with name ‘code-editor-react’ for hosting React app. image

3.3 Heroku API Key

Go to ‘Account settings’, copy the ‘API Key’. We will use it to setup continuous integration on Travis. image

4. Travis

Login to https://travis-ci.com/, then go to ‘Profile’, click ‘Manage repositories on GitHub’ and add ‘code-editor-react’. image Click the ‘Settings’ of the new repository. Keep the default settings for ‘General’ and ‘Auto Cancellation’. image In the ‘Environment Variables’ section, paste your Heroku API Key in the field ‘Value’ and name it ‘HEROKU_API_KEY’, click ‘Add’ button. image

5. Deployment

5.1 Triggering Build

Make any change to this app and submit it to Github. Once Travis notice the new submission, it starts to build the app according to the instructions configured in ‘.travis.yml’ file. image If the build is finished successfully, the whole site(server + client) is deployed to Heroku. image

5.2 Testing Server

Go to Heroku, you should see the new app ‘code-editor-api’ in the dashboard. image Click on it, and switch to ‘Setting’ tab. You should find the link, it is the root url of the RESTful API. image Access https://code-editor-api.herokuapp.com/api/file/java in browser, we see it returns data. image

5.3 Testing Client

Access https://code-editor-react.herokuapp.com/, we see the homepage. image Click ‘Code Editor’ button, select javascript and click Run. It works properly. image Though chrome debug tool, we see this React app is calling the RESTful API hosted on Heroku to fetch data. image

6. References