This is a very simple GitHub action that allows you to deploy to Heroku. The action works by running the following commands in shell via NodeJS:-

1. Getting Started
2. Options
3. Examples
   • Deploy with Docker
   • Deploy with custom Buildpacks
   • Deploy Subdirectory
   • Deploy Custom Branch
4. Health Check
5. Environment Variables
6. Procfile Passing
7. Important Notes
8. License

To get started using the action, just make sure to have a Procfile or a Dockerfile in your project and then create a folder called .github and inside it, create another folder called workflows. Finally inside the workflows folder, create a file called main.yml with the following contents:

.github/workflows/main.yml

name: Deploy

on:
  push:
    branches:
      - master

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: akhileshns/heroku-deploy@v3.3.6 # This is the action
        with:
          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
          heroku_app_name: "YOUR APP's NAME" #Must be unique in Heroku
          heroku_email: "YOUR EMAIL"

Now go to your Heroku account and go to Account Settings. Scroll to the bottom until you see API Key. Copy this key and go to your project's repository on GitHub.

In your Repo, go to Settings -> Secrets and click on "New Secret". Then enter HEROKU_API_KEY as the name and paste the copied API Key as the value.

You can now push your project to GitHub and it will be automatically deployed to Heroku henceforth.

You learn more about GitHub Secrets here and GitHub Actions here

The action comes with additional options that you can use to configure your project's behavior on Heroku. You can setup these options under the "with" object as presented above:

Heroku now allows users to deploy docker containers. To use this feature, simply add a Dockerfile to your project and add a CMD command at the end of the Dockerfile. This is the command used by heroku to start the webserver inside the container. Finally make sure to set the usedocker flag to true before deploying.

.github/workflows/main.yml

name: Deploy

on:
  push:
    branches:
      - master

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: akhileshns/heroku-deploy@v3.3.6 # This is the action
        with:
          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
          heroku_app_name: "YOUR APP's NAME" #Must be unique in Heroku
          heroku_email: "YOUR EMAIL"
          usedocker: true

P.S: Keep in mind that if you deploy once using docker, the same heroku app is not compatible with a non-docker setup and similarly, you cannot deploy a dockerized setup to a non-docker heroku app.

Also thanks to Olav Sundfør for adding this feature

Taken from the official heroku website:

"Heroku Buildpacks are sets of open source scripts that are used for compiling apps on Heroku. They form the backbone of Heroku’s polyglot platform. Buildpacks enable you to extend Heroku's build system to support your language or customizations, or to make particular binary packages available to the runtime. Heroku Buildpacks give you the freedom to code in the languages and frameworks that work best for your app and your team"

To use a custom buildpack in the action, simply add the url of the buildpack to the action:

.github/workflows/main.yml

name: Deploy

on:
  push:
    branches:
      - master

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: akhileshns/heroku-deploy@v3.3.6 # This is the action
        with:
          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
          heroku_app_name: "YOUR APP's NAME" #Must be unique in Heroku
          heroku_email: "YOUR EMAIL"
          buildpack: "https://github.com/HashNuke/heroku-buildpack-elixir.git"

If you are using a complex application which has both frontend and backend applications in separate folders, you can specify a path to the directory to deploy using the appdir option:

.github/workflows/main.yml

name: Deploy

on:
  push:
    branches:
      - master

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: akhileshns/heroku-deploy@v3.3.6 # This is the action
        with:
          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
          heroku_app_name: "YOUR APP's NAME" #Must be unique in Heroku
          heroku_email: "YOUR EMAIL"
          appdir: "api" # <- This will point to the api folder in your project

Thanks to meszarosdezso for adding the appdir feature

You can use the branch option to deploy an app in another branch

.github/workflows/main.yml

name: Deploy

on:
  push:
    branches:
      - master # Changing the branch here would also work

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: akhileshns/heroku-deploy@v3.3.6 # This is the action
        with:
          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
          heroku_app_name: "YOUR APP's NAME" #Must be unique in Heroku
          heroku_email: "YOUR EMAIL"
          branch: "dev"

Though this is also possible to do with GitHub Actions, click here for more information

Sometimes you will run into issues where the action has successfully deployed the project but because of some error in code or the like, the Heroku App crashes or fails to launch. To counter this, you can setup a healthcheck in the action:

.github/workflows/main.yml

name: Deploy

on:
  push:
    branches:
      - master # Changing the branch here would also work

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: akhileshns/heroku-deploy@v3.3.6 # This is the action
        with:
          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
          heroku_app_name: "YOUR APP's NAME" #Must be unique in Heroku
          heroku_email: "YOUR EMAIL"
          healthcheck: "https://[YOUR APP's NAME].herokuapp.com/health"

Adding the url to the healthcheck option of the action will make the action attempt to perform a GET Request to that url and print the response if successful. Else it will fail the action to indicate that the deploy was not successful.

P.S: It is recommended that you setup a specific route such as /health for performing healthchecks

Additionally, if you are using a custom route for performing healthchecks, you can check for a specific value from this url using the checkstring option of the action like so:

.github/workflows/main.yml

name: Deploy

on:
  push:
    branches:
      - master # Changing the branch here would also work

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: akhileshns/heroku-deploy@v3.3.6 # This is the action
        with:
          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
          heroku_app_name: "YOUR APP's NAME" #Must be unique in Heroku
          heroku_email: "YOUR EMAIL"
          healthcheck: "https://[YOUR APP's NAME].herokuapp.com/health"
          checkstring: "ok"

This will essentially check if the value returned by sending a GET request to the healthcheck url is equal to the checkstring

In some cases, a healthcheck ends up being performed before the application has been setup on Heroku. To counter this, you can manually set the delay option in the action to make the action wait a certain period of time (in seconds) before performing the healthcheck

.github/workflows/main.yml

name: Deploy

on:
  push:
    branches:
      - master # Changing the branch here would also work

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: akhileshns/heroku-deploy@v3.3.6 # This is the action
        with:
          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
          heroku_app_name: "YOUR APP's NAME" #Must be unique in Heroku
          heroku_email: "YOUR EMAIL"
          healthcheck: "https://[YOUR APP's NAME].herokuapp.com/health"
          checkstring: "ok"
          delay: 5

By default, the delay will be 0 if you choose to not set it

Heroku offers a means of passing sensitive information to your app (such as api keys etc) via something it calls config vars which you can find in the settings of your heroku app. But sometimes you might want to store sensitive information (api keys etc) in GitHub Secrets instead just to ensure platform independence. If you choose to this, you can then pass those secrets to your heroku app by using the "env" object of the action:-

.github/workflows/main.yml

name: Deploy

on:
  push:
    branches:
      - master # Changing the branch here would also work

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: akhileshns/heroku-deploy@v3.3.6 # This is the action
        with:
          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
          heroku_app_name: "YOUR APP's NAME" #Must be unique in Heroku
          heroku_email: "YOUR EMAIL"
        env:
          HD_FIREBASE_API_KEY: ${{secrets.FIREBASE_API_KEY}}
          HD_RANDOM_DATA: "Hello"

Note that the variables must start with "HD_". This is is important so the action can tell your environment variable apart from multiple other variables (passed by your language, github actions etc) which you probably don't want sitting in your heroku app's config vars.

On that note, if you've set these variables and have deployed your app, you can check your Heroku App's config vars and you'll find that they have been set with the env variables you have passed.

PLEASE NOTE: The "HD_" will be scrapped from the variable your name by the action. So in your project, "FIREBASE_API_KEY" will be passed instead of "HD_FIREBASE_API_KEY" (for example) and you can see this if you check your Heroku App's config vars. We understand that this can be confusing but this is again to ensure Platform independence and so that you don't have to use HD_FIREBASE_API_KEY if you choose to stop using Heroku

In some cases, you might want to be able to set the Procfile within the action itself instead of declaring it manually in your project. Although this approach is not recommended in favor of just using multiple branches, it might still be useful in some edge cases. You can set the Procfile in the action by using the procfile option of the action like so:

.github/workflows/main.yml

name: Deploy

on:
  push:
    branches:
      - master # Changing the branch here would also work

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: akhileshns/heroku-deploy@v3.3.6 # This is the action
        with:
          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
          heroku_app_name: "YOUR APP's NAME" #Must be unique in Heroku
          heroku_email: "YOUR EMAIL"
          procfile: "web: npm start"

Keep in mind this won't work if you are using Docker.

• You can check this repo's .github/workflows/main.yml for example use cases of the action in use. Additionally the APIs for these use cases can be found in the tests folder of the repo

• You can find the secrets tab in your project's settings

• Be careful with your appname, cuz the action either deploys to an existing app or creates a new one if it doesn't exist. So if you accidently change it after deploying it once already, the action won't fail, it'll just create a new dyno and if you are on a paid plan, heroku can be expensive. On that note, always check the logs of your actions to make sure everything is A-OK.

• If you're using the above exact workflow code, keep in mind that it deploys whenever you make a change to the master branch (Even README updates which have nothing to do with application code) and that might not be very efficient for you, have a look through the github actions docs to customize when the action should trigger.

  (I would recommend making a separate dev branch and setting up the action to trigger upon pull request to the master branch)

• By default, if you don't specify a branch in your action, it will default to the HEAD branch (or whichever branch the action is defined under). So you might be wondering what happens if you define the same action in a different branch under the same heroku app name (or which you try to deploy to the same appname from a different branch)? The answer is that the new branch overrides whatever your old branch was (even if the new branch is behind the old branch in terms of commits unless you set dontuseforce to true)

• For more info on how Heroku enables deployment using Docker, check out https://www.heroku.com/deploy-with-docker

This project is licensed under the MIT License - see the LICENSE file for details