probot/docs/development.md

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docs/webhooks.md

Developing an App

To develop a Probot app, you will first need a recent version of Node.js installed. Open a terminal and run node -v to verify that it is installed and is at least 8.3.0 or later. Otherwise, install the latest version.

Generating a new app

create-probot-app is the best way to start building a new app. It will generate a new app with everything you need to get started and run your app in production.

To get started, run one of these commands:

• If you're using npm: $ npx create-probot-app my-first-app
• or, if you're using Yarn: $ yarn create probot-app my-first-app

This will ask you a series of questions about your app, which should look something like this:

Let's create a Probot app!
? App name: my-first-app
? Description of app: A "Hello World" GitHub App built with Probot
? Author's full name: Katie Horne
? Author's email address: katie@auth0.com
? Homepage:
? GitHub user or org name: khorne3
? Repository name: my-first-app
created file: my-first-app/.env.example
created file: my-first-app/.gitignore
created file: my-first-app/.travis.yml
created file: my-first-app/LICENSE
created file: my-first-app/README.md
created file: my-first-app/app.json
created file: my-first-app/index.js
created file: my-first-app/package-lock.json
created file: my-first-app/package.json
created file: my-first-app/docs/deploy.md
Finished scaffolding files!

Installing Node dependencies!

Done! Enjoy building your Probot app!

The most important files note here are index.js, which is where the code for your app will go, and package.json, which makes this a standard npm module.

Configure a GitHub App

To run your app in development, you will need to configure a GitHub App to deliver webhooks to your local machine.

1. On your local machine, copy .env.example to .env.
2. Go to smee.io and click Start a new channel. Set WEBHOOK_PROXY_URL in .env to the URL that you are redirected to.
3. Create a new GitHub App with:
   • Webhook URL: Use your WEBHOOK_PROXY_URL from the previous step.
   • Webhook Secret: development
   • Permissions & events is located lower down the page and will depend on what data you want your app to have access to. Note: if, for example, you only enable issue events, you will not be able to listen on pull request webhooks with your app. However, for development we recommend enabling everything.
4. Download the private key and move it to your project's directory. It will get picked up by Probot automatically.
5. Edit .env and set APP_ID to the ID of the app you just created. The App ID can be found in your app settings page here
6. Run $ npm start to start the server/

You'll need to create a test repository and install your app by clicking the "Install" button on the settings page of your app.

Running the app

Once you've set the APP_ID of your GitHub app in .env and downloaded the private key, you're ready to run your app.

$ npm start
> probot run ./index.js

Yay, the plugin was loaded!
18:11:55.838Z DEBUG Probot: Loaded plugin: ./index.js

Optionally, you can also run your app through nodemon which will listen on any files changes in your local development environment and automatically restart the server. After installing nodemon, you can run nodemon --exec "npm start" and from there the server will automatically restart upon file changes.

Debugging

1. Always run $ npm install and restart the server if package.json has changed.
2. To turn on verbose logging, start server by running: $ LOG_LEVEL=trace npm start