@octokit/webhooks

GitHub webhook events toolset for Node.js

• Usage
• Local development
• API
  • Constructor
  • webhooks.sign()
  • webhooks.verify()
  • webhooks.verifyAndReceive()
  • webhooks.receive()
  • webhooks.on()
  • webhooks.onAny()
  • webhooks.onError()
  • webhooks.removeListener()
  • webhooks.middleware()
  • Webhook events
• TypeScript
  • EmitterWebhookEventName
  • EmitterWebhookEvent
• License

@octokit/webhooks helps to handle webhook events received from GitHub.

GitHub webhooks can be registered in multiple ways

1. In repository or organization settings on github.com.
2. Using the REST API for repositories or organizations
3. By creating a GitHub App.

Note that while setting a secret is optional on GitHub, it is required to be set in order to use @octokit/webhooks. Content Type must be set to application/json, application/x-www-form-urlencoded is not supported.

Usage

// install with: npm install @octokit/webhooks
const { Webhooks } = require("@octokit/webhooks");
const webhooks = new Webhooks({
  secret: "mysecret",
});

webhooks.onAny(({ id, name, payload }) => {
  console.log(name, "event received");
});

require("http").createServer(webhooks.middleware).listen(3000);
// can now receive webhook events at port 3000

Local development

You can receive webhooks on your local machine or even browser using EventSource and smee.io.

Go to smee.io and Start a new channel. Then copy the "Webhook Proxy URL" and

1. enter it in the GitHub App’s "Webhook URL" input
2. pass it to the EventSource constructor, see below

const webhookProxyUrl = "https://smee.io/IrqK0nopGAOc847"; // replace with your own Webhook Proxy URL
const source = new EventSource(webhookProxyUrl);
source.onmessage = (event) => {
  const webhookEvent = JSON.parse(event.data);
  webhooks
    .verifyAndReceive({
      id: webhookEvent["x-request-id"],
      name: webhookEvent["x-github-event"],
      signature: webhookEvent["x-hub-signature"],
      payload: webhookEvent.body,
    })
    .catch(console.error);
};

EventSource is a native browser API and can be polyfilled for browsers that don’t support it. In node, you can use the eventsource package: install with npm install eventsource, then const EventSource = require('eventsource')

API

1. Constructor
2. webhooks.sign()
3. webhooks.verify()
4. webhooks.verifyAndReceive()
5. webhooks.receive()
6. webhooks.on()
7. webhooks.onAny()
8. webhooks.onError()
9. webhooks.removeListener()
10. webhooks.middleware()
11. Webhook events

Constructor

new Webhooks({secret[, path, transform]})

Returns the webhooks API.

webhooks.sign()

webhooks.sign(eventPayload);

Returns a signature string. Throws error if eventPayload is not passed.

Can also be used standalone.

webhooks.verify()

webhooks.verify(eventPayload, signature);

Returns true or false. Throws error if eventPayload or signature not passed.

Can also be used standalone.

webhooks.verifyAndReceive()

webhooks.verifyAndReceive({ id, name, payload, signature });

Returns a promise.

Verifies event using webhooks.verify(), then handles the event using webhooks.receive().

Additionally, if verification fails, rejects the returned promise and emits an error event.

Example

const { Webhooks } = require("@octokit/webhooks");
const webhooks = new Webhooks({
  secret: "mysecret",
});
eventHandler.on("error", handleSignatureVerificationError);

// put this inside your webhooks route handler
eventHandler
  .verifyAndReceive({
    id: request.headers["x-github-delivery"],
    name: request.headers["x-github-event"],
    payload: request.body,
    signature: request.headers["x-hub-signature"],
  })
  .catch(handleErrorsFromHooks);

webhooks.receive()

webhooks.receive({ id, name, payload });

Returns a promise. Runs all handlers set with webhooks.on() in parallel and waits for them to finish. If one of the handlers rejects or throws an error, then webhooks.receive() rejects. The returned error has an .errors property which holds an array of all errors caught from the handlers. If no errors occur, webhooks.receive() resolves without passing any value.

The .receive() method belongs to the event-handler module which can be used standalone.

webhooks.on()

webhooks.on(eventName, handler);
webhooks.on(eventNames, handler);

The .on() method belongs to the event-handler module which can be used standalone.

webhooks.onAny()

webhooks.onAny(handler);

The .onAny() method belongs to the event-handler module which can be used standalone.

webhooks.onError()

webhooks.onError(handler);

If a webhook event handler throws an error or returns a promise that rejects, an error event is triggered. You can use this handler for logging or reporting events. The passed error object has a .event property which has all information on the event.

Asynchronous error event handler are not blocking the .receive() method from completing.

The .onError() method belongs to the event-handler module which can be used standalone.

webhooks.removeListener()

webhooks.removeListener(eventName, handler);
webhooks.removeListener(eventNames, handler);

The .removeListener() method belongs to the event-handler module which can be used standalone.

webhooks.middleware()

webhooks.middleware(request, response[, next])

Returns a requestListener (or middleware) method which can be directly passed to http.createServer(), Express and other compatible Node.js server frameworks.

Can also be used standalone.

Webhook events

See the full list of event types with example payloads.

If there are actions for a webhook, events are emitted for both, the webhook name as well as a combination of the webhook name and the action, e.g. installation and installation.created.

TypeScript

The types for the webhook payloads are sourced from @octokit/webhooks-definitions, which can be used by themselves.

In addition to these types, @octokit/webhooks exports 2 types specific to itself:

Note that changes to the exported types are not considered breaking changes, as the changes will not impact production code, but only fail locally or during CI at build time.

EmitterWebhookEventName

A union of all possible events supported by the event emitter.

EmitterWebhookEvent

The object that is emitted by @octokit/webhooks as an event; made up of an id, name, and payload properties. An optional generic parameter can be passed to narrow the type of the payload property to be based on the name of the event.

License

MIT