msz/oneshot

🔫 simple webhook receiver for launching a shell command

oneshot

a minimal, no dependency webhook server for launching a shell command, written in pure Node

Features

• receives your webhook
• runs your command
• supports the GitHub webhook authentication scheme out of the box
• doesn't break when leftpad is unpublished

Installation & running

oneshot works great with Docker:

$ docker run --publish "8080:80" \
             --detach \
             michalszewczak/oneshot

Alternatively, you can always clone this repo and do:

ONESHOT_PORT=8080 npm start

This requires Node 8 or higher. An npm package installation option might also be available soon.

Now let's POST:

$ curl --data '' localhost:8080
{
  "errorCode": 0,
  "stdout": "Hello from a oneshot webhook!\n",
  "stderr": ""
}

To specify the command to run, set the ONESHOT_COMMAND environment variable:

$ docker run --publish "8080:80" \
             --env ONESHOT_COMMAND="echo \"My custom command!\"" \
             --detach \
             michalszewczak/oneshot

$ curl --data '' localhost:8080
{
  "errorCode": 0,
  "stdout": "My custom command!\n",
  "stderr": ""
}

In most cases, you'll want to extend the oneshot Docker image and install some software for oneshot to run. Check out https://github.com/msz/blog-stack for an example of specialized oneshot servers.

Configuration

Configure oneshot through environment variables.

ONESHOT_PORT - The port which oneshot listens on. Default: 80

ONESHOT_COMMAND - The command to execute. A simple echo command by default.

ONESHOT_AUTH - The authorization scheme to apply. Valid values:

• none - (default) No authorization. oneshot will execute the command upon receiving the POST request.
• github - Uses the GitHub webhook authorization scheme. Set the secret in the ONESHOT_AUTH_KEY environment variable.

ONESHOT_AUTH_KEY - The authorization key to use. See ONESHOT_AUTH.