git-webhook-receiver

README

git webhook receiver

A small service that listens for incoming webhook HTTP POST requests from a Git provider (Gitea, GitHub, GitLab) for one or more projects and runs a given script in response to matching webhook events.

Its intended use is to run CI/CD scripts on a server, but it can be used to execute arbitrary actions on Git events.

In a nutshell:

• Seploy it to your server.
• (Optional but recommended) Install an SSL certificate or wrap it with a reverse proxy, such as Nginx or Caddy, to enable encryption.
• Create a config file and add your projects along with their corresponding build scripts/actions, either as standalone scripts or cross-platform inline scripts
• set webhooks for those repo in their git services (Github, Gitea, Gitlab, etc.) to post to {YOUR_HOST}/projects/{PROJECT_NAME}
• Start the service. It will listen for the webhook posts and execute the actions described in the config (e.g., building your projects or other tasks) when the webhooks are triggered by Git.

WIP, but operational. Some planned MVP functionality is still missing and there will be breaking changes before version 1.0 release.

Config file

The app requires a config file to start. By default, the config file is read from ./config.yml. You can override this behavior by setting CONFIG_PATH env variable or by using --config flag when launching the app (the flag takes precedence).

A typical config file may look like this:

host: example.com
ssl:
  cert_file_path: "./your/certfile/path/fullchain.pem"
  key_file_path: "/your/keyfile/path/privkey.pem"
projects:
  my_awesome_roject:
    repo: "username/reponame"
    secret: "YourSecretGoesHere"
    actions:
      - on: push
        branch: main
        user: www-data
        cwd: "/var/www/default"
        script: |
          git fetch && git reset --hard origin/main
          npm ci
          npm run build
  my_other_project:
    repo: "username/reponame2"
    secret: "YourSecretGoesHere"
    actions:
      - cwd: "/var/www/backend" # Anything besides `script` or `run` is optional
        run: ["sh", "./build.sh"]

Please refer to the config file example in this repo, to see a list of all available configuration options.

For security reason, it's recommended to always provide a secret or at least authorization param (in case of Gitea or Gitlab providers) for every action. The secret also protects against MiM attacks, ensuring that the payload hasn't been tampered with.

Gitlab currently doesn't sign its requests, so only authorization is availabe for gitlab receivers, while Github only supports request signature and not authorization headers, so only secret for Github receivers. Gitea supports both authorization and signature verification.

Most of the config values can be provided via ENV variables. Please consider if it makes sense for your application to provide secrets in this manner.

Installation

Build from source

To build the app, you need go version 1.22 or higher. Since the app stores action outputs and logs in an SQLite3 database via go-sqlite3 you also need a gcc compiler installed on your system and have CGO_ENABLED=1 env variable set.

go install github.com/religiosa1/git-webhook-receiver@latest

Or you can clone the repo, and run the following command in its root dir:

go build

Please refer to the docs/systemd-init-script.md for an example of a system.d script, that can be used to launch the service at startup.

SSL

It’s recommended to use SSL so that your requests are encrypted. If you have an HTTP server such as Nginx or Caddy, you can use it to provide a reverse proxy with SSL support.

Infortmation on how to configure nginx + certbot can be found here.

If you don’t have an HTTP server available, you can use the internal SSL functionality by providing the certificate and key files in the corresponding config fields.

Inline scripts and standalone scripts

Inline scripts are processed using the mdvan/sh interpreter to ensure they are cross-platform (in other words, they work on Windows). These scripts are intended to be simple one- or multi-line bash-like commands, such as "clone and run the build task."

Example:

script: |
  git fetch && git reset --hard origin/master
  npm ci
  npm run build

If you need something more complicated, it's probably better to use run field instead of script in the action config, passing a standalone script to it (bash, Python, or any other language supported by your system). The run field accepts its parameters in exec form, as an array of argv strings, in the same way as docker's CMD does:

Example:

run: ["python", "./path/to/your/script", "--some-arg"]

In any case, you can optionally supply the cwd param, to specify the root dir for execution and on unix-like systems user param,to specify the user who will run the script.

Please notice, that user param is not supported on windows and your script will always run from the same user, that launches the service.

Inspection HTTP API

By default, the app exposes inspection HTTP endpoints, unless disable_api: true is set in the config. These endpoints allows you to get the status/output of a pipeline, list pipelines, or view the app logs.

GET /pipelines/{:pipeId} # To see the pipeline status
GET /pipelines/{:pipeId}/output # To see the pipe output
GET /pipelines # To list last pipelines
GET /logs # To see the logs result

You can find the full documentation for endpoints and params they accept here

You can also enable BasicAuth for the APi either in the config:

api_password: "mysecret"

or with a env variable API_PASSWORD=mysecret

Security Warning: Do not use BasicAuth unless SSL is enabled (either in the app or via a reverse proxy), as your credentials can sniffed.

CLI

In addition to the default serve mode, the app provides a couple of CLI subcommands to retrieve logs, inspect pipeline results, and retrieve their output. It duplicates the HTTP-API functionality for the local access or cases when HTTP-API is disabled.

Run git-webhook-receiver --help to see the list of available subcomands or run git-webhook-receiver <SUBCOMMAND> --help to subcommand's help.

Some examples:

You can use pipeline subcommand to check the last or given pipeline:

git-webhook-receiever pipeline # shows the last pipeline
# OR
git-webhook-receiever pipeline <PIPE_ID>

Run get-webhook-receiver ls to see a list of the last N pipelines. Run get-webhook-receiver logs to inspect app logs.

Logging

By default, action outputs and logs are stored persistently in two SQLite databases: one for app logs and one for actions and their outputt. By default, actions db filename is actions.sqlite3, logs db filename is logs.sqlite3. This filenames are controlled by the actions_db_file and logs_db_file fields in the config correspondingly.

Setting those config values to an empty string will disable the persistent on storage of this information and in turn will also disable the corresponding HTTP-API and/or CLI subcommands.

Actions' output is stored in the db once the action is completed. While the action is still in progress, data is stored in a temporary file.

Both databases use Write-Ahead Logging. This means, in addition to the file specified in the config, the app will also create two additional temporary files during operation <YOUR_FILE>-wal and <YOUR_FILE>-shm, to ensure data ingtegrity during write operations.

Contribution

If you have any ideas or suggestions or want to report a bug, feel free to write in the issues section or create a PR.

License

git-webhook-reciever is MIT licensed.