Seel NPM | npm.io

seel

seel is a command-line tool that facilitates the build of container image for your Node.js applications. You don't need to master container best practices or write a Dockerfile to build a container image, it's just as simple as invoking a command from your shell or npm script.

screencast

Install

npm

$ npx seel                      # Run it once.
$ npm install --global seel     # Install globally.
$ npm install --save-dev seel   # Install locally to use it in npm scripts.

yarn

$ yarn global add seel          # Install globally.
$ yarn add seel --dev           # Install locally to use it in npm scripts.

Usage

seel uses the Docker daemon to build the container image for your Node.js application. When you invoke the seel command, the Docker daemon must be running and accessible through the /var/run/docker.sock socket.

CLI

Options

Name	Description
‑v, ‑‑version	Print version.
‑h, ‑‑help	Print usage information.
‑‑cwd	Define the current working directory, defaults to `.`.
‑‑entrypoint	Define the app entrypoint, defaults to `bin` or `main` script defined in `package.json`. The given `path` must be relative to the cwd.
‑‑extra‑files	Define the extra files to include in the container image with a glob pattern, e.g. `--extra-files 'public/**'`.
‑‑label	Define the container image label, e.g. `--label key=value --label key2=value2`. By default, the `version`, `description` and `maintainer` labels are added to the container image.
‑‑name	Define the container image name, defaults to the app `name` defined in `package.json`.
‑‑pkg‑registry‑auth‑url	Set-up authentication for the given package registry base URL, e.g. `https://myregistry.example.com`. If the authentication token is not defined with `‑‑pkg‑registry‑auth‑token` the environment variable `AUTH_TOKEN` will be used to read the authentication token.
‑‑pkg‑registry‑auth‑token	Define the authentication token for the package registry base URL previously configured.
‑‑port	Define the port that the container exposes at runtime, e.g. `--port 3000 --port 4000/udp`.
‑‑tag	Define the container image tag, e.g. `--tag latest --tag 1.0.0`. By default, the Semantic Versioning strategy is used to define the container image tags.

API

import { buildImage, BuildImageOptions } from "seel";

const options: BuildImageOptions = {
  entrypoint?: string;
  extraFiles?: string[];
  name?: string;
  ports?: string[];
  tags?: string[];
  labels?: {
    [key: string]: string
  };
  pkgRegistryAuth?: {
    url: string;
    token: string
  };
};

buildImage("/usr/app", options)
  .then(stream => stream
    .once("error", () => {
      console.log(err);
      process.exit(1);
    })
    .pipe(process.stdout)
  )
  .catch(err => {
    console.log(err);
    process.exit(2);
  });

Examples

cli - A command-line app that outputs Hello, World! or greets the name passed as an argument.
express - An Express app that responds {"message":"Hello, World!"} to HTTP GET / requests or greets the name passed as query param.
express-static - An Express app that serves the static files stored in the public directory.