DockFlow

Overview

DockFlow is a Node.js script that streamlines Docker image operations, such as building, caching, and publishing. It's designed to simplify Docker image management, making it an invaluable tool for developers and DevOps engineers. DockFlow centralizes all necessary information for Docker image publication in a single dockflow.json file, with the option to use details directly from package.json.

Features

• Builds Docker images without needing to specify the image name.
• Automatically tags images with the correct version.
• Simple and clear command-line arguments for ease of use.
• Facilitates easy publication of images to specified registries.
• Enables the passing of build-specific details such as version as an environment variable to the Docker container.

Prerequisites

• Node.js installed on your machine.
• Access to a Docker environment.
• Properly formatted dockflow.json and/or package.json files in your project directory.

dockflow.json Format

Ensure your dockflow.json file is properly configured. If certain parameters are not provided, the script defaults to values from package.json.

{
  "image": "<optional: defaults to package.json name>",
  "registry": "<optional> will publish the image on the public docker hub if not specified",
  "version": "<optional: defaults to package.json version>",
  "dockerfile": "<optional: defaults to 'Dockerfile'>"
}

Installation

Install DockFlow using npm:

npm install dockflow

Usage

Navigate to your project directory and run DockFlow commands using Node.js. The script recognizes the following commands:

npx dockflow build            // Build Docker image
npx dockflow publish          // Publish Docker image

Building Docker Images

To build a Docker image:

npx dockflow build

The image name is optional and defaults to the name specified in package.json. During the build, you can pass the version dynamically which will be available as an environment variable BUILD_VERSION inside the container:

docker build --build-arg BUILD_VERSION=$(require('../dockflow.json').version || 'latest') ...

To ensure the BUILD_VERSION environment variable is set inside your Docker container, your Dockerfile must include:

ARG BUILD_VERSION
ENV BUILD_VERSION=$BUILD_VERSION

Publishing Docker Images

To publish a Docker image:

npx dockflow publish

The script will use the registry and version details from dockflow.json, defaulting to package.json if not specified.

Additional Tips

When using the dockflow.json as a source for the image, you can display the version of the image directly in the service log for traceability:

console.log("Docker image version: " + (require('../dockflow.json').version || "latest"));

For the build task, you can add parameters, and it will append the image name automatically:

npx dockflow build --no-cache --progress=plain

to publish on npm

npm login npm publish