@codedependant/semantic-release-docker

A semantic-release plugin to use semantic versioning for docker images.

Supported Steps

verifyConditions

verifies that environment variables for authentication via username and password are set. It uses a registry server provided via config or environment variable (preferred) or defaults to docker hub if none is given. It also verifies that the credentials are correct by logging in to the given registry.

prepare

builds a an image using the specified docker file and context. This image will be used to create tags in later steps

publish

pushes the tags Images with specified tags and pushes them to the registry. Tags support simple templating via handlebars. Values enclosed in braces {{}} will be substituted with release context information

Installation

Run npm i --save-dev @codedependant/semantic-release-docker to install this semantic-release plugin.

Configuration

Docker registry authentication

Authentication to a docker registry is set via environment variables. It is not required, and if omitted, it is assumed the docker daemon is already authenticated with the target registry.

Environment variables

Variable	Description
DOCKER_REGISTRY_USER	The user name to authenticate with at the registry.
DOCKER_REGISTRY_PASSWORD	The password used for authentication at the registry.

Options

Option	Description	Type	Default
dockerTags	Optional. An array of strings allowing to specify additional tags to apply to the image. Supports templating	Array<String>	[latest, {{major}}-latest, {{version}}]
dockerImage	Optional. The name of the image to release.	String	Parsed from package.json name property
dockerRegistry	Optional. The hostname and port used by the the registry in format hostname[:port]. Omit the port if the registry uses the default port	String	null (dockerhub)
dockerProject	Optional. The project or repository name to publish the image to	String	For scoped packages, the scope will be used, otherwise null
dockerPlatform	Optional. A list of target platofmrs to build for. If specified, buildx Will be used to generate the final images	Array<String>	null (default docker build behavior)
dockerFile	Optional. The path, relative to $PWD to a Docker file to build the target image with	String	Dockerfile
dockerContext	Optional. A path, relative to $PWD to use as the build context A	String	.
dockerLogin	Optional. Set to false it by pass docker login if the docker daemon is already authorized	String	true
dockerArgs	Optional. Include additional values for docker's build-arg. Supports templating	Object
dockerPublish	Optional. Automatically push image tags during the publish phase.	Boolean	true
dockerVerifyCmd	Optional. If specified, during the verify stage, the specified command will execute in a container of the build image. If the command errors, the release will fail.	String	false
dockerNetwork	Optional. Specify the Docker network to use while the image is building.	String	default
dockerAutoClean	Optional. If set to true	Boolean	true
dockerBuildFlags	Optional. An object containing additional flags to the docker build command. Values can be strings or an array of strings	Object	{}
dockerBuildCacheFrom	Optional. A list of external cache sources. See --cache-from	String | Array<String>

BuildX Support

Version 5.X includes initial and experimental support for multi-platform images via the buildx plugin. This plugin assumes that the docker daemon and buildx have already been setup correctly. Platform specific builder must be setup and selected for this plugin to utilize buildx

Warning

When using buildx via the dockerPlatform option, images are not kept locally and normal docker commands targeting those images will not work. The dockerVerifyCmd behavior will only trigger a build and is unable to execute local command

Build Arguments

By default several build arguments will be included when the docker images is being built. Build arguments can be templated in the same fashion as docker tags. If the value for a build argument is explicitly true, the value will be omitted and the value from a matching environment variable will be utilized instead. This can be useful when trying to include secrets and other sensitive information

Argument Name	Description	Default
SRC_DIRECTORY	The of the directory the build was triggered from	The directory name of CWD
TARGET_PATH	Path relative to the execution root. Useful for Sharing a Single Docker file in monorepos
NPM_PACKAGE_NAME	The name property extracted from package.json - if present
NPM_PACKAGE_SCOPE	The parsed scope from the name property from package.json - sans @
CONFIG_NAME	The configured name of the docker image.	The parsed package name
CONFIG_PROJECT	The configured docker repo project name	The package scope if present
GIT_SHA	The commit SHA of the current release
GIT_TAG	The git tag of the current release

Template Variables

String template will be passed these

Variable name	Description	Type
git_sha	The commit SHA of the current release	String
git_tag	The git tag of the current release	String
release_type	The severity type of the current build (major, minor, patch)	String
release_notes	The release notes blob associated with the release	String
next	Semver object representing the next release	Object
previous	Semver object representing the previous release	Object
major	The major version of the next release	Number
minor	The minor version of the next release	Number
patch	The patch version of the next release	Number
prerelease	The prerelease versions of the next release	Array<Number>
env	Environment variables that were set at build time	Object
pkg	Values parsed from package.json	Object
build	A Random build hash representing the current execution context	String
now	Current timestamp is ISO 8601 format	String

Template Helpers

The following handlebars template helpers are pre installed

Helper name	Description	Return Type	Example
endswith	returns true if a string ends with another	Boolean	{{#if (endswith myvar 'ing')}}{{ othervar }}{{/if}}
eq	returns true if two values are strictly equal to each other	Boolean	{{#if (eq var_one var_two)}}{{ var_three }}{{/if}}
gt	returns true if the first value is greater than the second	Boolean	{{#if (gt var_one var_two)}}{{ var_three }}{{/if}}
gte	returns true if the first value is greater than or equal to the second	Boolean	{{#if (gte var_one var_two)}}{{ var_three }}{{/if}}
includes	returns true if the input (string | array) includes the second value	Boolean	{{#if (includes some_array 'one')}}{{ var_one }}{{/if}}
lower	returns the lower cased varient of the input string	String	{{ lower my_var }}
lt	returns true if the first value is less than the second	Boolean	{{#if (lt var_one var_two)}}{{ var_three }}{{/if}}
lte	returns true if the first value is less than or equal to the second	Boolean	{{#if (lte var_one var_two)}}{{ var_three }}{{/if}}
neq	returns true if two values are not equal to each other	Boolean	{{#if (neq var_one var_two)}}{{ var_three }}{{/if}}
pick	returns the first non null-ish value. Will treat false as a value	any	{{#with (pick var_one, var_two) as | value |}}{{ value }}{{/with}}
split	splits csv values into a javascript array	Array	{{#each (split csv_value)}}{{ this }}{{/each}}
startswith	returns true if a string starts with another	Boolean	{{#if (starts myvar 'foo')}}{{ othervar }}{{/if}}
upper	returns the upper cased varient of the input string	String	{{upper my_var}}

Build Flags

Using the dockerBuildFlags option allows you to pass arbitrary flags to the build command. If the standardized options are not sufficient, dockerBuildFlags is a perfect workaround until first class support can be added. This is considered and advanced feature, and you should know what you intend to do before using. There is no validation, and any configuration of the docker daemon required is expected to be done before hand.

Keys found in dockerBuildFlags are normalized as command line flags in the following manner:

• If the key does not start with a - it will be prepended
• all occurences of _ will be re-written as -
• Single letter keys are considered shorthands e.g. p becomes -p
• Multi letter keys are considered long form e.g. foo_bar becomes --foo-bar
• If the value is an array, the flag is repeated for each occurance
• A null value may be used to omit the value and only inject the flag itself

Example

{
  plugins: [
    ['@codedependant/semantic-release-docker', {
      dockerImage: 'my-image',
      dockerRegistry: 'quay.io',
      dockerProject: 'codedependant',
      dockerCacheFrom: 'myname/myapp'
      dockerBuildFlags: {
        pull: null
      , target: 'release'
      },
      dockerArgs: {
        GITHUB_TOKEN: null
      }
    }]
  ]
}

This configuration, will generate the following build command

> docker build --network=default --quiet --tag quay.io/codedependant/my-image:abc123 --cache-from myname/myapp --build-arg GITHUB_TOKEN --pull --target release -f path/to/repo/Dockerfile /path/to/repo

Usage

full configuration:

// release.config.js

module.exports = {
  branches: ['main']
  plugins: [
    ['@codedependant/semantic-release-docker', {
      dockerTags: ['latest', '{{version}}', '{{major}}-latest', '{{major}}.{{minor}}'],
      dockerImage: 'my-image',
      dockerFile: 'Dockerfile',
      dockerRegistry: 'quay.io',
      dockerProject: 'codedependant',
      dockerPlatform: ['linux/amd64', 'linux/arm64']
      dockerBuildFlags: {
        pull: null
      , target: 'release'
      },
      dockerArgs: {
        API_TOKEN: null
      , RELEASE_DATE: new Date().toISOString()
      , RELEASE_VERSION: '{{next.version}}'
      }
    }]
  ]
}

results in quay.io/codedependant/my-image with tags latest, 1.0.0, 1-latest and the 1.0 determined by semantic-release.

Alternatively, using global options w/ root configuration

// package.json
{
  "name": "@codedependant/test-project"
  "version": "1.0.0"
  "release": {
    "extends": "@internal/release-config-docker",
    "dockerTags": ["latest", "{{version}}", "{{major}}-latest", "{{major}}.{{minor}}"],
    "dockerImage": "my-image",
    "dockerFile": "Dockerfile",
    "dockerRegistry": "quay.io",
    "dockerArgs": {
      "GITHUB_TOKEN": null
    , "SOME_VALUE": '{{git_sha}}'
    }
  }
}

This would generate the following for a 1.2.0 build

$ docker build -t quay.io/codedependant/my-image --build-arg GITHUB_TOKEN --build-arg SOME_VALUE=6eada70 -f Dockerfile .
$ docker tag <SHA1> latest
$ docker tag <SHA1> 1.2.0
$ docker tag <SHA1> 1.2
$ docker tag <SHA1> 1-latest
$ docker push quay.io/codedependant/my-image

minimum configuration:

{
  "release": {
    "plugins": [
      "@codedependant/semantic-release-docker"
    ]
  }
}

• A package name @codedependant/test-project results in docker project namecodedependant and image name test-project
• A package name test-project results in a docker image name test-project

the default docker image tags for the 1.0.0 release would be 1.0.0, 1-latest, latest

example prerelease configuration:

{
  "release": {
    "dockerTags": [
      "{{#if prerelease.[0]}}{{prerelease.[0]}}{{else}}latest{{/if}}",
      "{{major}}-{{#if prerelease.[0]}}{{prerelease.[0]}}{{else}}latest{{/if}}",
      "{{major}}.{{minor}}-{{#if prerelease.[0]}}{{prerelease.[0]}}{{else}}latest{{/if}}",
      "{{version}}"
    ]
  }
}

the docker tags for version 1.2.3 will be 1.2.3, 1.2-latest, 1-latest and latest the docker tags for version 2.3.4-beta.6 will be 2.3.4-beta.6, 2.3-beta, 2-beta and beta

Development

Docker Registry

To be able to push to the local registry with auth credentials, ssl certificates are required. This project uses self signed certs. To regenerate the certs run the following:

$ openssl req -new -newkey rsa:2048 -days 365 -nodes -x509 -keyout server.key -out server.crt

NOTE: When prompted for an FQDN it must be registry:5000 NOTE: The credentials for the local registry are user: iamweasel, pass: secretsquirrel