grml - A simple build automation tool written in Go

TODO: Update the README. The syntax has changed with the latest release.

grml is a simple Makefile alternative. Build targets are defined in a grml.yaml file located in the project's root directory. This file uses the YAML syntax.

A minimal grml.yaml file can be expressed as follows:

targets:
    app:
        help:    build the app
        default: true
        run: |
            gb build all

The build is triggered with:

$ grml app

or just with the default target:

$ grml

The run section is called in a shell (sh) process. All sh expressions (if, elif, ...) are valid.

Outputs

For each target multiple outputs can be defined. Targets are skipped if the output files exist.

targets:
    resources:
        help: build the resources
        output:
            - build/resources
        run: |
            mkdir -p build
            touch build/resources

Dependencies

Dependencies can be specified within the deps section.

targets:
    app:
        help:    build the app
        deps:
            - resources
        run: |
            gb build all
    resources:
        help: build the resources
        output:
            - build/resources
        run: |
            mkdir -p build
            touch build/resources

Variables

Environment variables can be defined in the env section. These variables are passed to all run target processes.

env:
    version: 1.0.0

targets:
    app:
        help:    build the app
        default: true
        run: |
            echo "$version"

Variables are accessible with the ${} selector in the env, deps and output section.

env:
    version:    1.0.0
    buildDir:   build/
    destBin:    app-${version}

targets:
    app:
        help: build the app
        deps:
            - resources
        run: |
            echo "building app ${destBin}"
            gb build all

    resources:
        help: build the resources
        output:
            - ${buildDir}/resources
        run: |
            mkdir -p ${buildDir}
            touch ${buildDir}/resources

Additonal Variables

The process environment is inherited and following additonal variables are set:

KEY	VALUE
ROOT	Path to the root build directory containing the grml.yaml file

Final Example

env:
    version:    1.0.0
    buildDir:   build/
    destBin:    app-${version}

targets:
    app:
        help:    build the app
        default: true
        deps:
            - resources
            - db
        run: |
            echo "building app ${destBin}"
            gb build all

    resources:
        help:        build the resources
        help-group:  Resources
        deps:
            - images
        output:
            - ${buildDir}/resources
        run: |
            mkdir -p ${buildDir}
            touch ${buildDir}/resources

    images:
        help:        build the image resources
        help-group:  Resources
        output:
            - ${buildDir}/images
        run: |
            mkdir -p ${buildDir}
            touch ${buildDir}/images

    db:
        help: build the database files
        output:
            - ${buildDir}/db
        run: |
            mkdir -p ${buildDir}
            touch ${buildDir}/db