git.taskfile.build/usage.md

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Usage

Running the task file requires a shell alias: alias task='./task'
Show the available commands with task help.
From the specification the project can be installed with task install.
Execute all commands with task all.

Image

See taskfile.build/image for details.

Naming

The naming of functions is important. There are basically two styles:

1. Action + Object
2. Object + Action

The task file functions use the first style. The name of the function starts with an action followed by an object. The object name can be singular or plural.

Examples for actions: activate, install, dev, develop, init, build, start, update, remove, delete, enable, disable, template, convert, create, edit, change, get, set, patch, fetch, generate, push, pull, import, export, list, publish, release, test, setup, prepare, restart, stop, store, restore, translate, upgrade, zip, visualize, sync, switch, run, reset, load, dump, checkout, commit, drop, deploy, handle, trigger, render, lint, uninstall, split, parse, fix, refactor, transform, cat, ls, rm, serve, help, show, filter, login, logout, encrypt, decrypt, upload, download, analyse, transpile, compile, minify, copy

Examples for objects: env, venv, submodule, container, database, snippet, model, module, repo, mail, doc, dependency, view, user, vault, file, host, node, log, password, hash, script, requirement, part, component, system, workspace, image, process, state, platform, dir, folder, readme, overview, lang, level, request, response, result, worker, server, proxy, workflow, volume, network, package, field, value, secret, chart, node, edge, function, method, firewall, html, css, image, svg, style, query, native, group, notebook

Objects can be tools: odoo, vupress, nodejs, zsh, bash, fish, podman, kind, minikube, helm, nvim, docker, podman, rust, python, tmux, vim, helix, system, git, pass, llm, sql, dotenv, javascript, vue, vite, astro, typescript, turbo, pnpm, eslint, jenkins, k8s, nextcloud, postgres, metabase, ansible, prometheus, grafana, hugo, deno, bun, babel, panda, gulp, grunt, electron, react, express, mongodb, angular, ionic, meteor, webpack, bower, jupyter

Generate Function Names

Style

The bash scripts follow the Bash Style Guide | ysap.sh. Have a look at the AGENTS.md for details on the applied styling.

Patterns

The task file showed above is very basic. Commands can have parameters and call each other. The following is a collection of more complex task file patterns.

Set default parameter

Fallback to a default value for a parameter.

build() {
    local platform="amd64"
    if [[ -n "$1" ]]; then
        platform="$1"
    fi

Ensure parameter is not empty

Check the first param and exit if it is empty.

deploy() {
    if [[ -z "$1" ]]; then echo "\$1 is empty."; exit; fi

Prompt for input

Use read to ask for inputs.

if [[ -z "$2" ]]; then
	read -p "Enter the task description: " task_description
else
	task_description="$2"
fi

Setup local env vars

Define env vars at the beginning of the task file.

CONFIGURATION_FILE="file.conf"
GIT_BRANCH=$(git symbolic-ref --short -q HEAD)

Template with env vars

Create a parameterized file from a template. Requires envsubst.

template-with-env() {
    echo "Template $CONFIGURATION_FILE"

    export CONFIGURATION_1
    export CONFIGURATION_2=${CONFIGURATION_2:="value"}

    envsubst < "file.conf.template" > "$CONFIGURATION_FILE"
}

Create Python virtual env

Initialize Python virtual env with uv.

init-venv() {
    if [[ ! -d "venv$GIT_BRANCH" ]]; then
        echo "Init venv$GIT_BRANCH with $(uv --version)."
        uv venv "venv$GIT_BRANCH"
    fi
}

Activate Python virtual env

activate-venv() {
    echo "Source virtualenv venv$GIT_BRANCH."
    source "venv$GIT_BRANCH/bin/activate"
    echo "$(python --version) is active."
}

Call a Python script

Run a Python script.

generate-password-hash() {
    activate-venv
    if [[ -z "$1" ]]; then echo "\$1 is empty."; exit; fi
    export PASSWORD_PLAIN="$1"
    bin/password-hash
}

The Python script: bin/password-hash

#!/usr/bin/env python3

import os
from passlib.context import CryptContext
crypt_context = CryptContext(schemes=['pbkdf2_sha512', 'plaintext'], deprecated=['plaintext'])

password = os.environ.get('PASSWORD_PLAIN')
print(crypt_context.hash(password))

Command with named parameters

Assuming you have a docker-compose.yml and would like to start selected or all containers.

start() {
    if [[ "$1" =~ "db" ]]; then
        docker compose up -d db
    fi

    if [[ "$1" =~ "admin" ]]; then
        docker compose up -d admin
        echo "Open http://localhost:8000 url in your browser."
    fi

    if [[ "$1" =~ "odoo" ]]; then
        docker compose up -d odoo
        echo "Open http://localhost:8069 url in your browser."
    fi

    if [[ "$1" =~ "mail" ]]; then
	    docker compose up -d mail
        echo "Open http://localhost:8025 url in your browser."
    fi
}

Start all containers with task start and selected with task start db,admin.

Run commands in container

Use docker exec -i to run commands in a container.

drop-db() {
    local database="$1"
    if [[ -z "$database" ]]; then
        database="example"
    fi

    docker exec -i db psql "postgres://odoo:odoo@localhost:5432/postgres" -c "SELECT pg_terminate_backend(pid) FROM pg_stat_activity WHERE datname = '$database';"
    docker exec -i db psql "postgres://odoo:odoo@localhost:5432/postgres" -c "DROP DATABASE \"$database\";"
}

Loop over files and folders

Use for to loop over file, folders or arrays.

render() {
    echo "Update index.html for all folders"
    for folder in ./*; do
        if [[ -f "$folder/README.md" ]]; then
            cd "$folder" || exit
            md2html README.md _site/index.html
            cd .. || exit
        fi
    done
}

Parse and convert a file

With this function you can split a file into multiple parts whenever a specific keyword is matching. In this example the keyword is !vault.

convert-vault-file() {
    local file_path="$1"
    local temp_file=$(mktemp)
    local temp_part_file=$(mktemp)
    local write_finished=false
    local current_key=""

    while IFS= read -r line; do
        # Check for keyword
        if [[ "$line" =~ "!vault" ]]; then
            # Process previous vault entry if it exists
            if [[ "$write_finished" = true ]] && [[ -n "$current_key" ]] && [[ -s "$temp_part_file" ]]; then
                # Decrypt part file and write to assemble file
                ansible-vault decrypt "$temp_part_file"
                local value=$(cat "$temp_part_file")
                echo "$current_key: $value" >> "$temp_file"
            fi

            # Set up for new vault entry
            current_key=$(echo "$line" | cut -d':' -f1)
            # Clear the file
            : > "$temp_part_file"
            # Flag as ready to write
            write_finished=true
        else
            if [[ "$write_finished" = true ]]; then
                # Pipe into part file
                echo "$line" >> "$temp_part_file"
            fi
        done
    done < "$file_path"

    # Process the final vault entry
    if [[ "$write_finished" = true ]] && [[ -n "$current_key" ]] && [[ -s "$temp_part_file" ]]; then
        ansible-vault decrypt "$temp_part_file"
        local value=$(cat "$temp_part_file")
        echo "$current_key: $value" >> "$temp_file"
    fi

    # Output assembled file
    cat "$temp_file"
    # Cleanup temp files
    rm -f "$temp_file"
    rm -f "$temp_part_file"
}

Process data

This pattern tries to match the worklow of a jupyter notebook. Create a folder with the data processing scripts:

scripts
├── 01_import-mail-data
├── 02_transform-mail-data
└── 03_export-mail-data

The following function lists the scripts and asks for the number of scripts to run. Every script until the entered number is concatenated and executed.

process-data() {
    while true; do
        local scripts=($(ls scripts))

        echo -e "Available scripts:\n"
        for index in "${!scripts[@]}"; do
            echo "$((index+1)): ${scripts[$index]}"
        done
        echo ""
        read -p "Enter the number of scripts to run (or 'q' to quit): " user_input
        if [[ "$user_input" = "q" ]]; then
            break
        fi

        local temp_file=$(mktemp)
        for index in "${!scripts[@]}"; do
            if (( $user_input >= $((index+1)) )); then
                cat "scripts/${scripts[$index]}" >> "$temp_file"
                echo >> "$temp_file"
            fi
        done

        clear
        echo -e "\nPython Output:\n\n---"
        python "$temp_file"
        local exit_code=$?
        echo -e "---\n"
        echo -e "Exit code: $exit_code\n"
        rm "$temp_file"
    done
}

Integration

The task file is intended to be integrated into the shell setup. Where applications provides a domain specific language (DSL) ensure that the DSL only calls the task file.

Completion

With the output of task help the task commands can be completed.

Completion for bash: /etc/bash_completion.d/task_completions

#!/usr/bin/env bash

_task_completions() {
    local cur prev commands
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"

    commands=$(./task help | grep -A999 -e '---' | awk '{print $2}' | sed 's/^[[:space:]]*//' | grep -v '^$' | tr '\n' ' ')

    if [[ ${COMP_CWORD} == 1 ]]; then
        COMPREPLY=( $(compgen -W "${commands}" -- "${cur}") )
    elif [[ ${COMP_CWORD} == 2 ]]; then
        COMPREPLY=( $(compgen -f -- "${cur}") )
    else
        COMPREPLY=()
    fi
}

complete -F _task_completions task
complete -F _task_completions t

Completion for zsh: ~/.oh-my-zsh/completions/_task

#compdef task t

_arguments '1: :->tasks' '*: :_files'

case "$state" in
    tasks)
        args=$(./task help | grep -A999 -e '---' | awk '{print $2}' | sed 's/^[[:space:]]*//' | grep -v '^$' | tr '\n' ' ')
        args="$args help"
        _arguments "1:profiles:($args)"
        ;;
esac

The completion also works for task alias alias t='./task'.

GitHub Actions

Running task file commands in GitHub Actions is highly recommended. This way you can run the same CI/CD procedures in the GitHub runner as you do on your localhost.

The GitHub Actions config is simple: .github/workflows/test.yml

on:
    pull_request:
        branches:
            - 'main'
    push:
        branches:
            - 'main'

jobs:
    task-all:
        runs-on: ubuntu-latest
        steps:
            - uses: actions/checkout@v4
            - uses: actions/setup-python@v5
              with:
                  python-version: '3.12'
            - name: Install uv
              uses: astral-sh/setup-uv@v5
            - name: Install
              run: ./task install
            - name: Lint
              run: ./task lint

Jenkins

Run task file commands in Jenkins: Jenkinsfile

pipeline {

    agent any

    stages {
        stage('version') {
            steps {
                script {
                    currentBuild.description = sh (script: 'git log -1 --pretty=%B', returnStdout: true).trim()
                }
                sh './task version'
            }
        }
        stage('install') {
            steps {
                sh './task install'
            }
        }
        stage('lint') {
            steps {
                sh './task lint'
            }
        }
    }
}%