[![Join Slack room](https://img.shields.io/badge/%23task-chat%20room-blue.svg)](https://gophers.slack.com/messages/task) [![Build Status](https://travis-ci.org/go-task/task.svg?branch=master)](https://travis-ci.org/go-task/task) # Task - A task runner / simpler Make alternative written in Go Task is a simple tool that allows you to easily run development and build tasks. Task is written in Golang, but can be used to develop any language. It aims to be simpler and easier to use then [GNU Make][make]. - [Installation](#installation) - [Usage](#usage) - [Environment](#environment) - [OS specific task](#os-specific-task) - [Task directory](#task-directory) - [Task dependencies](#task-dependencies) - [Calling another task](#calling-another-task) - [Prevent unnecessary work](#prevent-unnecessary-work) - [Variables](#variables) - [Dynamic variables](#dynamic-variables) - [Go's template engine](#gos-template-engine) - [Help](#help) - [Silent mode](#silent-mode) - [Watch tasks](#watch-tasks-experimental) - [Task in the wild](#task-in-the-wild) - [Alternative task runners](#alternative-task-runners) ## Installation If you have a [Golang][golang] environment setup, you can simply run: ```bash go get -u -v github.com/go-task/task/cmd/task ``` Or you can download the binary from the [releases][releases] page and add to your `PATH`. DEB and RPM packages are also available. The `task_checksums.txt` file contains the SHA-256 checksum for each file. ## Usage Create a file called `Taskfile.yml` in the root of the project. The `cmds` attribute should contains the commands of a task. The example below allows compile a Go app and uses [Minify][minify] to concat and minify multiple CSS files into a single one. ```yml build: cmds: - go build -v -i main.go assets: cmds: - minify -o public/style.css src/css ``` Running the tasks is as simple as running: ```bash task assets build ``` Task uses [github.com/mvdan/sh](https://github.com/mvdan/sh), a native Go sh interpreter. So you can write sh/bash commands and it will work even on Windows, where `sh` or `bash` is usually not available. Just remember any executable called must be available by the OS or in PATH. If you ommit a task name, "default" will be assumed. ### Environment You can specify environment variables that are added when running a command: ```yml build: cmds: - echo $hallo env: hallo: welt ``` ### OS specific task If you add a `Taskfile_{{GOOS}}.yml` you can override or amend your taskfile based on the operating system. Example: Taskfile.yml: ```yml build: cmds: - echo "default" ``` Taskfile_linux.yml: ```yml build: cmds: - echo "linux" ``` Will print out `linux` and not default. It's also possible to have OS specific `Taskvars.yml` file, like `Taskvars_windows.yml`, `Taskfile_linux.yml` or `Taskvars_darwin.yml`. See the [variables section](#variables) below. ### Task directory By default, tasks will be executed in the directory where the Taskfile is located. But you can easily make the task run in another folder informing `dir`: ```yml serve: dir: public/www cmds: # run http server - caddy ``` ### Task dependencies You may have tasks that depends on others. Just pointing them on `deps` will make them run automatically before running the parent task: ```yml build: deps: [assets] cmds: - go build -v -i main.go assets: cmds: - minify -o public/style.css src/css ``` In the above example, `assets` will always run right before `build` if you run `task build`. A task can have only dependencies and no commands to group tasks together: ```yml assets: deps: [js, css] js: cmds: - minify -o public/script.js src/js css: cmds: - minify -o public/style.css src/css ``` If there are more than one dependency, they always run in parallel for better performance. ### Calling another task When a task has many dependencies, they are executed concurrently. This will often result in a faster build pipeline. But in some situations you may need to call other tasks serially. In this case, just use the following syntax: ```yml main-task: cmds: - task: task-to-be-called - task: another-task - echo "Both done" task-to-be-called: cmds: - echo "Task to be called" another-task: cmds: - echo "Another task" ``` Overriding variables in the called task is as simple as informing `vars` attribute: ```yml main-task: cmds: - task: write-file vars: {FILE: "hello.txt", CONTENT: "Hello!"} - task: write-file vars: {FILE: "world.txt", CONTENT: "World!"} write-file: cmds: - echo "{{.CONTENT}}" > {{.FILE}} ``` The above syntax is also supported in `deps`. > NOTE: It's also possible to call a task without any param prefixing it with `^`, but this syntax is deprecated: ```yml a-task: cmds: - ^another-task another-task: cmds: - echo "Another task" ``` ### Prevent unnecessary work If a task generates something, you can inform Task the source and generated files, so Task will prevent to run them if not necessary. ```yml build: deps: [js, css] cmds: - go build -v -i main.go js: cmds: - minify -o public/script.js src/js sources: - src/js/**/*.js generates: - public/script.js css: cmds: - minify -o public/style.css src/css sources: - src/css/**/*.css generates: - public/style.css ``` `sources` and `generates` can be files or file patterns. When both are given, Task will compare the modification date/time of the files to determine if it's necessary to run the task. If not, it will just print a message like `Task "js" is up to date`. If you prefer this check to be made by the content of the files, instead of its timestamp, just set the `method` property to `checksum`. You will probably want to ignore the `.task` folder in your `.gitignore` file (It's there that Task stores the last checksum). This feature is still experimental and can change until it's stable. ```yml build: cmds: - go build . sources: - ./*.go generates: - app{{exeExt}} method: checksum ``` > TIP: method `none` skips any validation and always run the task. Alternatively, you can inform a sequence of tests as `status`. If no error is returned (exit status 0), the task is considered up-to-date: ```yml generate-files: cmds: - mkdir directory - touch directory/file1.txt - touch directory/file2.txt # test existence of files status: - test -d directory - test -f directory/file1.txt - test -f directory/file2.txt ``` You can use `--force` or `-f` if you want to force a task to run even when up-to-date. ### Variables When doing interpolation of variables, Task will look for the below. They are listed below in order of importance (e.g. most important first): - Variables given while calling a task from another. (See [Calling another task](#calling-another-task) above) - Environment variables - Variables declared locally in the task - Variables available in the `Taskvars.yml` file Example of overriding with environment variables: ```bash $ TASK_VARIABLE=a-value task do-something ``` Since some shells don't support above syntax to set environment variables (Windows) tasks also accepts a similar style when not in the beginning of the command. Variables given in this form are only visible to the task called right before. ```bash $ task write-file FILE=file.txt "CONTENT=Hello, World!" print "MESSAGE=All done!" ``` Example of locally declared vars: ```yml print-var: cmds: echo "{{.VAR}}" vars: VAR: Hello! ``` Example of `Taskvars.yml` file: ```yml PROJECT_NAME: My Project DEV_MODE: production GIT_COMMIT: {sh: git log -n 1 --format=%h} ``` #### Dynamic variables The below syntax (`sh:` prop in a variable) is considered a dynamic variable. The value will be treated as a command and the output assigned. If there is one or more trailing newlines, the last newline will be trimmed. ```yml build: cmds: - go build -ldflags="-X main.Version={{.GIT_COMMIT}}" main.go vars: GIT_COMMIT: sh: git log -n 1 --format=%h ``` This works for all types of variables. > It's also possible to prefix the variable with `$` to have a dynamic variable, but this is now considered deprecated: ```yml # Taskvars.yml # recommended GIT_COMMIT: sh: git log -n 1 --format=%h # deprecated GIT_COMMIT: $git log -n 1 --format=%h ``` ### Go's template engine Task parse commands as [Go's template engine][gotemplate] before executing them. Variables are accessible through dot syntax (`.VARNAME`). All functions by the Go's [sprig lib](http://masterminds.github.io/sprig/) are available. The following example gets the current date in a given format: ```yml print-date: cmds: - echo {{now | date "2006-01-02"}} ``` Task also adds the following functions: - `OS`: Returns operating system. Possible values are "windows", "linux", "darwin" (macOS) and "freebsd". - `ARCH`: return the architecture Task was compiled to: "386", "amd64", "arm" or "s390x". - `splitLines`: Splits Unix (\n) and Windows (\r\n) styled newlines. - `catLines`: Replaces Unix (\n) and Windows (\r\n) styled newlines with a space. - `toSlash`: Does nothing on Unix, but on Windows converts a string from `\` path format to `/`. - `fromSlash`: Oposite of `toSlash`. Does nothing on Unix, but on Windows converts a string from `\` path format to `/`. - `exeExt`: Returns the right executable extension for the current OS (`".exe"` for Windows, `""` for others). Example: ```yml print-os: cmds: - echo '{{OS}} {{ARCH}}' - echo '{{if eq OS "windows"}}windows-command{{else}}unix-command{{end}}' # This will be path/to/file on Unix but path\to\file on Windows - echo '{{fromSlash "path/to/file"}}' enumerated-file: vars: CONTENT: | foo bar cmds: - | cat << EOF > output.txt {{range $i, $line := .CONTENT | splitLines -}} {{printf "%3d" $i}}: {{$line}} {{end}}EOF ``` > NOTE: There are some deprecated function names still available: `ToSlash`, `FromSlash` and `ExeExt`. These where changed for consistency with sprig lib. ### Help Running `task --list` (or `task -l`) lists all tasks with a description. The following taskfile: ```yml build: desc: Build the go binary. cmds: - go build -v -i main.go test: desc: Run all the go tests. cmds: - go test -race ./... js: cmds: - minify -o public/script.js src/js css: cmds: - minify -o public/style.css src/css ``` would print the following output: ```bash * build: Build the go binary. * test: Run all the go tests. ``` ## Silent mode Silent mode disables echoing of commands before Task runs it. For the following Taskfile: ```yml echo: cmds: - echo "Print something" ``` Normally this will be print: ```sh echo "Print something" Print something ``` With silent mode on, the below will be print instead: ```sh Print something ``` There's three ways to enable silent mode: * At command level: ```yml echo: cmds: - cmd: echo "Print something" silent: true ``` * At task level: ```yml echo: cmds: - echo "Print something" silent: true ``` * Or globally with `--silent` or `-s` flag If you want to suppress stdout instead, just redirect a command to `/dev/null`: ```yml echo: cmds: - echo "This will print nothing" > /dev/null ``` ## Watch tasks (experimental) If you give a `--watch` or `-w` argument, task will watch for files changes and run the task again. This requires the `sources` attribute to be given, so task know which files to watch. ## Task in the wild - [How I Build My Static Assets for Hugo][post-hugo] ## Alternative task runners - YAML based: - [tj/robo][robo] - [dogtools/dog][dog] - [goeuro/myke][myke] - [dreadl0ck/zeus][zeus] - Go based: - [go-godo/godo][godo] - [markbates/grift][grift] - [nstratos/make.go][make.go] - Make based: - [tj/mmake][mmake] [make]: https://www.gnu.org/software/make/ [releases]: https://github.com/go-task/task/releases [golang]: https://golang.org/ [gotemplate]: https://golang.org/pkg/text/template/ [robo]: https://github.com/tj/robo [dog]: https://github.com/dogtools/dog [myke]: https://github.com/goeuro/myke [zeus]: https://github.com/dreadl0ck/zeus [godo]: https://github.com/go-godo/godo [grift]: https://github.com/markbates/grift [make.go]: https://github.com/nstratos/make.go [mmake]: https://github.com/tj/mmake [sh]: https://github.com/mvdan/sh [post-hugo]: https://blog.carlmjohnson.net/post/2017/hugo-asset-pipeline/ [minify]: https://github.com/tdewolff/minify/tree/master/cmd/minify