Task uses [mvdan.cc/sh](https://mvdan.cc/sh/), a native Go sh interpreter. So you can write sh/bash commands, and it will work even on Windows, where `sh` or `bash` are usually not available. Just remember any executable called must be available by the OS or in PATH.
If you omit a task name, "default" will be assumed.
The intention of having the `.dist` variants is to allow projects to have one committed version (`.dist`) while still allowing individual users to override the Taskfile by adding an additional `Taskfile.yml` (which would be on `.gitignore`).
### 从子目录运行 Taskfile
If a Taskfile cannot be found in the current working directory, it will walk up the file tree until it finds one (similar to how `git` works). When running Task from a subdirectory like this, it will behave as if you ran it from the directory containing the Taskfile.
You can use this functionality along with the special `{{.USER_WORKING_DIR}}` variable to create some very useful reusable tasks. For example, if you have a monorepo with directories for each microservice, you can `cd` into a microservice directory and run a task command to bring it up without having to create multiple tasks or Taskfiles with identical content. For example:
```yaml
version: '3'
tasks:
up:
dir: '{{.USER_WORKING_DIR}}'
preconditions:
- test -f docker-compose.yml
cmds:
- docker-compose up -d
```
In this example, we can run `cd <service>` and `task up` and as long as the `<service>` directory contains a `docker-compose.yml`, the Docker composition will be brought up.
### 运行全局 Taskfile
If you call Task with the `--global` (alias `-g`) flag, it will look for your home directory instead of your working directory. In short, Task will look for a Taskfile on either `$HOME/Taskfile.yml` or `$HOME/Taskfile.yaml` paths.
This is useful to have automation that you can run from anywhere in your system!
When running your global Taskfile with `-g`, tasks will run on `$HOME` by default, and not on your working directory!
As mentioned in the previous section, the `{{.USER_WORKING_DIR}}` special variable can be very handy here to run stuff on the directory you're calling `task -g` from.
If you want to share tasks between different projects (Taskfiles), you can use the importing mechanism to include other Taskfiles using the `includes` keyword:
```yaml
version: '3'
includes:
docs: ./documentation # will look for ./documentation/Taskfile.yml
docker: ./DockerTasks.yml
```
The tasks described in the given Taskfiles will be available with the informed namespace. So, you'd call `task docs:serve` to run the `serve` task from `documentation/Taskfile.yml` or `task docker:build` to run the `build` task from the `DockerTasks.yml` file.
Relative paths are resolved relative to the directory containing the including Taskfile.
### 操作系统特定 Taskfile
With `version: '2'`, task automatically includes any `Taskfile_{{OS}}.yml` if it exists (for example: `Taskfile_windows.yml`, `Taskfile_linux.yml` or `Taskfile_darwin.yml`). Since this behavior was a bit too implicit, it was removed on version 3, but you still can have a similar behavior by explicitly importing these files:
```yaml
version: '3'
includes:
build: ./Taskfile_{{OS}}.yml
```
### 包含 Taskfile 的目录
By default, included Taskfile's tasks are run in the current directory, even if the Taskfile is in another directory, but you can force its tasks to run in another directory by using this alternative syntax:
Includes marked as internal will set all the tasks of the included file to be internal as well (see the [Internal tasks](#internal-tasks) section below). This is useful when including utility tasks that are not intended to be used directly by the user.
```yaml
version: '3'
includes:
tests:
taskfile: ./taskfiles/Utils.yml
internal: true
```
### 包含的 Taskfile 的变量
You can also specify variables when including a Taskfile. This may be useful for having reusable Taskfile that can be tweaked or even included more than once:
When including a Taskfile, you can give the namespace a list of `aliases`. This works in the same way as [task aliases](#task-aliases) and can be used together to create shorter and easier-to-type commands.
Vars declared in the included Taskfile have preference over the variables in the including Taskfile! If you want a variable in an included Taskfile to be overridable, use the [default function](https://go-task.github.io/slim-sprig/defaults.html): `MY_VAR: '{{.MY_VAR | default "my-default-value"}}'`.
Internal tasks are tasks that cannot be called directly by the user. They will not appear in the output when running `task --list|--list-all`. Other tasks may call internal tasks in the usual way. This is useful for creating reusable, function-like tasks that have no useful purpose on the command line.
```yaml
version: '3'
tasks:
build-image-1:
cmds:
- task: build-image
vars:
DOCKER_IMAGE: image-1
build-image:
internal: true
cmds:
- docker build -t {{.DOCKER_IMAGE}} .
```
## Task 目录
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`:
```yaml
version: '3'
tasks:
serve:
dir: public/www
cmds:
# run http server
- caddy
```
If the directory does not exist, `task` creates it.
## Task 依赖
> Dependencies run in parallel, so dependencies of a task should not depend one another. If you want to force tasks to run serially, take a look at the [Calling Another Task](#calling-another-task) section below.
You may have tasks that depend on others. Just pointing them on `deps` will make them run automatically before running the parent task:
If you want to restrict the running of tasks to explicit platforms, this can be achieved using the `platforms:` key. Tasks can be restricted to a specific OS, architecture or a combination of both. On a mismatch, the task or command will be skipped, and no error will be thrown.
The values allowed as OS or Arch are valid `GOOS` and `GOARCH` values, as defined by the Go language [here](https://github.com/golang/go/blob/master/src/go/build/syslist.go).
The `build-windows` task below will run only on Windows, and on any architecture:
```yaml
version: '3'
tasks:
build-windows:
platforms: [windows]
cmds:
- echo 'Running command on Windows'
```
This can be restricted to a specific architecture as follows:
```yaml
version: '3'
tasks:
build-windows-amd64:
platforms: [windows/amd64]
cmds:
- echo 'Running command on Windows (amd64)'
```
It is also possible to restrict the task to specific architectures:
```yaml
version: '3'
tasks:
build-amd64:
platforms: [amd64]
cmds:
- echo 'Running command on amd64'
```
Multiple platforms can be specified as follows:
```yaml
version: '3'
tasks:
build:
platforms: [windows/amd64, darwin]
cmds:
- echo 'Running command on Windows (amd64) and macOS'
```
Individual commands can also be restricted to specific platforms:
```yaml
version: '3'
tasks:
build:
cmds:
- cmd: echo 'Running command on Windows (amd64) and macOS'
When a task has many dependencies, they are executed concurrently. This will often result in a faster build pipeline. However, in some situations, you may need to call other tasks serially. In this case, use the following syntax:
```yaml
version: '3'
tasks:
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:
NOTE: If you want to call a task declared in the root Taskfile from within an [included Taskfile](#including-other-taskfiles), add a leading `:` like this: `task: :task-name`.
`sources` and `generates` can be files or file patterns. When given, Task will compare the checksum of the source 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 modification timestamp of the files, instead of its checksum (content), just set the `method` property to `timestamp`.
```yaml
version: '3'
tasks:
build:
cmds:
- go build .
sources:
- ./*.go
generates:
- app{{exeExt}}
method: timestamp
```
In situations where you need more flexibility the `status` keyword can be used. You can even combine the two. See the documentation for [status](#using-programmatic-checks-to-indicate-a-task-is-up-to-date) for an example.
By default, task stores checksums on a local `.task` directory in the project's directory. Most of the time, you'll want to have this directory on `.gitignore` (or equivalent) so it isn't committed. (If you have a task for code generation that is committed it may make sense to commit the checksum of that task as well, though).
If you want these files to be stored in another directory, you can set a `TASK_TEMP_DIR` environment variable in your machine. It can contain a relative path like `tmp/task` that will be interpreted as relative to the project directory, or an absolute or home path like `/tmp/.task` or `~/.task` (subdirectories will be created for each project).
Each task has only one checksum stored for its `sources`. If you want to distinguish a task by any of its input variables, you can add those variables as part of the task's label, and it will be considered a different task.
This is useful if you want to run a task once for each distinct set of inputs until the sources actually change. For example, if the sources depend on the value of a variable, or you if you want the task to rerun if some arguments change even if the source has not.
For the `checksum` (default) or `timestamp` method to work, it is only necessary to inform the source files. When the `timestamp` method is used, the last time of the running the task is considered as a generate.
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:
```yaml
version: '3'
tasks:
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
```
Normally, you would use `sources` in combination with `generates` - but for tasks that generate remote artifacts (Docker images, deploys, CD releases) the checksum source and timestamps require either access to the artifact or for an out-of-band refresh of the `.checksum` fingerprint file.
Two special variables `{{.CHECKSUM}}` and `{{.TIMESTAMP}}` are available for interpolation within `status` commands, depending on the method assigned to fingerprint the sources. Only `source` globs are fingerprinted.
Note that the `{{.TIMESTAMP}}` variable is a "live" Go `time.Time` struct, and can be formatted using any of the methods that `time.Time` responds to.
See [the Go Time documentation](https://golang.org/pkg/time/) for more information.
You can use `--force` or `-f` if you want to force a task to run even when up-to-date.
Also, `task --status [tasks]...` will exit with a non-zero exit code if any of the tasks are not up-to-date.
`status` can be combined with the [fingerprinting](#by-fingerprinting-locally-generated-files-and-their-sources) to have a task run if either the the source/generated artifacts changes, or the programmatic check fails:
```yaml
version: '3'
tasks:
build:prod:
desc: Build for production usage.
cmds:
- composer install
# Run this task if source files changes.
sources:
- composer.json
- composer.lock
generates:
- ./vendor/composer/installed.json
- ./vendor/autoload.php
# But also run the task if the last build was not a production build.
In addition to `status` checks, `preconditions` checks are the logical inverse of `status` checks. That is, if you need a certain set of conditions to be _true_ you can use the `preconditions` stanza. `preconditions` are similar to `status` lines, except they support `sh` expansion, and they SHOULD all return 0.
```yaml
version: '3'
tasks:
generate-files:
cmds:
- mkdir directory
- touch directory/file1.txt
- touch directory/file2.txt
# test existence of files
preconditions:
- test -f .env
- sh: "[ 1 = 0 ]"
msg: "One doesn't equal Zero, Halting"
```
Preconditions can set specific failure messages that can tell a user what steps to take using the `msg` field.
If a task has a dependency on a sub-task with a precondition, and that precondition is not met - the calling task will fail. Note that a task executed with a failing precondition will not run unless `--force` is given.
Unlike `status`, which will skip a task if it is up to date and continue executing tasks that depend on it, a `precondition` will fail a task, along with any other tasks that depend on it.
If a task executed by multiple `cmds` or multiple `deps` you can control when it is executed using `run`. `run` can also be set at the root of the Taskfile to change the behavior of all the tasks unless explicitly overridden.
Supported values for `run`:
*`always` (default) always attempt to invoke the task regardless of the number of previous executions
*`once` only invoke this task once regardless of the number of references
*`when_changed` only invokes the task once for each unique set of variables passed into the task
```yaml
version: '3'
tasks:
default:
cmds:
- task: generate-file
vars: { CONTENT: '1' }
- task: generate-file
vars: { CONTENT: '2' }
- task: generate-file
vars: { CONTENT: '2' }
generate-file:
run: when_changed
deps:
- install-deps
cmds:
- echo {{.CONTENT}}
install-deps:
run: once
cmds:
- sleep 5 # long operation like installing packages
```
## 变量
When doing interpolation of variables, Task will look for the below. They are listed below in order of importance (i.e. most important first):
- Variables declared in the task definition
- Variables given while calling a task from another (See [Calling another task](#calling-another-task) above)
- Variables of the [included Taskfile](#including-other-taskfiles) (when the task is included)
- Variables of the [inclusion of the Taskfile](#vars-of-included-taskfiles) (when the task is included)
- Global variables (those declared in the `vars:` option in the Taskfile)
- Environment variables
Example of sending parameters with environment variables:
Since some shells do not support the above syntax to set environment variables (Windows) tasks also accept a similar style when not at the beginning of the command.
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 are one or more trailing newlines, the last newline will be trimmed.
```yaml
version: '3'
tasks:
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.
## 将 CLI 参数转发到 cmds
If `--` is given in the CLI, all following parameters are added to a special `.CLI_ARGS` variable. This is useful to forward arguments to another command.
With the `defer` keyword, it's possible to schedule cleanup to be run once the task finishes. The difference with just putting it as the last command is that this command will run even when the task fails.
In the example below, `rm -rf tmpdir/` will run even if the third command fails:
```yaml
version: '3'
tasks:
default:
cmds:
- mkdir -p tmpdir/
- defer: rm -rf tmpdir/
- echo 'Do work on tmpdir/'
```
If you want to move the cleanup command into another task, that is possible as well:
Due to the nature of how the [Go's own `defer` work](https://go.dev/tour/flowcontrol/13), the deferred commands are executed in the reverse order if you schedule multiple of them.
Task parse commands as [Go's template engine](https://golang.org/pkg/text/template/) before executing them. Variables are accessible through dot syntax (`.VARNAME`).
All functions by the Go's [slim-sprig lib](https://go-task.github.io/slim-sprig/) are available. The following example gets the current date in a given format:
```yaml
version: '3'
tasks:
print-date:
cmds:
- echo {{now | date "2006-01-02"}}
```
Task also adds the following functions:
-`OS`: Returns the 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`: Opposite 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).
-`shellQuote`: Quotes a string to make it safe for use in shell scripts. Task uses [this Go function](https://pkg.go.dev/mvdan.cc/sh/v3@v3.4.0/syntax#Quote) for this. The Bash dialect is assumed.
-`splitArgs`: Splits a string as if it were a command's arguments. Task uses [this Go function](https://pkg.go.dev/mvdan.cc/sh/v3@v3.4.0/shell#Fields)
Example:
```yaml
version: '3'
tasks:
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
```
## 帮助
Running `task --list` (or `task -l`) lists all tasks with a description. The following Taskfile:
If you want to see all tasks, there's a `--list-all` (alias `-a`) flag as well.
## 显示任务摘要
Running `task --summary task-name` will show a summary of a task. The following Taskfile:
```yaml
version: '3'
tasks:
release:
deps: [build]
summary: |
Release your project to github
It will build your project before starting the release.
Please make sure that you have set GITHUB_TOKEN before starting.
cmds:
- your-release-tool
build:
cmds:
- your-build-tool
```
with running `task --summary release` would print the following output:
```
task: release
Release your project to github
It will build your project before starting the release.
Please make sure that you have set GITHUB_TOKEN before starting.
dependencies:
- build
commands:
- your-release-tool
```
If a summary is missing, the description will be printed. If the task does not have a summary or a description, a warning is printed.
Please note: *showing the summary will not execute the command*.
## Task 别名
Aliases are alternative names for tasks. They can be used to make it easier and quicker to run tasks with long or hard-to-type names. You can use them on the command line, when [calling sub-tasks](#calling-another-task) in your Taskfile and when [including tasks](#including-other-taskfiles) with aliases from another Taskfile. They can also be used together with [namespace aliases](#namespace-aliases).
```yaml
version: '3'
tasks:
generate:
aliases: [gen]
cmds:
- task: gen-mocks
generate-mocks:
aliases: [gen-mocks]
cmds:
- echo "generating..."
```
## 重写 Task 名称
Sometimes you may want to override the task name printed on the summary, up-to-date messages to STDOUT, etc. In this case, you can just set `label:`, which can also be interpolated with variables:
```yaml
version: '3'
tasks:
default:
- task: print
vars:
MESSAGE: hello
- task: print
vars:
MESSAGE: world
print:
label: 'print-{{.MESSAGE}}'
cmds:
- echo "{{.MESSAGE}}"
```
## 静默模式
Silent mode disables the echoing of commands before Task runs it. For the following Taskfile:
```yaml
version: '3'
tasks:
echo:
cmds:
- echo "Print something"
```
Normally this will be printed:
```sh
echo "Print something"
Print something
```
With silent mode on, the below will be printed instead:
```sh
Print something
```
There are four ways to enable silent mode:
* At command level:
```yaml
version: '3'
tasks:
echo:
cmds:
- cmd: echo "Print something"
silent: true
```
* At task level:
```yaml
version: '3'
tasks:
echo:
cmds:
- echo "Print something"
silent: true
```
* Globally at Taskfile level:
```yaml
version: '3'
silent: true
tasks:
echo:
cmds:
- echo "Print something"
```
* Or globally with `--silent` or `-s` flag
If you want to suppress STDOUT instead, just redirect a command to `/dev/null`:
Dry run mode (`--dry`) compiles and steps through each task, printing the commands that would be run without executing them. This is useful for debugging your Taskfiles.
## 忽略错误
You have the option to ignore errors during command execution. Given the following Taskfile:
```yaml
version: '3'
tasks:
echo:
cmds:
- exit 1
- echo "Hello World"
```
Task will abort the execution after running `exit 1` because the status code `1` stands for `EXIT_FAILURE`. However, it is possible to continue with execution using `ignore_error`:
```yaml
version: '3'
tasks:
echo:
cmds:
- cmd: exit 1
ignore_error: true
- echo "Hello World"
```
`ignore_error` can also be set for a task, which means errors will be suppressed for all commands. Nevertheless, keep in mind that this option will not propagate to other tasks called either by `deps` or `cmds`!
## 输出语法
By default, Task just redirects the STDOUT and STDERR of the running commands to the shell in real-time. This is good for having live feedback for logging printed by commands, but the output can become messy if you have multiple commands running simultaneously and printing lots of stuff.
To make this more customizable, there are currently three different output options you can choose:
-`interleaved` (default)
-`group`
-`prefixed`
To choose another one, just set it to root in the Taskfile:
```yaml
version: '3'
output: 'group'
tasks:
# ...
```
The `group` output will print the entire output of a command once after it finishes, so you will not have live feedback for commands that take a long time to run.
When using the `group` output, you can optionally provide a templated message to print at the start and end of the group. This can be useful for instructing CI systems to group all of the output for a given task, such as with [GitHub Actions' `::group::` command](https://docs.github.com/en/actions/learn-github-actions/workflow-commands-for-github-actions#grouping-log-lines) or [Azure Pipelines](https://docs.microsoft.com/en-us/azure/devops/pipelines/scripts/logging-commands?expand=1&view=azure-devops&tabs=bash#formatting-commands).
```yaml
version: '3'
output:
group:
begin: '::group::{{.TASK}}'
end: '::endgroup::'
tasks:
default:
cmds:
- echo 'Hello, World!'
silent: true
```
```bash
$ task default
::group::default
Hello, World!
::endgroup::
```
When using the `group` output, you may swallow the output of the executed command on standard output and standard error if it does not fail (zero exit code).
```yaml
version: '3'
silent: true
output:
group:
error_only: true
tasks:
passes: echo 'output-of-passes'
errors: echo 'output-of-errors' && exit 1
```
```bash
$ task passes
$ task errors
output-of-errors
task: Failed to run task "errors": exit status 1
```
The `prefix` output will prefix every line printed by a command with `[task-name]` as the prefix, but you can customize the prefix for a command with the `prefix:` attribute:
When running interactive CLI applications inside Task they can sometimes behave weirdly, especially when the [output mode](#output-syntax) is set to something other than `interleaved` (the default), or when interactive apps are run in parallel with other tasks.
The `interactive: true` tells Task this is an interactive application and Task will try to optimize for it:
```yaml
version: '3'
tasks:
default:
cmds:
- vim my-file.txt
interactive: true
```
If you still have problems running an interactive app through Task, please open an issue about it.
## 短 Task 语法
Starting on Task v3, you can now write tasks with a shorter syntax if they have the default settings (e.g. no custom `env:`, `vars:`, `desc:`, `silent:` , etc):
```yaml
version: '3'
tasks:
build: go build -v -o ./app{{exeExt}} .
run:
- task: build
- ./app{{exeExt}} -h localhost -p 8080
```
## `set` 和 `shopt`
It's possible to specify options to the [`set`](https://www.gnu.org/software/bash/manual/html_node/The-Set-Builtin.html) and [`shopt`](https://www.gnu.org/software/bash/manual/html_node/The-Shopt-Builtin.html) builtins. This can be added at global, task or command level.
```yaml
version: '3'
set: [pipefail]
shopt: [globstar]
tasks:
# `globstar` required for double star globs to work
With the flags `--watch` or `-w` task will watch for file changes and run the task again. This requires the `sources` attribute to be given, so task knows which files to watch.
The default watch interval is 5 seconds, but it's possible to change it by either setting `interval: '500ms'` in the root of the Taskfile passing it as an argument like `--interval=500ms`.
