poethepoet 0.9.0

A task runner that works well with poetry.

A task runner that works well with poetry.

Features

✅ Straight forward declaration of project tasks in your pyproject.toml (kind of like npm scripts)

✅ Task are run in poetry’s virtualenv by default

✅ Tasks can be commands (with or without a shell) or references to python functions (like tool.poetry.scripts)

✅ Short and sweet commands with extra arguments passed to the task poe [options] task [task_args]

✅ Tasks can specify and reference environment variables as if they were evaluated by a shell

✅ Tasks are self documenting, with optional help messages (just run poe without arguments)

✅ Tasks can be defined as a sequence of other tasks

✅ Shell completion of task names (and global options too for zsh)

Installation

Into your project (so it works inside poetry shell):

poetry add --dev poethepoet

And into your default python environment (so it works outside of poetry shell)

pip install poethepoet

Enable tab completion for your shell

Poe comes with tab completion scripts for bash, zsh, and fish to save you keystrokes. How to install them will depend on your shell setup.

Zsh

# oh-my-zsh
mkdir -p ~/.oh-my-zsh/completions
poe _zsh_completion > ~/.oh-my-zsh/completions/_poe

# without oh-my-zsh
mkdir -p ~/.zfunc/
poe _zsh_completion > ~/.zfunc/_poetry

Note that you’ll need to start a new shell for the new completion script to be loaded. If it still doesn’t work try adding a call to compinit to the end of your zshrc file.

Bash

# System bash
poe _bash_completion > /etc/bash_completion.d/poe.bash-completion

# Homebrew bash
poe _bash_completion > $(brew --prefix)/etc/bash_completion.d/poe.bash-completion

How to ensure installed bash completions are enabled may vary depending on your system.

Fish

# Fish
poe _fish_completion > ~/.config/fish/completions/poe.fish

# Homebrew fish
poe _fish_completion > (brew --prefix)/share/fish/vendor_completions.d/poe.fish

Basic Usage

Define tasks in your pyproject.toml

See a real example

[tool.poe.tasks]
test       = "pytest --cov=poethepoet"                                # simple command based task
mksandwich = { script = "my_package.sandwich:build" }                 # python script based task
tunnel     = { shell = "ssh -N -L 0.0.0.0:8080:$PROD:8080 $PROD &" }  # shell script based task

Run tasks with the poe cli

poe test

Additional arguments are passed to the task so

poe test -v tests/favorite_test.py

results in the following being run inside poetry’s virtualenv

pytest --cov=poethepoet -v tests/favorite_test.py

You can also run it like so if you fancy

python -m poethepoet [options] task [task_args]

Or install it as a dev dependency with poetry and run it like

poetry add --dev poethepoet
poetry run poe [options] task [task_args]

Though it that case you might like to do alias poe='poetry run poe'.

Types of task

There are four types of task: simple commands (cmd), python scripts (script), shell scripts (shell), and composite tasks (sequence).

• Command tasks contain a single command that will be executed without a shell. This covers most basic use cases for example:

  [tool.poe.tasks]
  format = "black ."  # strings are interpreted as commands by default
  clean = """
  # Multiline commands including comments work too. Unescaped whitespace is ignored.
  rm -rf .coverage
         .mypy_cache
         .pytest_cache
         dist
         ./**/__pycache__
  """
  lint = { "cmd": "pylint poethepoet" }  # Inline tables with a cmd key work too
  greet = "echo Hello $USER"  # Environment variables work, even though there's no shell!

• Script tasks contain a reference to a python callable to import and execute, for example:

  [tool.poe.tasks]
  fetch-assets = { "script" = "my_package.assets:fetch" }
  fetch-images = { "script" = "my_package.assets:fetch(only='images')" }

  As in the second example, is it possible to hard code literal arguments to the target callable.

  If extra arguments are passed to task on the command line, then they will be available to the called python function via sys.argv.

• Shell tasks are similar to simple command tasks except that they are executed inside a new shell, and can consist of multiple separate commands, command substitution, pipes, background processes, etc.

  An example use case for this might be opening some ssh tunnels in the background with one task and closing them with another like so:

  [tool.poe.tasks]
  pfwd = { "shell" = "ssh -N -L 0.0.0.0:8080:$STAGING:8080 $STAGING & ssh -N -L 0.0.0.0:5432:$STAGINGDB:5432 $STAGINGDB &" }
  pfwdstop = { "shell" = "kill $(pgrep -f "ssh -N -L .*:(8080|5432)")" }

• Composite tasks are defined as a sequence of other tasks as an array.

  By default the contents of the array are interpreted as references to other tasks (actually a ref task type), though this behaviour can be altered by setting the global default_array_item_task_type option to the name of another task type such as _cmd_, or by setting the default_item_type option locally on the sequence task.

  An example task with references

  [tool.poe.tasks]
  
  test = "pytest --cov=src"
  build = "poetry build"
  _publish = "poetry publish"
  release = ["test", "build", "_publish"]

  Note that tasks with names prefixed with _ are not included in the documentation or directly executable, but can be useful for cases where a task is only needed for a sequence.

  An example task with inline tasks expressed via inline tables

  release = [
    { cmd = "pytest --cov=src" },
    { script = "devtasks:build" },
    { ref = "_publish" },
  ]

  An example task with inline script subtasks using default_item_type

  release.sequence = [
    "devtasks:run_tests(all=True)",
    "devtasks:build",
    "devtasks:publish",
  ]
  release.default_item_type = "script"

  A failure (non-zero result) will result in the rest of the tasks in the sequence not being executed, unless the ignore_fail option is set on the task like so:

  [tool.poe.tasks]
  attempts.sequence = ["task1", "task2", "task3"]
  attempts.ignore_fail = true

Task level configuration

Task help text

You can specifiy help text to be shown alongside the task name in the list of available tasks (such as when executing poe with no arguments), by adding a help key like so:

[tool.poe.tasks]
style = {cmd = "black . --check --diff", help = "Check code style"}

Environment variables

You can specify arbitrary environment variables to be set for a task by providing the env key like so:

[tool.poe.tasks]
serve.script = "myapp:run"
serve.env = { PORT = 9001 }

Notice this example uses deep keys which can be more convenient but aren’t as well supported by some toml implementations.

Project-wide configuration options

Global environment variables

You can configure environment variables to be set for all poe tasks in the pyproject.toml file by specifying tool.poe.env like so

[tool.poe.env]
VAR1 = "FOO"
VAR2 = "BAR"

Run poe from anywhere

By default poe will detect when you’re inside a project with a pyproject.toml in the root. However if you want to run it from elsewhere that is supported too by using the –root option to specify an alternate location for the toml file. The task will run with the given location as the current working directory.

In all cases the path to project root (where the pyproject.toml resides) will be available as $POE_ROOT within the command line and process.

Change the default task type

By default tasks defined as strings are interpreted as shell commands, and script tasks require the more verbose table syntax to specify. For example:

my_cmd_task = "cmd args"
my_script_task = { "script" = "my_package.my_module:run" }

This behaviour can be reversed by setting the default_task_type option in your pyproject.toml like so:

[tool.poe]
default_task_type = "script"

[tool.poe.tasks]
my_cmd_task = { "cmd" = "cmd args" }
my_script_task = "my_package.my_module:run"

Contributing

There’s plenty to do, come say hi in the issues! 👋

TODO

☐ support declaring specific arguments for a task

☐ support conditional execution (a bit like make targets)

☐ support verbose mode for documentation that shows task definitions

☐ support different task executors such as specifying a non-poetry venv, or working with pipenv,

☐ support third party task or executor types as plugins

☐ maybe provide poe as a poetry plugin

☐ maybe support plumbum based tasks

Licence

MIT.