python-brewer 0.3.0
A Homebrew formula template generator for Python packages
License: MIT

python-brewer
=============

Overview
--------

``python-brewer`` is a command-line utility (written in Python) to help
with generating formula templates for `Homebrew <http://brew.sh>`__ from
installed Python packages. The aim is not to generate perfect,
ready-to-go Homebrew formulae out of the box: the aim is to generate a
**template** for you, taking some of the harder slog work out of the
process.

Primarily, it takes an installed package, finds all of its installed
dependencies, and generates a template containing ``resource``
references to all of these dependencies (as per the installed versions).
It also automatically computes the SHA256 hashes of all of the packages
by downloading their source distributions from PyPI.

See Homebrew's `Python for Formula
Authors <https://github.com/Homebrew/brew/blob/master/docs/Python-for-Formula-Authors.md>`__
guide for more details on submitting Python-based formulae for Homebrew.

Requirements
------------

In order to install ``python-brewer``, you will need:

-  Python 2.7+ or Python 3.5+
-  ``pip``

Installation
------------

Installing via PyPI (install into a virtual environment please):

.. code:: bash

    > pip install python-brewer

Basic Usage
-----------

As a simple example, we'll generate a base template for
`Statik <https://getstatik.com>`__ - the static web site generator. The
first step is to install the package into your virtual environment:

.. code:: bash

    > pip install -U statik

The next step is to use the ``pybrew`` command, provided by
``python-brewer``, to generate the Homebrew formula template. In this
case, at the time of this writing, I was generating the formula for
``v0.14.2`` of **Statik**.

.. code:: bash

    > pybrew \
        # The name of the formula
        -n "Statik" \
        # A description for the formula
        -d "Python-based, generic static web site generator aimed at developers" \
        # Project homepage
        -H https://getstatik.com \
        # HEAD of Git repo
        -g https://github.com/thanethomson/statik.git \
        # Latest release of the package
        -r https://github.com/thanethomson/statik/archive/v0.14.2.tar.gz \
        # Name of the Python package
        statik \
        # Output file to which to write the template
        statik.rb

At the time of this writing, the following file was generated by
``pybrew``:

.. code:: ruby

    class Statik < Formula
      include Language::Python::Virtualenv

      desc "Python-based, generic static web site generator aimed at developers"
      homepage "https://getstatik.com"
      url "https://github.com/thanethomson/statik/archive/v0.14.2.tar.gz"
      sha256 "ef2e67ecf8a1a59b71b5c88b86c7335e32cc480d3156716c3b2e7691edab7620"
      head "https://github.com/thanethomson/statik.git"

      # TODO: If you're submitting an existing package, make sure you include your
      #       bottle block here.

      depends_on :python if MacOS.version <= :snow_leopard

      resource "future" do
        url "https://pypi.python.org/packages/00/2b/8d082ddfed935f3608cc61140df6dcbf0edea1bc3ab52fb6c29ae3e81e85/future-0.16.0.tar.gz"
        sha256 "e39ced1ab767b5936646cedba8bcce582398233d6a627067d4c6a454c90cfedb"
      end

      resource "tornado" do
        url "https://pypi.python.org/packages/1e/7c/ea047f7bbd1ff22a7f69fe55e7561040e3e54d6f31da6267ef9748321f98/tornado-4.4.2.tar.gz"
        sha256 "2898f992f898cd41eeb8d53b6df75495f2f423b6672890aadaf196ea1448edcc"
      end

      resource "argh" do
        url "https://pypi.python.org/packages/e3/75/1183b5d1663a66aebb2c184e0398724b624cecd4f4b679cb6e25de97ed15/argh-0.26.2.tar.gz"
        sha256 "e9535b8c84dc9571a48999094fda7f33e63c3f1b74f3e5f3ac0105a58405bb65"
      end

      resource "pathtools" do
        url "https://pypi.python.org/packages/e7/7f/470d6fcdf23f9f3518f6b0b76be9df16dcc8630ad409947f8be2eb0ed13a/pathtools-0.1.2.tar.gz"
        sha256 "7c35c5421a39bb82e58018febd90e3b6e5db34c5443aaaf742b3f33d4655f1c0"
      end

      resource "PyYAML" do
        url "https://pypi.python.org/packages/4a/85/db5a2df477072b2902b0eb892feb37d88ac635d36245a72a6a69b23b383a/PyYAML-3.12.tar.gz"
        sha256 "592766c6303207a20efc445587778322d7f73b161bd994f227adaa341ba212ab"
      end

      resource "watchdog" do
        url "https://pypi.python.org/packages/54/7d/c7c0ad1e32b9f132075967fc353a244eb2b375a3d2f5b0ce612fd96e107e/watchdog-0.8.3.tar.gz"
        sha256 "7e65882adb7746039b6f3876ee174952f8eaaa34491ba34333ddf1fe35de4162"
      end

      resource "httpwatcher" do
        url "https://pypi.python.org/packages/02/97/055185c6a54e470ef943556b613bc56975e82da3f456bdd08f036cf7cae8/httpwatcher-0.4.0.tar.gz"
        sha256 "2f84c93a3766a11a69f2d339f143889558bd5eccee77574593c39111a3202645"
      end

      resource "MarkupSafe" do
        url "https://pypi.python.org/packages/c0/41/bae1254e0396c0cc8cf1751cb7d9afc90a602353695af5952530482c963f/MarkupSafe-0.23.tar.gz"
        sha256 "a4ec1aff59b95a14b45eb2e23761a0179e98319da5a7eb76b56ea8cdc7b871c3"
      end

      resource "jinja2" do
        url "https://pypi.python.org/packages/f4/3f/28387a5bbc6883082c16784c6135440b94f9d5938fb156ff579798e18eda/Jinja2-2.9.4.tar.gz"
        sha256 "aab8d8ca9f45624f1e77f2844bf3c144d180e97da8824c2a6d7552ad039b5442"
      end

      resource "lipsum" do
        url "https://pypi.python.org/packages/59/97/00636d64bc77dc173d782995de1b56dde39c70bb97112964452709b4d9aa/lipsum-0.1.2.tar.gz"
        sha256 "ba5f46cef19104c07f889b14486a3772845fc25afa1eb5e2eee1f2d9badcb8ab"
      end

      resource "markdown" do
        url "https://pypi.python.org/packages/d4/32/642bd580c577af37b00a1eb59b0eaa996f2d11dfe394f3dd0c7a8a2de81a/Markdown-2.6.7.tar.gz"
        sha256 "daebf24846efa7ff269cfde8c41a48bb2303920c7b2c7c5e04fa82e6282d05c0"
      end

      resource "Unidecode" do
        url "https://pypi.python.org/packages/ba/64/410af95d27f2a8824112d17ed41ea7ce6d2cbc8a4832c2e548d3408fad0a/Unidecode-0.04.20.tar.gz"
        sha256 "ed4418b4b1b190487753f1cca6299e8076079258647284414e6d607d1f8a00e0"
      end

      resource "python-slugify" do
        url "https://pypi.python.org/packages/63/86/ecf7b570089d794a9476c7411a06a329eb8e386f3407576640ccbe7a4698/python-slugify-1.2.1.tar.gz"
        sha256 "501182ec738cc8b743ae5c76c183f4427187ef016257f062b3fa594f60916e34"
      end

      resource "six" do
        url "https://pypi.python.org/packages/b3/b2/238e2590826bfdd113244a40d9d3eb26918bd798fc187e2360a8367068db/six-1.10.0.tar.gz"
        sha256 "105f8d68616f8248e24bf0e9372ef04d3cc10104f1980f54d57b2ce73a5ad56a"
      end

      resource "SQLAlchemy" do
        url "https://pypi.python.org/packages/da/04/8048a5075d6e29235bbd6f1ea092a38dbe2630c670e73d4aa923a4e5521c/SQLAlchemy-1.1.5.tar.gz"
        sha256 "68fb40049690e567ebda7b270176f5abf0d53d9fbd515fec4e43326f601119b6"
      end

      def install
        virtualenv_install_with_resources
      end

      # TODO: Add your package's tests here
    end

Of course, I've since added the original ``bottle`` block for the script
and the package's unit tests. See `this
commit <https://github.com/thanethomson/homebrew-core/commit/b30f8a8f1aa55e15200e9862d90818ff4b8c1947>`__
and
`statik.rb <https://github.com/Homebrew/homebrew-core/blob/master/Formula/statik.rb>`__
in ``homebrew-core`` for more details.

Python 2 or 3?
--------------

While ``python-brewer`` runs well on Python 2.7+ and Python 3.5+, it's
important to note that sometimes your dependencies will be different
based on which Python version you're running, and based on the nature of
your dependencies. Sometimes, certain packages include different
dependencies when running Python 3, e.g.
`Tornado <https://github.com/tornadoweb/tornado/blob/master/setup.py>`__.

As such, ``python-brewer`` automatically changes the Python dependency
based on the detected Python version. In the above package for
**Statik**, I ran ``pybrew`` with Python 2 and, as such, automatically
added the line:

.. code:: ruby

      depends_on :python if MacOS.version <= :snow_leopard

If I had run it with Python 3, it would have added the following line
instead:

.. code:: ruby

      depends_on :python3

This will, of course, cause Homebrew to attempt to install its own
Python 3 distribution for your package.

Contributing
------------

Please feel free to contribute! If you want to add or fix something in
``python-brewer``, please:

1. Fork the project
2. Make your changes in a feature branch
3. Submit a pull request

License
-------

**The MIT License (MIT)**

Copyright (c) 2017 Thane Thomson

Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.