add contributing.md & update readme (#3643)

* add contributing.md & update readme

* add for developers section of docs to contributing.md

* remove relative wiki links

* readme spelling fix

* clarify discourse/docs idea for user 'recipes' to get featured

* remove coveralls from testing section

* fix api links & clarify docstring standard

* Contributing -> Contribute

* remove manual pip module installation instructions

* add link to testing wiki page on "how to contribute"

* add databse access examples

* added voting clarification

* Rename contributing.md to CONTRIBUTING.md

* remove out of date info

Includes references to gitter, the old 'good first issue' label and also
some updates to testing.

* No need for backticks around beets

We usually just typeset it as an ordinary noun, not as code. :)

* Whitespace

* End-to-end CONTRIBUTING pass

Co-authored-by: Adrian Sampson <adrian@radbox.org>

CONTRIBUTING.md

@@ -0,0 +1,165 @@
+# Thank you!
+
+First off, thank you for considering contributing to beets! It's people like you that make beets continue to succeed.
+
+These guidelines describe how you can help most effectively. By following these guidelines, you can make life easier for the development team. By following them, you indicate your respect for the maintainers' time; in return, the maintainers can reciprocate by helping to address your issue, review changes, and finalize pull requests.
+
+# Types of Contributions
+
+We love to get contributions from our community—you! There are many ways to contribute, whether you're a programmer or not.
+
+## Non-Programming
+
+* Promote beets! Help get the word out by telling your friends, writing a blog
+  post, or discussing it on a forum you frequent.
+* Improve the [documentation][docs]. It's incredibly easy to contribute here:
+  just find a page you want to modify and hit the "Edit on GitHub" button in
+  the upper-right. You can automatically send us a pull request for your
+  changes.
+* GUI design. For the time being, beets is a command-line-only affair. But
+  that's mostly because we don't have any great ideas for what a good GUI
+  should look like. If you have those great ideas, please get in touch.
+* Benchmarks. We'd like to have a consistent way of measuring speed
+  improvements in beets' tagger and other functionality as well as a way of
+  comparing beets' performance to other tools. You can help by compiling a
+  library of freely-licensed music files (preferably with incorrect metadata)
+  for testing and measurement.
+* Think you have a nice config or cool use-case for beets? We'd love to hear about it! Submit a post to our [our forums][forum] under the "Show and Tell" category for a chance to get featured in [the docs][advanced].
+* Consider helping out in [our forums][forum] by responding to support requests or driving some new discussions.
+
+[docs]: http://beets.readthedocs.org/
+[forum]: https://discourse.beets.io/
+[advanced]: https://beets.readthedocs.io/en/stable/guides/advanced.html
+
+## Programming
+
+* As a programmer (even if you're just a beginner!), you have a ton of opportunities to get your feet wet with beets.
+* For developing plugins, or hacking away at beets, there's some good information in the ["For Developers" section of the docs][dev-docs].
+
+[dev-docs]: https://beets.readthedocs.io/en/stable/dev/
+
+### Getting the Source
+
+The easiest way to get started with the latest beets source is to use [pip][] to install an "editable" package. This can be done with one command:
+
+    $ pip install -e git+https://github.com/beetbox/beets.git#egg=beets
+
+Or, equivalently:
+
+    $ git clone https://github.com/beetbox/beets.git
+    $ cd beets
+    $ pip install -e .
+
+If you already have a released version of beets installed, you may need to
+remove it first by typing `pip uninstall beets`. The pip command above will put
+the beets source in a `src/beets` directory and install the `beet` CLI script to
+a standard location on your system. You may want to use the `--src` option to specify
+the parent directory where the source will be checked out and the `--user` option
+such that the package will be installed to your home directory (compare with the output of
+`pip install --help`).
+
+[pip]: https://pip.pypa.io/
+
+### Code Contribution Ideas
+
+* We maintain a set of [issues marked as "bite-sized"](https://github.com/beetbox/beets/labels/bitesize). These are issues that would serve as a good introduction to the codebase. Claim one and start exploring!
+* Like testing? Our [test coverage](https://codecov.io/github/beetbox/beets) is somewhat low. You can help out by finding low-coverage modules or checking out other [testing-related issues](https://github.com/beetbox/beets/labels/testing).
+* There are several ways to improve the tests in general (see [Testing](https://github.com/beetbox/beets/wiki/Testing)) and some places to think about performance optimization (see [Optimization](https://github.com/beetbox/beets/wiki/Optimization)).
+* Not all of our code is up to our coding conventions. In particular, the [API documentation](https://beets.readthedocs.io/en/stable/dev/api.html) are currently quite sparse. You can help by adding to the docstrings in the code and to the documentation pages themselves. beets follows [PEP-257](https://www.python.org/dev/peps/pep-0257/) for docstrings and in some places, we also sometimes use [ReST autodoc syntax for Sphinx](https://www.sphinx-doc.org/en/master/usage/extensions/autodoc.html) to, for example, refer to a class name.
+
+## Your First Contribution
+
+If this is your first time contributing to an open source project, welcome! If you are confused at all about how to contribute or what to contribute, take a look at [this great tutorial](http://makeapullrequest.com/), or stop by our [forums](https://discourse.beets.io/) if you have any questions.
+
+We maintain a list of issues we reserved for those new to open source labeled ["first timers only"](https://github.com/beetbox/beets/issues?q=is%3Aopen+is%3Aissue+label%3A%22first+timers+only%22). Since the goal of these issues is to get users comfortable with contributing to an open source project, please do not hesitate to ask any questions.
+
+## How to Submit Your Work
+
+Do you have a great bug fix, new feature, or documentation expansion you'd like to contribute? Follow these steps to create a GitHub pull request and your code will ship in no time.
+
+1. Fork the beets repository and clone it (see above) to create a workspace.
+2. Make your changes.
+3. Add tests. If you've fixed a bug, write a test to ensure that you've actually fixed it. If there's a new feature or plugin, please contribute tests that show that your code does what it says.
+4. Add documentation. If you've added a new command flag, for example, find the appropriate page under `docs/` where it needs to be listed.
+5. Add a changelog entry to `docs/changelog.rst` near the top of the document.
+6. Run the tests and style checker. The easiest way to run the tests is to use [tox](https://tox.readthedocs.org/en/latest/). For more information on running tests, see our [Testing wiki page](https://github.com/beetbox/beets/wiki/Testing).
+7. Push to your fork and open a pull request! We'll be in touch shortly.
+8. If you add commits to a pull request, please add a comment or re-request a review after you push them since GitHub doesn't automatically notify us when commits are added.
+
+Remember, code contributions have four parts: the code, the tests, the documentation, and the changelog entry. Thank you for contributing!
+
+
+# The Code
+
+The documentation has an [API section](https://beets.readthedocs.io/en/stable/dev/api.html) that serves as an introduction to beets' design.
+
+## Coding Conventions
+
+There are a few coding conventions we use in beets:
+
+* Whenever you access the library database, do so through the provided Library
+  methods or via a Transaction object. Never call `lib.conn.*` directly.
+  For example, do this:
+  ```
+  with g.lib.transaction() as tx:
+        rows = tx.query('SELECT DISTINCT "{0}" FROM "{1}" ORDER BY "{2}"'
+                        .format(field, model._table, sort_field))
+  ```
+  To fetch Item objects from the database, use lib.items(...) and supply a query as an argument. Resist the urge to write raw SQL for your query. If you must use lower-level    queries into the database, do this:
+  ```
+  with lib.transaction() as tx:
+      rows = tx.query('SELECT …')
+  ```
+  Transaction objects help control concurrent access to the database and assist in debugging conflicting accesses.
+* Always use the [future imports][] `print_function`, `division`, and
+  `absolute_import`, but *not* `unicode_literals`. These help keep your code
+  modern and will help in the eventual move to Python 3.
+* `str.format()` should be used instead of the `%` operator
+* Never `print` informational messages; use the [logging][] module instead. In
+  particular, we have our own logging shim, so you'll see `from beets import
+  logging` in most files.
+    * Always log Unicode strings (e.g., `log.debug(u"hello world")`).
+    * The loggers use [str.format][]-style logging instead of ``%``-style, so
+      you can type `log.debug(u"{0}", obj)` to do your formatting.
+* Exception handlers must use `except A as B:` instead of `except A, B:`.
+
+[future imports]: http://docs.python.org/library/__future__.html
+[logging]: http://docs.python.org/library/logging.html
+[str.format]: http://docs.python.org/library/stdtypes.html#str.format
+[modformat]: http://docs.python.org/library/stdtypes.html#string-formatting-operations
+
+We follow [PEP 8](http://www.python.org/dev/peps/pep-0008/) for style. You can use `tox -e lint` to check your code for any style errors.
+
+## Handling Paths
+
+A great deal of convention deals with the handling of **paths**. Paths are
+stored internally—in the database, for instance—as byte strings (i.e., `bytes` instead of `str` in Python 3). This is because POSIX operating systems' path names are only
+reliably usable as byte strings—operating systems typically recommend but do not require that filenames use a given encoding, so violations of any reported encoding are inevitable.
+On Windows, the strings are always encoded with UTF-8; on
+Unix, the encoding is controlled by the filesystem. Here are some guidelines to
+follow:
+
+* If you have a Unicode path or you're not sure whether something is Unicode or
+  not, pass it through `bytestring_path` function in the `beets.util` module to
+  convert it to bytes.
+* Pass every path name trough the `syspath` function (also in `beets.util`)
+  before sending it to any *operating system* file operation (`open`, for
+  example). This is necessary to use long filenames (which, maddeningly, must
+  be Unicode) on Windows. This allows us to consistently store bytes in the
+  database but use the native encoding rule on both POSIX and Windows.
+* Similarly, the `displayable_path` utility function converts bytestring paths
+  to a Unicode string for displaying to the user. Every time you want to print
+  out a string to the terminal or log it with the `logging` module, feed it
+  through this function.
+
+## Editor Settings
+
+Personally, I work on beets with [vim](http://www.vim.org/). Here are some
+`.vimrc` lines that might help with PEP 8-compliant Python coding:
+
+    filetype indent on
+    autocmd FileType python setlocal shiftwidth=4 tabstop=4 softtabstop=4 expandtab shiftround autoindent
+
+Consider installing [this alternative Python indentation
+plugin](https://github.com/mitsuhiko/vim-python-combined). I also like
+[neomake](https://github.com/neomake/neomake) with its flake8 checker.

README.rst

@@ -90,11 +90,9 @@ Check out the `Getting Started`_ guide for more information.
 Contribute
 ----------
 
-Check out the `Hacking`_ page on the wiki for tips on how to help out.
+Thank you for considering contributing to ``beets``! Whether you're a programmer or not, you should be able to find all the info you need at `Contributing.md`_.
-You might also be interested in the `For Developers`_ section in the docs.
 
-.. _Hacking: https://github.com/beetbox/beets/wiki/Hacking
+.. _Contributing.md: https://github.com/beetbox/beets/blob/contributing.md/contributing.md
-.. _For Developers: https://beets.readthedocs.io/en/stable/dev/
 
 Read More
 ---------
@@ -105,6 +103,15 @@ news and updates.
 .. _its Web site: https://beets.io/
 .. _@b33ts: https://twitter.com/b33ts/
 
+Contact
+-------
+* Encountered a bug you'd like to report or have an idea for a new feature? Check out our `issue tracker`_! If your issue or feature hasn't already been reported, please `open a new ticket`_ and we'll be in touch with you shortly. If you'd like to vote on a feature/bug, simply give a :+1: on issues you'd like to see prioritized over others.
+* Need help/support, would like to start a discussion, or would just like to introduce yourself to the team? Check out our `forums`_!
+
+.. _issue tracker: https://github.com/beetbox/beets/issues
+.. _open a new ticket: https://github.com/beetbox/beets/issues/new/choose
+.. _forums: https://discourse.beets.io/
+
 Authors
 -------