Move documentation files to their place in the hierarchy; update SUMMARY.md github/anoa/doc_hierarchy anoa/doc_hierarchy

1 files changed, 177 insertions, 0 deletions

diff --git a/docs/development/code_style.md b/docs/development/code_style.md
new file mode 100644
index 0000000000..4d8e7c973d
--- /dev/null
+++ b/docs/development/code_style.md
@@ -0,0 +1,177 @@
+# Code Style
+
+## Formatting tools
+
+The Synapse codebase uses a number of code formatting tools in order to
+quickly and automatically check for formatting (and sometimes logical)
+errors in code.
+
+The necessary tools are detailed below.
+
+First install them with:
+
+```sh
+pip install -e ".[lint,mypy]"
+```
+
+-   **black**
+
+    The Synapse codebase uses [black](https://pypi.org/project/black/)
+    as an opinionated code formatter, ensuring all comitted code is
+    properly formatted.
+
+    Have `black` auto-format your code (it shouldn't change any
+    functionality) with:
+
+    ```sh
+    black . --exclude="\.tox|build|env"
+    ```
+
+-   **flake8**
+
+    `flake8` is a code checking tool. We require code to pass `flake8`
+    before being merged into the codebase.
+
+    Check all application and test code with:
+
+    ```sh
+    flake8 synapse tests
+    ```
+
+-   **isort**
+
+    `isort` ensures imports are nicely formatted, and can suggest and
+    auto-fix issues such as double-importing.
+
+    Auto-fix imports with:
+
+    ```sh
+    isort -rc synapse tests
+    ```
+
+    `-rc` means to recursively search the given directories.
+
+It's worth noting that modern IDEs and text editors can run these tools
+automatically on save. It may be worth looking into whether this
+functionality is supported in your editor for a more convenient
+development workflow. It is not, however, recommended to run `flake8` on
+save as it takes a while and is very resource intensive.
+
+## General rules
+
+-   **Naming**:
+    -   Use camel case for class and type names
+    -   Use underscores for functions and variables.
+-   **Docstrings**: should follow the [google code
+    style](https://google.github.io/styleguide/pyguide.html#38-comments-and-docstrings).
+    See the
+    [examples](http://sphinxcontrib-napoleon.readthedocs.io/en/latest/example_google.html)
+    in the sphinx documentation.
+-   **Imports**:
+    -   Imports should be sorted by `isort` as described above.
+    -   Prefer to import classes and functions rather than packages or
+        modules.
+
+        Example:
+
+        ```python
+        from synapse.types import UserID
+        ...
+        user_id = UserID(local, server)
+        ```
+
+        is preferred over:
+
+        ```python
+        from synapse import types
+        ...
+        user_id = types.UserID(local, server)
+        ```
+
+        (or any other variant).
+
+        This goes against the advice in the Google style guide, but it
+        means that errors in the name are caught early (at import time).
+
+    -   Avoid wildcard imports (`from synapse.types import *`) and
+        relative imports (`from .types import UserID`).
+
+## Configuration file format
+
+The [sample configuration file](./sample_config.yaml) acts as a
+reference to Synapse's configuration options for server administrators.
+Remember that many readers will be unfamiliar with YAML and server
+administration in general, so that it is important that the file be as
+easy to understand as possible, which includes following a consistent
+format.
+
+Some guidelines follow:
+
+-   Sections should be separated with a heading consisting of a single
+    line prefixed and suffixed with `##`. There should be **two** blank
+    lines before the section header, and **one** after.
+-   Each option should be listed in the file with the following format:
+    -   A comment describing the setting. Each line of this comment
+        should be prefixed with a hash (`#`) and a space.
+
+        The comment should describe the default behaviour (ie, what
+        happens if the setting is omitted), as well as what the effect
+        will be if the setting is changed.
+
+        Often, the comment end with something like "uncomment the
+        following to <do action>".
+
+    -   A line consisting of only `#`.
+    -   A commented-out example setting, prefixed with only `#`.
+
+        For boolean (on/off) options, convention is that this example
+        should be the *opposite* to the default (so the comment will end
+        with "Uncomment the following to enable [or disable]
+        <feature>." For other options, the example should give some
+        non-default value which is likely to be useful to the reader.
+
+-   There should be a blank line between each option.
+-   Where several settings are grouped into a single dict, *avoid* the
+    convention where the whole block is commented out, resulting in
+    comment lines starting `# #`, as this is hard to read and confusing
+    to edit. Instead, leave the top-level config option uncommented, and
+    follow the conventions above for sub-options. Ensure that your code
+    correctly handles the top-level option being set to `None` (as it
+    will be if no sub-options are enabled).
+-   Lines should be wrapped at 80 characters.
+-   Use two-space indents.
+-   `true` and `false` are spelt thus (as opposed to `True`, etc.)
+-   Use single quotes (`'`) rather than double-quotes (`"`) or backticks
+    (`` ` ``) to refer to configuration options.
+
+Example:
+
+```yaml
+## Frobnication ##
+
+# The frobnicator will ensure that all requests are fully frobnicated.
+# To enable it, uncomment the following.
+#
+#frobnicator_enabled: true
+
+# By default, the frobnicator will frobnicate with the default frobber.
+# The following will make it use an alternative frobber.
+#
+#frobincator_frobber: special_frobber
+
+# Settings for the frobber
+#
+frobber:
+  # frobbing speed. Defaults to 1.
+  #
+  #speed: 10
+
+  # frobbing distance. Defaults to 1000.
+  #
+  #distance: 100
+```
+
+Note that the sample configuration is generated from the synapse code
+and is maintained by a script, `scripts-dev/generate_sample_config`.
+Making sure that the output from this script matches the desired format
+is left as an exercise for the reader!