Authors Guide – Contributing to Plone Training

Authors Guide#

This guide is for authors of Training documentation. It covers configuring quality checks and syntax for writing markup that is of particular interest to authors. For general markup syntax, see General Guide to Writing Documentation.

HTML and Open Graph Metadata#

All documents must have a myst topmatter key with an html_meta directive at the top of every page. When rendered to HTML, it inserts <meta> tags for improved search engine results and nicer social media posts. Authors should include at least description, property=og:description, property=og:title, and keywords meta tags.

The following is an example of html_meta. Note that the content of the two tags description and property=og:description should be identical.

---
myst:
  html_meta:
    "description": "Authors' guide to writing Plone Trainings. It covers configuring quality checks and syntax for writing markup that is of particular interest to authors."
    "property=og:description": "Authors' guide to writing Plone Trainings. It covers configuring quality checks and syntax for writing markup that is of particular interest to authors."
    "property=og:title": "Authors Guide"
    "keywords": "Plone, Trainings, SEO, meta, presentation, exercises, solutions, Vale, linkcheck, lexer"
---

This renders in the HTML <head> section as follows.

<meta content="Authors' guide to writing Plone Trainings. It covers configuring quality checks and syntax for writing markup that is of particular interest to authors." name="description" />
<meta content="Authors' guide to writing Plone Trainings. It covers configuring quality checks and syntax for writing markup that is of particular interest to authors." property="og:description" />
<meta content="Authors Guide" property="og:title" />
<meta content="Plone, Trainings, SEO, meta, presentation, exercises, solutions, Vale, linkcheck, lexer" name="keywords" />

Additional Open Graph metadata is implemented through the Sphinx extension sphinxext-opengraph and the MyST html_meta directive, which resolves to the Docutils meta directive. See the site-wide configuration in conf.py.

Writing Presentation Markup#

The presentation build creates an abbreviated version of the documentation. It is designed for projectors which are typically low resolution and have limited screen space. Authors should use bullet points instead of long narrative text.

The command make presentation as described in presentation is implemented through the Sphinx only directive.

The presentation builder is configured in Makefile using the sphinx-build flag -t.

To show something in the presentation build and hide in the html build, use the following syntax.

```{only} presentation
> This will appear only in the presentation build.
```

This will render as follows.

To hide something in the presentation build and show in the html build, use the following syntax.

```{only} not presentation
> I am hiding from the presentation build.
```

This will render as follows.

I am hiding from the presentation build.

Writing Exercises and Solutions#

We use Sphinx Design's dropdowns to hide and show solutions to exercises in the trainings.

We use its options of :animate: fade-in-slide-down and :icon: question to animate and provide an icon for the item.

Note that the markup uses MyST nested directives.

````{dropdown} This is a title
:animate: fade-in-slide-down
:icon: question

```{code-block} python
:linenos:
:emphasize-lines: 1, 3

a = 2
print("my 1st line")
print(f"my {a}nd line")
```

````

This will render as follows.

This is a title
1a = 2
2print("my 1st line")
3print(f"my {a}nd line")

Quality checks#

We strive for high quality documentation, setting the following minimum standards.

Markup syntax must be valid#

See both the specific markup syntax above and general markup in General Guide to Writing Documentation.

To validate markup, run the following command.

make html

Open /_build/html/index.html in a web browser.

American English spelling, grammar, and syntax, and style guide#

Spellings are enforced through Vale. Plone uses American English.

Spelling is configured in Makefile, .vale.ini, and in files in styles/Vocab/Plone/.

Authors should add new words and proper names using correct casing to styles/Vocab/Plone/accept.txt, sorted alphabetically and case-insensitive.

Vale also provides English grammar and syntax checking, as well as a Style Guide. We follow the Microsoft Writing Style Guide.

To perform all these checks, run the following command.

make vale

Because it is difficult to automate good American English grammar and syntax, we do not strictly enforce it. We also understand that contributors might not be fluent in English. We encourage contributors to make a reasonable effort, and to request a review of their pull request from community members who are fluent in English to fix grammar and syntax. Please ask!

Syntax highlighting#

Pygments provides syntax highlighting in Sphinx.

When including code snippets, you should specify the language. Authors must use a proper Pygments lexer and not generate warnings.

The snippet must be valid syntax for the language you specify, else it will not be highlighted properly. Avoid adding comments to code snippets, unless you use valid comment syntax for that language. For example, JSON does not allow comments.

Do not indicate elided or omitted code with ellipses (... or ). These are almost never valid syntax and will cause syntax highlighting to fail for the code block.

Choosing a Lexer#

Some lexers are less than perfect. If your code block does not highlight well, then consider specifying a less ambitious lexer, such as text.

Use shell for commands to be issued in a terminal session. Do not include shell prompts. This will make commands easy to copy and paste for readers.

Use console for output of a shell session. If you have a mix of a shell command and its output, then use console.

If xml does not work well, then try html.

jsx has a complex syntax that is difficult to parse. We have high hopes for the project jsx-lexer. We include it in our requirements.txt file. Please contribute to its further development.

The lexers html+ng2, scss, http, less are also suboptimal and particular.

If no other lexer works well, then fall back to text. At least then the build will succeed without warnings, although syntax highlighting for such snippets will not appear.

Validate the Lexer#

Always build the page to validate syntax. Your own training should not be merged into the larger Training docs if there are any Sphinx warnings. The Sphinx console will display any warnings, such as the following.

/Plone/training/voltohandson/introtoblocks.md:55: WARNING: Could not lex literal_block as "jsx". Highlighting skipped.

The above warning indicates that the syntax is not valid. Common mistakes include:

  • Using ... or to indicate omitted code. It is preferable to never use ellipses. If you must do that, comment it out using the language's comment syntax.

  • Using comments in JSON.

  • A previous code block bleeds through to the next due to invalid MyST syntax.

To validate code block syntax, run the following command.

make html

An online demo of all lexers that Pygments supports may be helpful to test out your code blocks and snippets for syntax highlighting. You can also use the pygmentize binary.

When using the online lexer, if any red-bordered rectangles appear, then the lexer for Pygments interprets your snippet as not valid. You can search the Pygments issue tracker for possible solutions, or submit a pull request to enhance the lexer.

Synchronize the Browser While Editing#

Use sphinx-autobuild to view changes in the browser while editing documentation.

make livehtml

You can open a browser at http://127.0.0.1:8000/ to preview the documentation.