docs/qapidoc: create qmp-example directive

This is a directive that creates a syntactic sugar for creating
"Example" boxes very similar to the ones already used in the bitmaps.rst
document, please see e.g.
https://www.qemu.org/docs/master/interop/bitmaps.html#creation-block-dirty-bitmap-add

In its simplest form, when a custom title is not needed or wanted, and
the example body is *solely* a QMP example:

```
.. qmp-example::

   {body}
```

is syntactic sugar for:

```
.. admonition:: Example:

   .. code-block:: QMP

      {body}
```

When a custom, plaintext title that describes the example is desired,
this form:

```
.. qmp-example::
   :title: Defrobnification

   {body}
```

Is syntactic sugar for:

```
.. admonition:: Example: Defrobnification

   .. code-block:: QMP

      {body}
```

Lastly, when Examples are multi-step processes that require non-QMP
exposition, have lengthy titles, or otherwise involve prose with rST
markup (lists, cross-references, etc), the most complex form:

```
.. qmp-example::
   :annotated:

   This example shows how to use `foo-command`::

     {body}

   For more information, please see `frobnozz`.
```

Is desugared to:

```
.. admonition:: Example:

   This example shows how to use `foo-command`::

     {body}

   For more information, please see `frobnozz`.
```

Note that :annotated: and :title: options can be combined together, if
desired.

The primary benefit here being documentation source consistently using
the same directive for all forms of examples to ensure consistent visual
styling, and ensuring all relevant prose is visually grouped alongside
the code literal block.

Note that as of this commit, the code-block rST syntax "::" does not
apply QMP highlighting; you would need to use ".. code-block:: QMP". The
very next commit changes this behavior to assume all "::" code blocks
within this directive are QMP blocks.

Signed-off-by: John Snow <jsnow@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240717021312.606116-4-jsnow@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This commit is contained in:
John Snow 2024-07-16 22:13:05 -04:00 committed by Markus Armbruster
parent a7d07ccd20
commit 547864f9d4
1 changed files with 55 additions and 0 deletions

View File

@ -27,6 +27,7 @@ https://www.sphinx-doc.org/en/master/development/index.html
import os
import re
import textwrap
from typing import List
from docutils import nodes
from docutils.parsers.rst import Directive, directives
@ -35,6 +36,7 @@ from qapi.error import QAPIError, QAPISemError
from qapi.gen import QAPISchemaVisitor
from qapi.schema import QAPISchema
from sphinx.directives.code import CodeBlock
from sphinx.errors import ExtensionError
from sphinx.util.docutils import switch_source_input
from sphinx.util.nodes import nested_parse_with_titles
@ -538,10 +540,63 @@ class QAPIDocDirective(NestedDirective):
raise ExtensionError(str(err)) from err
class QMPExample(CodeBlock, NestedDirective):
"""
Custom admonition for QMP code examples.
When the :annotated: option is present, the body of this directive
is parsed as normal rST instead. Code blocks must be explicitly
written by the user, but this allows for intermingling explanatory
paragraphs with arbitrary rST syntax and code blocks for more
involved examples.
When :annotated: is absent, the directive body is treated as a
simple standalone QMP code block literal.
"""
required_argument = 0
optional_arguments = 0
has_content = True
option_spec = {
"annotated": directives.flag,
"title": directives.unchanged,
}
def admonition_wrap(self, *content) -> List[nodes.Node]:
title = "Example:"
if "title" in self.options:
title = f"{title} {self.options['title']}"
admon = nodes.admonition(
"",
nodes.title("", title),
*content,
classes=["admonition", "admonition-example"],
)
return [admon]
def run_annotated(self) -> List[nodes.Node]:
content_node: nodes.Element = nodes.section()
self.do_parse(self.content, content_node)
return content_node.children
def run(self) -> List[nodes.Node]:
annotated = "annotated" in self.options
if annotated:
content_nodes = self.run_annotated()
else:
self.arguments = ["QMP"]
content_nodes = super().run()
return self.admonition_wrap(*content_nodes)
def setup(app):
"""Register qapi-doc directive with Sphinx"""
app.add_config_value("qapidoc_srctree", None, "env")
app.add_directive("qapi-doc", QAPIDocDirective)
app.add_directive("qmp-example", QMPExample)
return {
"version": __version__,