[v2,06/10] Documentation: Install API documentation within HTML directory
diff mbox series

Message ID 20250911230115.25335-7-laurent.pinchart@ideasonboard.com
State New
Headers show
Series
  • Documentation theming update
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Commit Message

Laurent Pinchart Sept. 11, 2025, 11:01 p.m. UTC
The libcamera documentation is made of high-level documentation and
guides, written as ReStructuredText and compiled to HTML by Sphinx, and
API reference documentation, written as comments in the code and
compiled to HTML by Doxygen.

Due to meson limitations that make it difficult to place output files in
subdirectories, the compilation process produces an html/ directory for
the Sphinx documentation, and api-html/ and internal-api-html/
directories for the Doxygen documentation. When deploying the
documentation to the libcamera.org website, the api-html and
internal-api-html/ directories are moved within html/ to make the
documentation self-contained.

The Sphinx and Doxygen documentation link to each other. The links are
generated using relative paths, based on the directory hierarchy on the
website. This makes them broken when navigating the documentation in the
build tree or in the directory where libcamera is installed.

Fix this by standardizing on the directories hierarchy of the website in
the build and install directories:

- For the build directory, we can't easily build the Doxygen
  documentation in a subdirectory of the Sphinx documentation due to
  limitations of meson. Keep the existing output directories, and
  replace the html/api-html/ and html/internal-api-html/ placeholder
  directories with symlinks to the Doxygen output directories. This is
  handled by a small custom Sphinx extension.

- For the install directory, install the Doxygen documentation to
  html/api-html/ and html/internal-api-html/. This overwrites the
  placeholders.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
Changes since v1:

- Split from "[PATCH 4/6] documentation: Include API docs in the sphinx
  documentation"
- Avoid copying the doxygen documentation
- Use a sphinx extension to generate symlinks
---
 Documentation/conf.py.in                 | 26 +++++----
 Documentation/extensions/doxygen-link.py | 73 ++++++++++++++++++++++++
 Documentation/meson.build                | 19 ++++--
 3 files changed, 104 insertions(+), 14 deletions(-)
 create mode 100644 Documentation/extensions/doxygen-link.py

Patch
diff mbox series

diff --git a/Documentation/conf.py.in b/Documentation/conf.py.in
index 34fa3956f49e..5e0a7cff2984 100644
--- a/Documentation/conf.py.in
+++ b/Documentation/conf.py.in
@@ -9,14 +9,8 @@ 
 
 # -- Path setup --------------------------------------------------------------
 
-# If extensions (or modules to document with autodoc) are in another directory,
-# add these directories to sys.path here. If the directory is relative to the
-# documentation root, use os.path.abspath to make it absolute, like shown here.
-#
-# import os
-# import sys
-# sys.path.insert(0, os.path.abspath('.'))
-
+import sys
+sys.path.insert(0, "@CURRENT_SRCDIR@/extensions")
 
 # -- Project information -----------------------------------------------------
 
@@ -39,6 +33,7 @@  author = 'The libcamera documentation authors'
 extensions = [
     'sphinx.ext.graphviz',
     'sphinxcontrib.doxylink',
+    'doxygen-link',
 ]
 
 graphviz_output_format = 'svg'
@@ -75,14 +70,25 @@  pygments_style = None
 doxylink = {
     'doxy-pub': (
         '@TOP_BUILDDIR@/Documentation/api-html/tagfile.xml',
-        '../api-html/',
+        'api-html/',
     ),
     'doxy-int': (
         '@TOP_BUILDDIR@/Documentation/internal-api-html/tagfile.xml',
-        '../internal-api-html/',
+        'internal-api-html/',
     ),
 }
 
+doxygen_links = [
+    [
+        '@TOP_BUILDDIR@/Documentation/html/api-html',
+        '@TOP_BUILDDIR@/Documentation/api-html',
+    ],
+    [
+        '@TOP_BUILDDIR@/Documentation/html/internal-api-html',
+        '@TOP_BUILDDIR@/Documentation/internal-api-html',
+    ],
+]
+
 # -- Options for HTML output -------------------------------------------------
 
 # The theme to use for HTML and HTML Help pages.  See the documentation for
diff --git a/Documentation/extensions/doxygen-link.py b/Documentation/extensions/doxygen-link.py
new file mode 100644
index 000000000000..8b94a4dd7f0b
--- /dev/null
+++ b/Documentation/extensions/doxygen-link.py
@@ -0,0 +1,73 @@ 
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (C) 2025, Ideas on Board Oy
+
+import contextlib
+import os
+import shutil
+from pathlib import Path
+from sphinx.util import logging
+
+__version__ = "0.0.0"
+
+logger = logging.getLogger(__name__)
+
+
+def on_config_inited(app, config):
+    entries = []
+
+    outdir = Path(app.outdir).absolute()
+
+    for index, items in enumerate(config.doxygen_links):
+        err_msg_prefix = f'Config variable `doxygen_links` contains invalid entry {index} (`{items}`)'
+
+        if len(items) != 2:
+            raise ValueError(f'{err_msg_prefix}: expected (path, target)')
+
+        path = Path(items[0]).absolute()
+        target = Path(items[1]).relative_to(path.parent, walk_up=True)
+
+        if not path.is_relative_to(outdir):
+            raise ValueError(f'{err_msg_prefix}: path `{items[0]}` is outside of output directory `{outdir}`')
+
+        entries.append([path, target])
+
+    config.doxygen_links = entries
+
+
+def on_builder_inited(app):
+    # Remove the symlinks if they exist, to avoid overwriting the index.html
+    # generated by Doxygen with the placeholder index from Sphinx.
+
+    for path, target in app.config.doxygen_links:
+        if path.is_symlink():
+            logger.info(f'Removing existing symlink {path}')
+            os.unlink(path)
+
+
+def on_build_finished(app, exc):
+    # Create the symlinks. Remove any existing placeholder directory
+    # recursively first.
+
+    if exc:
+        return
+
+    for path, target in app.config.doxygen_links:
+        logger.info(f'Creating symlink {path} -> {target}')
+
+        if path.is_dir():
+            shutil.rmtree(path)
+
+        os.symlink(target, path)
+
+
+def setup(app):
+    app.add_config_value('doxygen_links', [], 'env', frozenset({list, tuple}))
+    app.connect('config-inited', on_config_inited)
+    app.connect('builder-inited', on_builder_inited)
+    app.connect('build-finished', on_build_finished)
+
+    return {
+        "version": __version__,
+        "parallel_read_safe": True,
+        "parallel_write_safe": True,
+    }
diff --git a/Documentation/meson.build b/Documentation/meson.build
index f73407432fff..82d76b257b8c 100644
--- a/Documentation/meson.build
+++ b/Documentation/meson.build
@@ -12,6 +12,7 @@  dot = find_program('dot', required : get_option('documentation'))
 if doxygen.found() and dot.found()
     cdata = configuration_data()
     cdata.set('VERSION', 'v@0@'.format(libcamera_git_version))
+    cdata.set('CURRENT_SRCDIR', meson.current_source_dir())
     cdata.set('TOP_SRCDIR', meson.project_source_root())
     cdata.set('TOP_BUILDDIR', meson.project_build_root())
     cdata.set('OUTPUT_DIR', meson.current_build_dir())
@@ -89,7 +90,7 @@  if doxygen.found() and dot.found()
                                    output : 'api-html',
                                    command : [doxygen, doxyfile],
                                    install : true,
-                                   install_dir : doc_install_dir,
+                                   install_dir : doc_install_dir / 'html',
                                    install_tag : 'doc')
 
     # This is the internal documentation, which hard-codes a list of directories
@@ -109,7 +110,7 @@  if doxygen.found() and dot.found()
                                      output : 'internal-api-html',
                                      command : [doxygen, doxyfile],
                                      install : true,
-                                     install_dir : doc_install_dir,
+                                     install_dir : doc_install_dir / 'html',
                                      install_tag : 'doc-internal')
 endif
 
@@ -149,7 +150,11 @@  if sphinx.found()
     fs = import('fs')
     sphinx_conf_dir = fs.parent(sphinx_conf)
 
+    sphinx_env = environment()
+    sphinx_env.set('PYTHONDONTWRITEBYTECODE', '1')
+
     docs_sources = [
+        'api-html/index.rst',
         'camera-sensor-model.rst',
         'code-of-conduct.rst',
         'coding-style.rst',
@@ -164,6 +169,7 @@  if sphinx.found()
         'guides/pipeline-handler.rst',
         'guides/tracing.rst',
         'index.rst',
+        'internal-api-html/index.rst',
         'introduction.rst',
         'lens_driver_requirements.rst',
         'libcamera_architecture.rst',
@@ -183,10 +189,14 @@  if sphinx.found()
                   input : docs_sources,
                   output : 'html',
                   build_by_default : true,
+                  depend_files : [
+                      'extensions/doxygen-link.py',
+                  ],
                   depends : [
                       doxygen_public,
                       doxygen_internal,
                   ],
+                  env : sphinx_env,
                   install : true,
                   install_dir : doc_install_dir,
                   install_tag : 'doc')
@@ -195,7 +205,8 @@  if sphinx.found()
                   command : [sphinx, '-W', '-b', 'linkcheck',
                              '-c', sphinx_conf_dir,
                              meson.current_source_dir(), '@OUTPUT@'],
-                  build_always_stale : true,
                   input : docs_sources,
-                  output : 'linkcheck')
+                  output : 'linkcheck',
+                  build_always_stale : true,
+                  env : sphinx_env)
 endif