xref: /linux/Documentation/sphinx/translations.py (revision 79790b6818e96c58fe2bffee1b418c16e64e7b80) 
1# SPDX-License-Identifier: GPL-2.0
2#
3# Copyright © 2023, Oracle and/or its affiliates.
4# Author: Vegard Nossum <vegard.nossum@oracle.com>
5#
6# Add translation links to the top of the document.
7#
8
9import os
10
11from docutils import nodes
12from docutils.transforms import Transform
13
14import sphinx
15from sphinx import addnodes
16from sphinx.errors import NoUri
17
18all_languages = {
19    # English is always first
20    None: 'English',
21
22    # Keep the rest sorted alphabetically
23    'zh_CN': 'Chinese (Simplified)',
24    'zh_TW': 'Chinese (Traditional)',
25    'it_IT': 'Italian',
26    'ja_JP': 'Japanese',
27    'ko_KR': 'Korean',
28    'sp_SP': 'Spanish',
29}
30
31class LanguagesNode(nodes.Element):
32    pass
33
34class TranslationsTransform(Transform):
35    default_priority = 900
36
37    def apply(self):
38        app = self.document.settings.env.app
39        docname = self.document.settings.env.docname
40
41        this_lang_code = None
42        components = docname.split(os.sep)
43        if components[0] == 'translations' and len(components) > 2:
44            this_lang_code = components[1]
45
46            # normalize docname to be the untranslated one
47            docname = os.path.join(*components[2:])
48
49        new_nodes = LanguagesNode()
50        new_nodes['current_language'] = all_languages[this_lang_code]
51
52        for lang_code, lang_name in all_languages.items():
53            if lang_code == this_lang_code:
54                continue
55
56            if lang_code is None:
57                target_name = docname
58            else:
59                target_name = os.path.join('translations', lang_code, docname)
60
61            pxref = addnodes.pending_xref('', refdomain='std',
62                reftype='doc', reftarget='/' + target_name, modname=None,
63                classname=None, refexplicit=True)
64            pxref += nodes.Text(lang_name)
65            new_nodes += pxref
66
67        self.document.insert(0, new_nodes)
68
69def process_languages(app, doctree, docname):
70    for node in doctree.traverse(LanguagesNode):
71        if app.builder.format not in ['html']:
72            node.parent.remove(node)
73            continue
74
75        languages = []
76
77        # Iterate over the child nodes; any resolved links will have
78        # the type 'nodes.reference', while unresolved links will be
79        # type 'nodes.Text'.
80        languages = list(filter(lambda xref:
81            isinstance(xref, nodes.reference), node.children))
82
83        html_content = app.builder.templates.render('translations.html',
84            context={
85                'current_language': node['current_language'],
86                'languages': languages,
87            })
88
89        node.replace_self(nodes.raw('', html_content, format='html'))
90
91def setup(app):
92    app.add_node(LanguagesNode)
93    app.add_transform(TranslationsTransform)
94    app.connect('doctree-resolved', process_languages)
95
96    return {
97        'parallel_read_safe': True,
98        'parallel_write_safe': True,
99    }
100