conf: add a hack to make httpdomain routing table referencable

this aims at eliminating a warning generated by sphinx-build on swh-web's
index, due to the presence of an explicit link to the http-routingtable.html
file (which does not exists at that time, thus generated a warning).

This should be killed once

  https://github.com/sphinx-contrib/httpdomain/pull/19

is accepted and released.

swh/docs/sphinx/conf.py

@@ -131,9 +131,25 @@ modindex_common_prefix = ['swh.']
 extlinks = {}
 
 
+# XXX Kill this ASA this PR is accepted and released
+# https://github.com/sphinx-contrib/httpdomain/pull/19
+def register_routingtable_as_label(app, document):
+    from sphinx.locale import _  # noqa
+    labels = app.env.domaindata['std']['labels']
+    labels['routingtable'] = 'http-routingtable', '', _('HTTP Routing Table')
+    anonlabels = app.env.domaindata['std']['anonlabels']
+    anonlabels['routingtable'] = 'http-routingtable', ''
+
+
 # hack to set the adequate django settings when building global swh doc
 # to avoid autodoc build errors
 def setup(app):
     os.environ.setdefault('DJANGO_SETTINGS_MODULE',
                           'swh.docs.django_settings')
     django.setup()
+    import pkg_resources  # noqa
+    from distutils.version import StrictVersion  # noqa
+
+    httpdomain = pkg_resources.get_distribution('sphinxcontrib-httpdomain')
+    if StrictVersion(httpdomain.version) <= StrictVersion('1.7.0'):
+        app.connect('doctree-read', register_routingtable_as_label)