Solve the error: 'Sphinx' object has no attribute 'info'

This problem has been discussed in this web:
http://lists.openstack.org/pipermail/openstack-discuss/2019-April/004462.html

This solution like nova:
https://review.openstack.org/#/c/648670/

Change-Id: I15e8d731417c041499338ada29c1b7fe5f0715f4

doc/source/conf.py

@@ -33,7 +33,7 @@ extensions = ['redirect',
               'sphinx.ext.todo',
               'sphinx.ext.viewcode',
               'sphinx.ext.mathjax',
-              'oslosphinx',
+              'openstackdocstheme',
               'yasfb',
              ]
 
@@ -103,7 +103,7 @@ man_pages = []
 
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
-html_theme = 'nature'
+html_theme = 'openstackdocs'
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the

doc/source/redirect.py

@@ -5,15 +5,9 @@
 
 import os.path
 
-from sphinx.application import ENV_PICKLE_FILENAME
-from sphinx.util.console import bold
+from sphinx.util import logging
 
-
-def setup(app):
-    from sphinx import application
-    if not isinstance(app, application.Sphinx):
-        return
-    app.connect('build-finished', emit_redirects)
+LOG = logging.getLogger(__name__)
 
 
 def process_redirect_file(app, path, ent):
@@ -35,7 +29,7 @@ def process_redirect_file(app, path, ent):
 
 
 def emit_redirects(app, exc):
-    app.builder.info(bold('scanning %s for redirects...') % app.builder.srcdir)
+    LOG.info('scanning %s for redirects...', app.builder.srcdir)
 
     def process_directory(path):
         for ent in os.listdir(path):
@@ -43,8 +37,12 @@ def emit_redirects(app, exc):
             if os.path.isdir(p):
                 process_directory(p)
             elif ent == 'redirects':
-                app.builder.info('   found redirects at %s' % p)
+                LOG.info('   found redirects at %s' % p)
                 process_redirect_file(app, path, ent)
 
     process_directory(app.builder.srcdir)
-    app.builder.info('...done')
+    LOG.info('...done')
+
+
+def setup(app):
+    app.connect('build-finished', emit_redirects)

requirements.txt

@@ -1,6 +1,5 @@
-oslosphinx
 pbr>=2.0.0,!=2.1.0 # Apache-2.0
 sphinx>=1.6.2 # BSD
 testtools>=1.4.0
-yasfb>=0.5.1
-doc8 # Apache-2.0
+yasfb>=0.8.0
+openstackdocstheme>=1.19.0 # Apache-2.0