Changes to support docfx

Note: This requires a patch on the docfx executable, the hashbang line is
missing, creating an execution failure

This makes the executed command docfx, instead of BuildMeta. It adds some error
checking and reporting to output as well.

This is a work in progress, the output format seems to have changed again.

autoapi/mappers/dotnet.py

@@ -1,6 +1,6 @@
 import os
-from collections import defaultdict
 import subprocess
+from collections import defaultdict
 
 import yaml
 from sphinx.util.osutil import ensuredir
@@ -26,9 +26,20 @@ class DotNetSphinxMapper(SphinxMapperBase):
 
         '''
         for path in self.find_files(patterns=patterns, dir=dir, ignore=ignore):
-            subprocess.check_output(['BuildMeta', '/target:Build', path])
+            try:
+                proc = subprocess.Popen(
+                    ['docfx', 'metadata', '--raw', path],
+                    stdout=subprocess.PIPE,
+                    stderr=subprocess.PIPE,
+                    env=dict((key, os.environ[key])
+                              for key in ['PATH', 'DNX_PATH', 'HOME']))
+                _, error_output = proc.communicate()
+                if error_output:
+                    self.app.warn(error_output)
+            except (OSError, subprocess.CalledProcessError) as e:
+                self.app.warn('Error generating metadata: {0}'.format(e))
         # We now have yaml files
-        for xdoc_path in self.find_files(patterns=['*.yml'], dir='xdoc', ignore=ignore):
+        for xdoc_path in self.find_files(patterns=['*.yml'], dir='_api_', ignore=ignore):
             data = self.read_file(path=xdoc_path)
             if data:
                 self.paths[xdoc_path] = data