devserver: better handling of archive directory

devserver.py

 #!/usr/bin/python
 
 # Copyright (c) 2009-2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """A CherryPy-based webserver to host images and build packages."""
 
 import cherrypy
 import optparse
@@ skipping 38 matching lines @@
                     'tools.staticdir.on': True,
                     'response.timeout': 10000,
                   },
                 }
   if options.production:
     base_config['global']['server.environment'] = 'production'
 
   return base_config
 
 
-def _PrepareToServeUpdatesOnly(image_dir):
+def _PrepareToServeUpdatesOnly(image_dir, static_dir):
   """Sets up symlink to image_dir for serving purposes."""
   assert os.path.exists(image_dir), '%s must exist.' % image_dir
   # If  we're  serving  out  of  an archived  build  dir  (e.g.  a
   # buildbot), prepare this webserver's magic 'static/' dir with a
   # link to the build archive.
   cherrypy.log('Preparing autoupdate for "serve updates only" mode.',
                'DEVSERVER')
-  if os.path.lexists('static/archive'):
-    if image_dir != os.readlink('static/archive'):
+  if os.path.lexists('%s/archive' % static_dir):
+    if image_dir != os.readlink('%s/archive' % static_dir):
       cherrypy.log('removing stale symlink to %s' % image_dir, 'DEVSERVER')
-      os.unlink('static/archive')
-      os.symlink(image_dir, 'static/archive')
+      os.unlink('%s/archive' % static_dir)
+      os.symlink(image_dir, '%s/archive' % static_dir)
   else:
-    os.symlink(image_dir, 'static/archive')
+    os.symlink(image_dir, '%s/archive' % static_dir)
   cherrypy.log('archive dir: %s ready to be used to serve images.' % image_dir,
                'DEVSERVER')
 
 
 class DevServerRoot(object):
   """The Root Class for the Dev Server.
 
   CherryPy works as follows:
     For each method in this class, cherrpy interprets root/path
     as a call to an instance of DevServerRoot->method_name.  For example,
@@ skipping 69 matching lines @@
   parser.add_option('--validate_factory_config', action="store_true",
                     dest='validate_factory_config',
                     help='Validate factory config file, then exit.')
   parser.set_usage(parser.format_help())
   (options, _) = parser.parse_args()
 
   devserver_dir = os.path.dirname(os.path.abspath(sys.argv[0]))
   root_dir = os.path.realpath('%s/../..' % devserver_dir)
   serve_only = False
 
+  static_dir = os.path.realpath('%s/static' % options.data_dir)
+  os.system('mkdir -p %s' % static_dir)
+
   if options.archive_dir:
-    static_dir = os.path.realpath(options.archive_dir)
-    _PrepareToServeUpdatesOnly(static_dir)
+  # FIXME(zbehan) Legacy support:

[sosa, 2011/02/18 22:24:42]

TODO(zbehan):  Remove legacy support rather than FIXME

+  #  archive_dir is the directory where static/archive will point.
+  #  If this is an absolute path, all is fine. If someone calls this
+  #  using a relative path, that is relative to src/platform/dev/.
+  #  That use case is unmaintainable, but since applications use it
+  #  with =./static, instead of a boolean flag, we'll make this relative
+  #  to devserver_dir  to keep these unbroken. For now.
+    prev_cwd = os.getcwd()
+    os.chdir(devserver_dir) # this surely exists

[sosa, 2011/02/18 22:24:42]

I'd prefer if you checked if that path was relative path than chdir

+    archive_dir = os.path.realpath(options.archive_dir)
+    _PrepareToServeUpdatesOnly(archive_dir, static_dir)
     serve_only = True
-  else:
-    static_dir = os.path.realpath('%s/static' % options.data_dir)
-    os.system('mkdir -p %s' % static_dir)
+    os.chdir(prev_cwd)
 
   cache_dir = os.path.join(static_dir, 'cache')
   cherrypy.log('Using cache directory %s' % cache_dir, 'DEVSERVER')
 
   if os.path.exists(cache_dir):
     if options.clear_cache:
       # Clear the cache and exit on error.
       if os.system('rm -rf %s/*' % cache_dir) != 0:
         cherrypy.log('Failed to clear the cache with %s' % cmd,
                      'DEVSERVER')
@@ skipping 43 matching lines @@
     # We don't run the dev server with this option.
     if options.validate_factory_config:
       sys.exit(0)
   elif options.pregenerate_update:
     if not updater.PreGenerateUpdate():
       sys.exit(1)
 
   # If the command line requested after setup, it's time to do it.
   if not options.exit:
     cherrypy.quickstart(DevServerRoot(), config=_GetConfig(options))