loman: Add support for adding elements from default.xml

bin/loman.py

Index: bin/loman.py
diff --git a/bin/loman.py b/bin/loman.py
index ddb6d6d621f2771226ae327d472fa1f42f26fee1..0ae74e685e094e85ec66e87dea58f20431680ac3 100755
--- a/bin/loman.py
+++ b/bin/loman.py
@@ -24,6 +24,17 @@ def _FindRepoDir():
   return None
 
 
+def _ReadManifest(manifest, err_not_found=False):
+  if os.path.isfile(manifest):
+    ptree = LocalManifest(open(manifest).read())
+  elif err_not_found:
+    Die('Manifest file, %s, not found' % manifest)
+  else:
+    ptree = LocalManifest()
+  ptree.Parse()
+  return ptree
+
+
 class LocalManifest:
   """Class which provides an abstraction for manipulating the local manifest."""
 
@@ -34,63 +45,92 @@ class LocalManifest:
     """Parse the manifest."""
     self._root = ElementTree.fromstring(self._text)
 
-  def AddWorkonProject(self, name, path):
-    """Add a new workon project if it is not already in the manifest.
+  def AddProjectElement(self, element, workon='False'):
+    """Add a new project element to the manifest tree.
 
     Returns:
       True on success.
     """
-
+    name = element.attrib['name']
+    path = element.attrib['path']
     for project in self._root.findall('project'):
         if project.attrib['path'] == path or project.attrib['name'] == name:
           if project.attrib['path'] == path and project.attrib['name'] == name:
             return True
           else:
             return False
-    self._AddProject(name, path, workon='True')
-    return True
-
-  def _AddProject(self, name, path, workon='False'):
-    element = ElementTree.Element('project', name=name, path=path,
-                                  workon=workon)
+    element.attrib['workon'] = workon
     element.tail = '\n'
     self._root.append(element)
+    return True
+
+  def AddProject(self, name, path, workon='False'):
+    """Add a workon project if it is not already in the manifest.
+
+    Returns:
+      True on success.
+    """
+    element = ElementTree.Element('project', name=name, path=path)
+    return self.AddProjectElement(element, workon=workon)
+
+  def AddWorkonProjectElement(self, element):
+    return self.AddProjectElement(element, workon='True')
+
+  def AddWorkonProject(self, name, path):
+    return self.AddProject(name, path, workon='True')
+
+  def GetProject(self, name):
+    """Accessor method for getting a project node from the manifest tree.
+
+    Returns:
+      project element node from ElementTree, otherwise, None
+    """
+
+    for project in self._root.findall('project'):
+      if project.attrib['name'] == name:
+        return project
+    return None
 
   def ToString(self):
     return ElementTree.tostring(self._root, encoding='UTF-8')
 
 
 def main(argv):
-  usage = 'usage: %prog add [options] <name> <path>'
+  repo_dir = _FindRepoDir()
+  if not repo_dir:
+    Die("Unable to find repo dir.")
+
+  usage = 'usage: %prog add [options] <name>'
   parser = optparse.OptionParser(usage=usage)
   parser.add_option('-w', '--workon', action='store_true', dest='workon',
                     default=False, help='Is this a workon package?')
-  parser.add_option('-f', '--file', dest='manifest',
+  parser.add_option('-f', '--file', dest='local_manifest',
+                    default='%s/local_manifest.xml' % repo_dir,
                     help='Non-default manifest file to read.')
+  parser.add_option('-d', '--default', dest='full_manifest',
+                    default='%s/manifests/full.xml' % repo_dir,
+                    help='Default manifest file to read.')
   (options, args) = parser.parse_args(argv[2:])
-  if len(args) < 2:
+  if len(args) < 1:
       parser.error('Not enough arguments')
   if argv[1] not in ['add']:
       parser.error('Unsupported command: %s.' % argv[1])
   if not options.workon:
       parser.error('Adding of non-workon projects is currently unsupported.')
-  (name, path) = (args[0], args[1])
+  name = args[0]
+
+  local_tree = _ReadManifest(options.local_manifest)
+  full_tree = _ReadManifest(options.full_manifest)
+
+  project_element = full_tree.GetProject(name)
+  if project_element == None:
+    Die('No project named, %s, in the default manifest.' % name)
+  success = local_tree.AddWorkonProjectElement(project_element)
+  if not success:
+    Die('name "%s" already exits with a different path.' % name)
 
-  repo_dir = _FindRepoDir()
-  if not repo_dir:
-    Die("Unable to find repo dir.")
-  local_manifest = options.manifest or \
-    os.path.join(_FindRepoDir(), 'local_manifest.xml')
-  if os.path.isfile(local_manifest):
-    ptree = LocalManifest(open(local_manifest).read())
-  else:
-    ptree = LocalManifest()
-  ptree.Parse()
-  if not ptree.AddWorkonProject(name, path):
-      Die('Path "%s" or name "%s" already exits in the manifest.' %
-          (path, name))
   try:
-    print >> open(local_manifest, 'w'), ptree.ToString()
+    print >> open(options.local_manifest, 'w'), local_tree.ToString()
   except Exception, e:
     Die('Error writing to manifest: %s' % e)