sync: Support manual authentication to the manifest server

Add two new command line options, -u/--manifest-server-username and
-p/--manifest-server-password, which can be used to specify a username
and password to authenticate to the manifest server when using the
-s/--smart-sync or -t/--smart-tag option.

If -u and -p are not specified when using the -s or -t option, use
authentication credentials from the .netrc file (if there are any).

Authentication credentials from -u/-p or .netrc are not used if the
manifest server specified in the manifest file already includes
credentials.

Change-Id: I6cf9540d28f6cef64c5694e8928cfe367a71d28d

subcmds/sync.py

@@ -83,6 +83,18 @@ build as specified by the manifest-server element in the current
 manifest. The -t/--smart-tag option is similar and allows you to
 specify a custom tag/label.
 
+The -u/--manifest-server-username and -p/--manifest-server-password
+options can be used to specify a username and password to authenticate
+with the manifest server when using the -s or -t option.
+
+If -u and -p are not specified when using the -s or -t option, '%prog'
+will attempt to read authentication credentials for the manifest server
+from the user's .netrc file.
+
+'%prog' will not use authentication credentials from -u/-p or .netrc
+if the manifest server specified in the manifest file already includes
+credentials.
+
 The -f/--force-broken option can be used to proceed with syncing
 other projects if a project sync fails.
 
@@ -159,6 +171,12 @@ later is required to fix a server side protocol bug.
       p.add_option('-t', '--smart-tag',
                    dest='smart_tag', action='store',
                    help='smart sync using manifest from a known tag')
+      p.add_option('-u', '--manifest-server-username', action='store',
+                   dest='manifest_server_username',
+                   help='username to authenticate with the manifest server')
+      p.add_option('-p', '--manifest-server-password', action='store',
+                   dest='manifest_server_password',
+                   help='password to authenticate with the manifest server')
 
     g = p.add_option_group('repo Version options')
     g.add_option('--no-repo-verify',
@@ -358,6 +376,14 @@ uncommitted changes are present' % project.relpath
     if opt.manifest_name and opt.smart_tag:
       print >>sys.stderr, 'error: cannot combine -m and -t'
       sys.exit(1)
+    if opt.manifest_server_username or opt.manifest_server_password:
+      if not (opt.smart_sync or opt.smart_tag):
+        print >>sys.stderr, 'error: -u and -p may only be combined with ' \
+                            '-s or -t'
+        sys.exit(1)
+      if None in [opt.manifest_server_username, opt.manifest_server_password]:
+        print >>sys.stderr, 'error: both -u and -p must be given'
+        sys.exit(1)
 
     if opt.manifest_name:
       self.manifest.Override(opt.manifest_name)
@@ -369,7 +395,14 @@ uncommitted changes are present' % project.relpath
         sys.exit(1)
 
       manifest_server = self.manifest.manifest_server
+
       if not '@' in manifest_server:
+        username = None
+        password = None
+        if opt.manifest_server_username and opt.manifest_server_password:
+          username = opt.manifest_server_username
+          password = opt.manifest_server_password
+        else:
           try:
             info = netrc.netrc()
           except IOError:
@@ -385,9 +418,9 @@ uncommitted changes are present' % project.relpath
               # in the .netrc file.
               print >>sys.stderr, 'No credentials found for %s in .netrc' % \
                                   parse_result.hostname
-          except netrc.NetrcParseError as e:
+            except netrc.NetrcParseError, e:
               print >>sys.stderr, 'Error parsing .netrc file: %s' % e
-          else:
+
         if (username and password):
           manifest_server = manifest_server.replace('://', '://%s:%s@' %
                                                     (username, password),