1 files changed, 93 insertions, 0 deletions
diff --git a/distbuild/protocol.py b/distbuild/protocol.py
new file mode 100644
index 00000000..5d693761
--- /dev/null
+++ b/distbuild/protocol.py
@@ -0,0 +1,93 @@
+# distbuild/protocol.py -- abstractions for the JSON messages
+#
+# Copyright (C) 2014  Codethink Limited
+# 
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; version 2 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA..
+
+
+'''Construct protocol message objects (dicts).'''
+
+
+_types = {
+    'build-request': [
+        'id',
+        'repo',
+        'ref',
+        'morphology',
+    ],
+    'build-progress': [
+        'id',
+        'message',
+    ],
+    'build-steps': [
+        'id',
+        'steps',
+    ],
+    'step-started': [
+        'id',
+        'step_name',
+        'worker_name',
+    ],
+    'step-output': [
+        'id',
+        'step_name',
+        'stdout',
+        'stderr',
+    ],
+    'step-finished': [
+        'id',
+        'step_name',
+    ],
+    'step-failed': [
+        'id',
+        'step_name',
+    ],
+    'build-finished': [
+        'id',
+        'urls',
+    ],
+    'build-failed': [
+        'id',
+        'reason',
+    ],
+    'exec-request': [
+        'id',
+        'argv',
+        'stdin_contents',
+    ],
+    'exec-cancel': [
+        'id',
+    ],
+    'http-request': [
+        'id',
+        'url',
+        'method',
+    ],
+}
+
+
+def message(message_type, **kwargs):
+    assert message_type in _types
+    required_fields = _types[message_type]
+
+    for name in required_fields:
+        assert name in kwargs, 'field %s is required' % name
+
+    for name in kwargs:
+        assert name in required_fields, 'field %s is not allowed' % name
+
+    msg = dict(kwargs)
+    msg['type'] = message_type
+    return msg
+