Switch client to JSON-RPC

Modify ipalib.rpc to support JSON-RPC in addition to XML-RPC.
This is done by subclassing and extending xmlrpclib, because
our existing code relies on xmlrpclib internals.

The URI to use is given in the new jsonrpc_uri env variable. When
it is not given, it is generated from xmlrpc_uri by replacing
/xml with /json.

The rpc_json_uri env variable existed before, but was unused,
undocumented and not set the install scripts.
This patch removes it in favor of jsonrpc_uri (for consistency
with xmlrpc_uri).

Add the rpc_protocol env variable to control the protocol
IPA uses. rpc_protocol defaults to 'jsonrpc', but may be changed
to 'xmlrpc'.
Make backend.Executioner and tests use the backend specified by
rpc_protocol.

For compatibility with unwrap_xml, decoding JSON now gives tuples
instead of lists.

Design: http://freeipa.org/page/V3/JSON-RPC
Ticket: https://fedorahosted.org/freeipa/ticket/3299

1 files changed, 50 insertions, 0 deletions

diff --git a/ipalib/plugins/rpcclient.py b/ipalib/plugins/rpcclient.py
new file mode 100644
index 000000000..6010b8dda
--- /dev/null
+++ b/ipalib/plugins/rpcclient.py
@@ -0,0 +1,50 @@
+# Authors:
+#   Jason Gerard DeRose <jderose@redhat.com>
+#   Rob Crittenden <rcritten@redhat.com>
+#   Petr Viktorin <pviktori@redhat.com>
+#
+# Copyright (C) 2008-2013  Red Hat
+# see file 'COPYING' for use and warranty information
+#
+# 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, either version 3 of the License, or
+# (at your option) any later version.
+#
+# 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, see <http://www.gnu.org/licenses/>.
+
+"""
+RPC client plugins.
+"""
+
+from ipalib import api
+
+if 'in_server' in api.env and api.env.in_server is False:
+    from ipalib.rpc import xmlclient, jsonclient
+    api.register(xmlclient)
+    api.register(jsonclient)
+
+    # FIXME: api.register only looks at the class name, so we need to create
+    # trivial subclasses with the desired name.
+    if api.env.rpc_protocol == 'xmlrpc':
+
+        class rpcclient(xmlclient):
+            """xmlclient renamed to 'rpcclient'"""
+            pass
+        api.register(rpcclient)
+
+    elif api.env.rpc_protocol == 'jsonrpc':
+
+        class rpcclient(jsonclient):
+            """jsonclient renamed to 'rpcclient'"""
+            pass
+        api.register(rpcclient)
+
+    else:
+        raise ValueError('unknown rpc_protocol: %s' % api.env.rpc_protocol)