Added rpc.xmlclient backend plugin for forwarding; added corresponding unit tests

2 files changed, 79 insertions, 12 deletions

diff --git a/ipalib/errors2.py b/ipalib/errors2.py
index 4c8acd5d8..7e2eea058 100644
--- a/ipalib/errors2.py
+++ b/ipalib/errors2.py
@@ -275,10 +275,27 @@ class VersionError(PublicError):
     format = _('%(cver)s client incompatible with %(sver)s server at %(server)r')
 
 
+class UnknownError(PublicError):
+    """
+    **902** Raised when client does not know error it caught from server.
+
+    For example:
+
+    >>> raise UnknownError(code=57, server='localhost', error=u'a new error')
+    ...
+    Traceback (most recent call last):
+      ...
+    UnknownError: unknown error 57 from localhost: a new error
+
+    """
+
+    errno = 902
+    format = _('unknown error %(code)d from %(server)s: %(error)s')
+
 
 class InternalError(PublicError):
     """
-    **902** Raised to conceal a non-public exception.
+    **903** Raised to conceal a non-public exception.
 
     For example:
 
@@ -288,7 +305,7 @@ class InternalError(PublicError):
     InternalError: an internal error has occured
     """
 
-    errno = 902
+    errno = 903
     format = _('an internal error has occured')
 
     def __init__(self, message=None):
@@ -300,7 +317,7 @@ class InternalError(PublicError):
 
 class ServerInternalError(PublicError):
     """
-    **903** Raised when client catches an `InternalError` from server.
+    **904** Raised when client catches an `InternalError` from server.
 
     For example:
 
@@ -310,13 +327,13 @@ class ServerInternalError(PublicError):
     ServerInternalError: an internal error has occured on server at 'https://localhost'
     """
 
-    errno = 903
+    errno = 904
     format = _('an internal error has occured on server at %(server)r')
 
 
 class CommandError(PublicError):
     """
-    **904** Raised when an unknown command is called.
+    **905** Raised when an unknown command is called.
 
     For example:
 
@@ -326,13 +343,13 @@ class CommandError(PublicError):
     CommandError: unknown command 'foobar'
     """
 
-    errno = 904
+    errno = 905
     format = _('unknown command %(name)r')
 
 
 class ServerCommandError(PublicError):
     """
-    **905** Raised when client catches a `CommandError` from server.
+    **906** Raised when client catches a `CommandError` from server.
 
     For example:
 
@@ -343,13 +360,13 @@ class ServerCommandError(PublicError):
     ServerCommandError: error on server 'https://localhost': unknown command 'foobar'
     """
 
-    errno = 905
+    errno = 906
     format = _('error on server %(server)r: %(error)s')
 
 
 class NetworkError(PublicError):
     """
-    **906** Raised when a network connection cannot be created.
+    **907** Raised when a network connection cannot be created.
 
     For example:
 
@@ -359,13 +376,13 @@ class NetworkError(PublicError):
     NetworkError: cannot connect to 'ldap://localhost:389'
     """
 
-    errno = 906
+    errno = 907
     format = _('cannot connect to %(uri)r')
 
 
 class ServerNetworkError(PublicError):
     """
-    **907** Raised when client catches a `NetworkError` from server.
+    **908** Raised when client catches a `NetworkError` from server.
 
     For example:
 
@@ -376,7 +393,7 @@ class ServerNetworkError(PublicError):
     ServerNetworkError: error on server 'https://localhost': cannot connect to 'ldap://localhost:389'
     """
 
-    errno = 907
+    errno = 908
     format = _('error on server %(server)r: %(error)s')
 
 
diff --git a/ipalib/rpc.py b/ipalib/rpc.py
index acfdae95d..e7823ef95 100644
--- a/ipalib/rpc.py
+++ b/ipalib/rpc.py
@@ -30,7 +30,11 @@ Also see the `ipaserver.rpcserver` module.
 """
 
 from types import NoneType
+import threading
 from xmlrpclib import Binary, Fault, dumps, loads
+from ipalib.backend import Backend
+from ipalib.errors2 import public_errors, PublicError, UnknownError
+from ipalib.request import context
 
 
 def xml_wrap(value):
@@ -155,3 +159,49 @@ def xml_loads(data):
     """
     (params, method) = loads(data)
     return (xml_unwrap(params), method)
+
+
+class xmlclient(Backend):
+    """
+    Forwarding backend for XML-RPC client.
+    """
+
+    def __init__(self):
+        super(xmlclient, self).__init__()
+        self.__errors = dict((e.errno, e) for e in public_errors)
+
+    def forward(self, name, *args, **kw):
+        """
+        Forward call to command named ``name`` over XML-RPC.
+
+        This method will encode and forward an XML-RPC request, and will then
+        decode and return the corresponding XML-RPC response.
+
+        :param command: The name of the command being forwarded.
+        :param args: Positional arguments to pass to remote command.
+        :param kw: Keyword arguments to pass to remote command.
+        """
+        if name not in self.Command:
+            raise ValueError(
+                '%s.forward(): %r not in api.Command' % (self.name, name)
+            )
+        if not hasattr(context, 'xmlconn'):
+            raise StandardError(
+                '%s.forward(%r): need context.xmlconn in thread %r' % (
+                    self.name, name, threading.currentThread().getName()
+                )
+            )
+        command = getattr(context.xmlconn, name)
+        params = args + (kw,)
+        try:
+            response = command(xml_wrap(params))
+            return xml_unwrap(response)
+        except Fault, e:
+            if e.faultCode in self.__errors:
+                error = self.__errors[e.faultCode]
+                raise error(message=e.faultString)
+            raise UnknownError(
+                code=e.faultCode,
+                error=e.faultString,
+                server=self.env.xmlrpc_uri,
+            )