The commit consists of:

1) Support metadata (e.g. get-depth) for rpc request.
2) Support parameters in rpc requests
3) Generate the code for netconf rpc to Voltha grpc mapping
4) Initial Support custom rpc requests (those defined in the voltha YANG schemas).

Change-Id: I24dc7fd75b5f71d0d8591637579672b25fda57ec
diff --git a/netconf/nc_rpc/ext/get_schema.py b/netconf/nc_rpc/ext/get_schema.py
index 569a3b0..a90906e 100644
--- a/netconf/nc_rpc/ext/get_schema.py
+++ b/netconf/nc_rpc/ext/get_schema.py
@@ -26,8 +26,8 @@
 
 class GetSchema(Rpc):
     def __init__(self, request, request_xml, grpc_client, session, capabilities):
-        super(GetSchema, self).__init__(request, request_xml, grpc_client, session)
-        self.capabilities = capabilities
+        super(GetSchema, self).__init__(request, request_xml, grpc_client,
+                                        session, capabilities)
         # specific schema parsing required
         self.parse_schema_request(request_xml)
         self._validate_parameters()
diff --git a/netconf/nc_rpc/ext/get_schemas.py b/netconf/nc_rpc/ext/get_schemas.py
index cc09ebb..094c8df 100644
--- a/netconf/nc_rpc/ext/get_schemas.py
+++ b/netconf/nc_rpc/ext/get_schemas.py
@@ -26,9 +26,9 @@
 
 class GetSchemas(Rpc):
     def __init__(self, request, request_xml, grpc_client, session, capabilities):
-        super(GetSchemas, self).__init__(request, request_xml, grpc_client, session)
+        super(GetSchemas, self).__init__(request, request_xml, grpc_client,
+                                         session, capabilities)
         self._validate_parameters()
-        self.capabilities = capabilities
 
     @inlineCallbacks
     def execute(self):
diff --git a/netconf/nc_rpc/ext/get_voltha.py b/netconf/nc_rpc/ext/get_voltha.py
deleted file mode 100644
index 5b004e7..0000000
--- a/netconf/nc_rpc/ext/get_voltha.py
+++ /dev/null
@@ -1,66 +0,0 @@
-#!/usr/bin/env python
-#
-# Copyright 2017 the original author or authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-from lxml import etree
-import structlog
-from netconf.nc_rpc.rpc import Rpc
-import netconf.nc_common.error as ncerror
-from twisted.internet.defer import inlineCallbacks, returnValue
-import dicttoxml
-
-log = structlog.get_logger()
-
-
-class GetVoltha(Rpc):
-    def __init__(self, request, request_xml, grpc_client, session, capabilities):
-        super(GetVoltha, self).__init__(request, request_xml, grpc_client, session)
-        self._validate_parameters()
-
-
-    @inlineCallbacks
-    def execute(self):
-        log.info('get-voltha-request', session=self.session.session_id,
-                 method=self.rpc_method)
-        if self.rpc_response.is_error:
-            returnValue(self.rpc_response)
-
-        # Invoke voltha via the grpc client
-        res_dict = yield self.grpc_client.invoke_voltha_api(self.voltha_method_ref)
-
-        # convert dict to xml
-        xml = dicttoxml.dicttoxml(res_dict, attr_type=False)
-        log.info('voltha-info', res=res_dict, xml=xml)
-
-        root_elem = self.get_root_element(xml)
-        root_elem.tag = 'data'
-
-        self.rpc_method.append(root_elem)
-        self.rpc_response.node = self.rpc_method
-        self.rpc_response.is_error = False
-
-        returnValue(self.rpc_response)
-
-
-    def _validate_parameters(self):
-        log.info('validate-parameters', session=self.session.session_id)
-        self.params = self.rpc_method.getchildren()
-        if len(self.params) > 1:
-            self.rpc_response.is_error = True
-            self.rpc_response.node = ncerror.BadMsg(self.rpc_request)
-            return
-
-        if not self.params:
-            self.params = [None]
diff --git a/netconf/nc_rpc/ext/voltha_rpc.py b/netconf/nc_rpc/ext/voltha_rpc.py
new file mode 100644
index 0000000..37ba305
--- /dev/null
+++ b/netconf/nc_rpc/ext/voltha_rpc.py
@@ -0,0 +1,117 @@
+#!/usr/bin/env python
+#
+# Copyright 2017 the original author or authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+import structlog
+from netconf.nc_rpc.rpc import Rpc
+import netconf.nc_common.error as ncerror
+from twisted.internet.defer import inlineCallbacks, returnValue
+import dicttoxml
+from netconf.nc_common.utils import qmap, ns
+from netconf.constants import Constants as C
+from netconf.grpc_client.nc_rpc_mapper import \
+    get_nc_rpc_mapper_instance
+
+log = structlog.get_logger()
+
+
+class VolthaRpc(Rpc):
+    def __init__(self, request, request_xml, grpc_client, session,
+                 capabilities):
+        super(VolthaRpc, self).__init__(request, request_xml, grpc_client,
+                                        session, capabilities)
+        self.service = None
+        self.method = None
+        self.metadata = None
+        self._extract_parameters()
+        if not self.rpc_response.is_error:
+            self._validate_parameters()
+
+    @inlineCallbacks
+    def execute(self):
+        if self.rpc_response.is_error:
+            returnValue(self.rpc_response)
+
+        log.info('voltha-rpc-request', session=self.session.session_id,
+                 request=self.request)
+
+        # Execute the request
+        res_dict = yield self.grpc_client.invoke_voltha_rpc(
+            service=self.service,
+            method=self.method,
+            params=self.request['params'],
+            metadata=self.metadata)
+
+        # convert dict to xml
+        xml = dicttoxml.dicttoxml(res_dict, attr_type=True)
+        log.info('voltha-info', res=res_dict, xml=xml)
+
+        root_elem = self.get_root_element(xml)
+
+        # Build the yang response
+        self.rpc_response.node = self.rpc_response.build_yang_response(
+            root_elem, self.request, custom_rpc=True)
+        self.rpc_response.is_error = False
+
+        returnValue(self.rpc_response)
+
+    def _validate_parameters(self):
+        log.info('validate-parameters', session=self.session.session_id)
+        # For now just validate that the command is presenf
+        if self.request:
+            try:
+                if self.request['command'] is None:
+                    self.rpc_response.is_error = True
+                    self.rpc_response.node = ncerror.BadMsg(self.request_xml)
+                    return
+
+            except Exception as e:
+                self.rpc_response.is_error = True
+                self.rpc_response.node = ncerror.ServerException(
+                    self.request_xml)
+                return
+
+    def _extract_parameters(self):
+        try:
+            rpc_node = self.request_xml.find(''.join(
+                [qmap(C.VOLTHA),
+                 self.request['command']])
+            )
+            self.request['params'] = {}
+            if rpc_node is not None:
+                for r in rpc_node:
+                    self.request['params'][
+                        r.tag.replace(qmap(C.VOLTHA), "")] = r.text
+
+            # Remove the subclass element in the request if it is present as
+            # it is not required for rpc calls
+            if self.request.has_key('subclass'):
+                self.request.pop('subclass', None)
+
+            # Extract the service and method from the rpc command
+            command = self.request['command'].split('-')
+            if len(command) != 2:
+                log.debug('invalid-format', command=self.request['command'])
+                raise
+
+            self.service = command[0]
+            self.method = command[1]
+            if self.request.has_key('metadata'):
+                self.metadata = self.request['metadata']
+
+        except Exception as e:
+            self.rpc_response.is_error = True
+            self.rpc_response.node = ncerror.BadMsg(self.request_xml)
+            log.exception('params-parsing-error', xml=self.request_xml, e=e)