141 - Support for Package Management in SO

[osm/SO.git] / common / python / rift / mano / dts / rpc / core.py

diff --git a/common/python/rift/mano/dts/rpc/core.py b/common/python/rift/mano/dts/rpc/core.py
new file mode 100644 (file)
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+++ b/common/python/rift/mano/dts/rpc/core.py
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+"""
+#
+#   Copyright 2016 RIFT.IO Inc
+#
+#   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.
+#
+
+@file core.py
+@author Varun Prasad (varun.prasad@riftio.com)
+@date 28-Sep-2016
+
+"""
+
+import abc
+import asyncio
+
+import gi
+gi.require_version("RwDts", "1.0")
+
+from gi.repository import RwDts as rwdts
+import rift.tasklets
+
+from ..core import DtsHandler
+
+
+class AbstractRpcHandler(DtsHandler):
+    """Base class to simplify RPC implementation
+    """
+    def __init__(self, log, dts, loop):
+        super().__init__(log, dts, loop)
+
+        if not asyncio.iscoroutinefunction(self.callback):
+            raise ValueError('%s has to be a coroutine' % (self.callback))
+
+    @abc.abstractproperty
+    def xpath(self):
+        pass
+
+    @property
+    def input_xpath(self):
+        return "I,{}".format(self.xpath)
+
+    @property
+    def output_xpath(self):
+        return "O,{}".format(self.xpath)
+
+    def flags(self):
+        return rwdts.Flag.PUBLISHER
+
+    @asyncio.coroutine
+    def on_prepare(self, xact_info, action, ks_path, msg):
+        assert action == rwdts.QueryAction.RPC
+
+        try:
+            rpc_op = yield from self.callback(ks_path, msg)
+            xact_info.respond_xpath(
+                rwdts.XactRspCode.ACK,
+                self.output_xpath,
+                rpc_op)
+
+        except Exception as e:
+            self.log.exception(e)
+            xact_info.respond_xpath(
+                rwdts.XactRspCode.NACK,
+                self.output_xpath)
+
+    @asyncio.coroutine
+    def register(self):
+        reg_event = asyncio.Event(loop=self.loop)
+
+        @asyncio.coroutine
+        def on_ready(regh, status):
+            reg_event.set()
+
+        handler = rift.tasklets.DTS.RegistrationHandler(
+                on_prepare=self.on_prepare,
+                on_ready=on_ready)
+
+        with self.dts.group_create() as group:
+            self.reg = group.register(
+                  xpath=self.input_xpath,
+                  handler=handler,
+                  flags=self.flags())
+
+        yield from reg_event.wait()
+
+    @abc.abstractmethod
+    @asyncio.coroutine
+    def callback(self, ks_path, msg):
+        """Subclass needs to override this method
+
+        Args:
+            ks_path : Key spec path
+            msg : RPC input
+        """
+        pass
+