This commit consists of the following:
1) The kafka messaging proxy in Twisted python for adapters
2) Initial implementation and containerization of ponsim OLT adapter
and ponsim ONU adapter
3) Initial submission of request and response facade in both Twisted
python and Go Language
4) Initial implementation of device management and logical device management
in the Core
5) Update to the log module to allow dynamic setting of log level per
package using the gRPC API
6) Bug fixes and minor changes
Change-Id: Ia8f033da84cfd08275335bae9542802415e7bb0f
diff --git a/adapters/common/utils/grpc_utils.py b/adapters/common/utils/grpc_utils.py
new file mode 100644
index 0000000..8df630e
--- /dev/null
+++ b/adapters/common/utils/grpc_utils.py
@@ -0,0 +1,109 @@
+#
+# 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.
+#
+
+"""
+Utilities to handle gRPC server and client side code in a Twisted environment
+"""
+import structlog
+from concurrent.futures import Future
+from twisted.internet import reactor
+from twisted.internet.defer import Deferred
+from twisted.python.threadable import isInIOThread
+
+
+log = structlog.get_logger()
+
+
+def twisted_async(func):
+ """
+ This decorator can be used to implement a gRPC method on the twisted
+ thread, allowing asynchronous programming in Twisted while serving
+ a gRPC call.
+
+ gRPC methods normally are called on the futures.ThreadPool threads,
+ so these methods cannot directly use Twisted protocol constructs.
+ If the implementation of the methods needs to touch Twisted, it is
+ safer (or mandatory) to wrap the method with this decorator, which will
+ call the inner method from the external thread and ensure that the
+ result is passed back to the foreign thread.
+
+ Example usage:
+
+ When implementing a gRPC server, typical pattern is:
+
+ class SpamService(SpamServicer):
+
+ def GetBadSpam(self, request, context):
+ '''this is called from a ThreadPoolExecutor thread'''
+ # generally unsafe to make Twisted calls
+
+ @twisted_async
+ def GetSpamSafely(self, request, context):
+ '''this method now is executed on the Twisted main thread
+ # safe to call any Twisted protocol functions
+
+ @twisted_async
+ @inlineCallbacks
+ def GetAsyncSpam(self, request, context):
+ '''this generator can use inlineCallbacks Twisted style'''
+ result = yield some_async_twisted_call(request)
+ returnValue(result)
+
+ """
+ def in_thread_wrapper(*args, **kw):
+
+ if isInIOThread():
+
+ return func(*args, **kw)
+
+ f = Future()
+
+ def twisted_wrapper():
+ try:
+ d = func(*args, **kw)
+ if isinstance(d, Deferred):
+
+ def _done(result):
+ f.set_result(result)
+ f.done()
+
+ def _error(e):
+ f.set_exception(e)
+ f.done()
+
+ d.addCallback(_done)
+ d.addErrback(_error)
+
+ else:
+ f.set_result(d)
+ f.done()
+
+ except Exception, e:
+ f.set_exception(e)
+ f.done()
+
+ reactor.callFromThread(twisted_wrapper)
+ try:
+ result = f.result()
+ except Exception, e:
+ log.exception(e=e, func=func, args=args, kw=kw)
+ raise
+
+ return result
+
+ return in_thread_wrapper
+
+