grpc: add health checks to python services (#28)

also converted line endings for recommendationservice/requirements.txt from
dos to unix.

src/recommendationservice/Dockerfile

@@ -3,6 +3,11 @@ FROM grpc/python:1.0
 # show python logs as they occur
 ENV PYTHONUNBUFFERED=0
 
+# download the grpc health probe
+RUN GRPC_HEALTH_PROBE_VERSION=v0.1.0-alpha.1 && \
+    wget -qO/bin/grpc_health_probe https://github.com/grpc-ecosystem/grpc-health-probe/releases/download/${GRPC_HEALTH_PROBE_VERSION}/grpc_health_probe-linux-amd64 && \
+    chmod +x /bin/grpc_health_probe
+
 # get packages
 WORKDIR /recommendationservice
 COPY requirements.txt requirements.txt

src/recommendationservice/demo_pb2_grpc.py

@@ -1,19 +1,3 @@
-#!/usr/bin/python
-#
-# Copyright 2018 Google LLC
-#
-# 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.
-
 # Generated by the gRPC Python protocol compiler plugin. DO NOT EDIT!
 import grpc
 
@@ -441,11 +425,6 @@ class CheckoutServiceStub(object):
     Args:
       channel: A grpc.Channel.
     """
-    self.CreateOrder = channel.unary_unary(
-        '/hipstershop.CheckoutService/CreateOrder',
-        request_serializer=demo__pb2.CreateOrderRequest.SerializeToString,
-        response_deserializer=demo__pb2.CreateOrderResponse.FromString,
-        )
     self.PlaceOrder = channel.unary_unary(
         '/hipstershop.CheckoutService/PlaceOrder',
         request_serializer=demo__pb2.PlaceOrderRequest.SerializeToString,
@@ -458,13 +437,6 @@ class CheckoutServiceServicer(object):
 
   """
 
-  def CreateOrder(self, request, context):
-    # missing associated documentation comment in .proto file
-    pass
-    context.set_code(grpc.StatusCode.UNIMPLEMENTED)
-    context.set_details('Method not implemented!')
-    raise NotImplementedError('Method not implemented!')
-
   def PlaceOrder(self, request, context):
     # missing associated documentation comment in .proto file
     pass
@@ -475,11 +447,6 @@ class CheckoutServiceServicer(object):
 
 def add_CheckoutServiceServicer_to_server(servicer, server):
   rpc_method_handlers = {
-      'CreateOrder': grpc.unary_unary_rpc_method_handler(
-          servicer.CreateOrder,
-          request_deserializer=demo__pb2.CreateOrderRequest.FromString,
-          response_serializer=demo__pb2.CreateOrderResponse.SerializeToString,
-      ),
       'PlaceOrder': grpc.unary_unary_rpc_method_handler(
           servicer.PlaceOrder,
           request_deserializer=demo__pb2.PlaceOrderRequest.FromString,
@@ -489,3 +456,47 @@ def add_CheckoutServiceServicer_to_server(servicer, server):
   generic_handler = grpc.method_handlers_generic_handler(
       'hipstershop.CheckoutService', rpc_method_handlers)
   server.add_generic_rpc_handlers((generic_handler,))
+
+
+class AdsServiceStub(object):
+  """------------Ads service------------------
+
+  """
+
+  def __init__(self, channel):
+    """Constructor.
+
+    Args:
+      channel: A grpc.Channel.
+    """
+    self.GetAds = channel.unary_unary(
+        '/hipstershop.AdsService/GetAds',
+        request_serializer=demo__pb2.AdsRequest.SerializeToString,
+        response_deserializer=demo__pb2.AdsResponse.FromString,
+        )
+
+
+class AdsServiceServicer(object):
+  """------------Ads service------------------
+
+  """
+
+  def GetAds(self, request, context):
+    # missing associated documentation comment in .proto file
+    pass
+    context.set_code(grpc.StatusCode.UNIMPLEMENTED)
+    context.set_details('Method not implemented!')
+    raise NotImplementedError('Method not implemented!')
+
+
+def add_AdsServiceServicer_to_server(servicer, server):
+  rpc_method_handlers = {
+      'GetAds': grpc.unary_unary_rpc_method_handler(
+          servicer.GetAds,
+          request_deserializer=demo__pb2.AdsRequest.FromString,
+          response_serializer=demo__pb2.AdsResponse.SerializeToString,
+      ),
+  }
+  generic_handler = grpc.method_handlers_generic_handler(
+      'hipstershop.AdsService', rpc_method_handlers)
+  server.add_generic_rpc_handlers((generic_handler,))

src/recommendationservice/recommendation_server.py

@@ -15,16 +15,19 @@
 # limitations under the License.
 
 import grpc
-import demo_pb2
-import demo_pb2_grpc
 from concurrent import futures
 import time
 import traceback
 import random
 import os
-
 import googleclouddebugger
 
+import demo_pb2
+import demo_pb2_grpc
+from grpc_health.v1 import health_pb2
+from grpc_health.v1 import health_pb2_grpc
+
+
 # TODO(morganmclean,ahmetb) tracing currently disabled due to memory leak (see TODO below)
 # from opencensus.trace.ext.grpc import server_interceptor
 # from opencensus.trace.samplers import always_on
@@ -35,7 +38,7 @@ class RecommendationService(demo_pb2_grpc.RecommendationServiceServicer):
     def ListRecommendations(self, request, context):
         max_responses = 5
         # fetch list of products from product catalog stub
-        cat_response = stub.ListProducts(demo_pb2.Empty())
+        cat_response = product_catalog_stub.ListProducts(demo_pb2.Empty())
         product_ids = [x.id for x in cat_response.products]
         filtered_products = list(set(product_ids)-set(request.product_ids))
         num_products = len(filtered_products)
@@ -50,6 +53,11 @@ class RecommendationService(demo_pb2_grpc.RecommendationServiceServicer):
         response.product_ids.extend(prod_list)
         return response
 
+    def Check(self, request, context):
+        return health_pb2.HealthCheckResponse(
+            status=health_pb2.HealthCheckResponse.SERVING)
+
+
 if __name__ == "__main__":
     print("initializing recommendationservice")
 
@@ -78,16 +86,16 @@ if __name__ == "__main__":
     if catalog_addr == "":
         raise Exception('PRODUCT_CATALOG_SERVICE_ADDR environment variable not set')
     print("product catalog address: " + catalog_addr)
-
-    # stub for product catalog service
     channel = grpc.insecure_channel(catalog_addr)
-    stub = demo_pb2_grpc.ProductCatalogServiceStub(channel)
-    
+    product_catalog_stub = demo_pb2_grpc.ProductCatalogServiceStub(channel)
+
     # create gRPC server
     server = grpc.server(futures.ThreadPoolExecutor(max_workers=10)) # ,interceptors=(tracer_interceptor,))
 
     # add class to gRPC server
-    demo_pb2_grpc.add_RecommendationServiceServicer_to_server(RecommendationService(), server)
+    service = RecommendationService()
+    demo_pb2_grpc.add_RecommendationServiceServicer_to_server(service, server)
+    health_pb2_grpc.add_HealthServicer_to_server(service, server)
 
     # start server
     print("listening on port: " + port)

src/recommendationservice/requirements.txt

@@ -1,29 +1,30 @@
-cachetools==2.1.0
-certifi==2018.4.16
-chardet==3.0.4
-enum34==1.1.6
-futures==3.2.0
-google-api-core==1.2.1
-google-api-python-client==1.7.4
-google-auth==1.5.0
-google-auth-httplib2==0.0.3
-google-cloud-core==0.28.1
-google-cloud-trace==0.19.0
-google-python-cloud-debugger==2.8
-googleapis-common-protos==1.5.3
-grpcio==1.13.0
-grpcio-tools==1.0.0
-httplib2==0.11.3
-idna==2.7
-opencensus==0.1.5
-protobuf==3.5.2.post1
-pyasn1==0.4.3
-pyasn1-modules==0.2.2
-pytz==2018.5
-PyYAML==3.13
-requests==2.19.1
-rsa==3.4.2
-six==1.11.0
-uritemplate==3.0.0
-urllib3==1.23
-virtualenv==16.0.0
+cachetools==2.1.0
+certifi==2018.4.16
+chardet==3.0.4
+enum34==1.1.6
+futures==3.2.0
+google-api-core==1.2.1
+google-api-python-client==1.7.4
+google-auth==1.5.0
+google-auth-httplib2==0.0.3
+google-cloud-core==0.28.1
+google-cloud-trace==0.19.0
+google-python-cloud-debugger==2.8
+googleapis-common-protos==1.5.3
+grpcio==1.13.0
+grpcio-health-checking==1.14.1
+grpcio-tools==1.0.0
+httplib2==0.11.3
+idna==2.7
+opencensus==0.1.5
+protobuf==3.5.2.post1
+pyasn1==0.4.3
+pyasn1-modules==0.2.2
+pytz==2018.5
+PyYAML==3.13
+requests==2.19.1
+rsa==3.4.2
+six==1.11.0
+uritemplate==3.0.0
+urllib3==1.23
+virtualenv==16.0.0