closes #205

 Bidirectional service test copied from
https://github.com/grpc/grpc-java/blob/42d7fba1b86ad711687944dc91d0ea8ab4908f44/examples/src/test/java/io/grpc/examples/routeguide/RouteGuideServerTest.java#L211

Author: Alexander Furer

grpc-spring-boot-starter-demo/src/main/java/org/lognet/springboot/grpc/demo/routeguide/RouteGuideService.java

@@ -0,0 +1,67 @@
+package org.lognet.springboot.grpc.demo.routeguide;
+
+import io.grpc.examples.routeguide.Point;
+import io.grpc.examples.routeguide.RouteGuideGrpc;
+import io.grpc.examples.routeguide.RouteNote;
+import io.grpc.stub.StreamObserver;
+import lombok.extern.slf4j.Slf4j;
+import org.lognet.springboot.grpc.GRpcService;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
+@Slf4j
+@GRpcService
+public class RouteGuideService  extends RouteGuideGrpc.RouteGuideImplBase{
+
+    private final ConcurrentMap<Point, List<RouteNote>> routeNotes = new ConcurrentHashMap<>();
+    /**
+     * Receives a stream of message/location pairs, and responds with a stream of all previous
+     * messages at each of those locations.
+     *
+     * @param responseObserver an observer to receive the stream of previous messages.
+     * @return an observer to handle requested message/location pairs.
+     */
+    @Override
+    public StreamObserver<RouteNote> routeChat(final StreamObserver<RouteNote> responseObserver) {
+        return new StreamObserver<RouteNote>() {
+            @Override
+            public void onNext(RouteNote note) {
+                List<RouteNote> notes = getOrCreateNotes(note.getLocation());
+
+                // Respond with all previous notes at this location.
+                for (RouteNote prevNote : notes.toArray(new RouteNote[0])) {
+                    responseObserver.onNext(prevNote);
+                }
+
+                // Now add the new note to the list
+                notes.add(note);
+            }
+
+            @Override
+            public void onError(Throwable t) {
+                log.warn( "routeChat cancelled");
+            }
+
+            @Override
+            public void onCompleted() {
+                responseObserver.onCompleted();
+            }
+        };
+    }
+
+    /**
+     * Get the notes list for the given location. If missing, create it.
+     */
+    private List<RouteNote> getOrCreateNotes(Point location) {
+        List<RouteNote> notes = Collections.synchronizedList(new ArrayList<RouteNote>());
+        List<RouteNote> prevNotes = routeNotes.putIfAbsent(location, notes);
+        return prevNotes != null ? prevNotes : notes;
+    }
+
+
+
+}

grpc-spring-boot-starter-demo/src/main/proto/route_guide.proto

@@ -0,0 +1,51 @@
+// Copyright 2015 The gRPC 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.
+syntax = "proto3";
+
+option java_multiple_files = true;
+option java_package = "io.grpc.examples.routeguide";
+option java_outer_classname = "RouteGuideProto";
+option objc_class_prefix = "RTG";
+
+package routeguide;
+
+// Interface exported by the server.
+service RouteGuide {
+
+
+    // A Bidirectional streaming RPC.
+    //
+    // Accepts a stream of RouteNotes sent while a route is being traversed,
+    // while receiving other RouteNotes (e.g. from other users).
+    rpc RouteChat(stream RouteNote) returns (stream RouteNote) {}
+}
+
+// Points are represented as latitude-longitude pairs in the E7 representation
+// (degrees multiplied by 10**7 and rounded to the nearest integer).
+// Latitudes should be in the range +/- 90 degrees and longitude should be in
+// the range +/- 180 degrees (inclusive).
+message Point {
+    int32 latitude = 1;
+    int32 longitude = 2;
+}
+
+
+// A RouteNote is a message sent while at a given point.
+message RouteNote {
+    // The location from which the message is sent.
+    Point location = 1;
+
+    // The message to be sent.
+    string message = 2;
+}