Fix to use the correct gRPC method type when creating a method descriptor

Author: thegridman

nima/grpc/webserver/src/main/java/io/helidon/nima/grpc/webserver/Grpc.java

@@ -125,7 +125,7 @@ private static <ResT, ReqT> Grpc<ReqT, ResT> grpc(Descriptors.FileDescriptor pro
 
         io.grpc.MethodDescriptor.Builder<ReqT, ResT> grpcDesc = io.grpc.MethodDescriptor.<ReqT, ResT>newBuilder()
                 .setFullMethodName(io.grpc.MethodDescriptor.generateFullMethodName(serviceName, methodName))
-                .setType(io.grpc.MethodDescriptor.MethodType.UNARY).setFullMethodName(path).setRequestMarshaller(reqMarshaller)
+                .setType(getMethodType(mtd)).setFullMethodName(path).setRequestMarshaller(reqMarshaller)
                 .setResponseMarshaller(resMarshaller).setSampledToLocalTracing(true);
 
         return new Grpc<>(grpcDesc.build(), PathMatchers.exact(path), requestType, responsetype, callHandler);
@@ -178,4 +178,19 @@ private static String getOuterClassFromFileName(String name) {
 
         return sb.toString();
     }
+
+    private static io.grpc.MethodDescriptor.MethodType getMethodType(Descriptors.MethodDescriptor mtd) {
+        if (mtd.isClientStreaming()) {
+            if (mtd.isServerStreaming()) {
+                return MethodDescriptor.MethodType.BIDI_STREAMING;
+            }
+            else {
+                return MethodDescriptor.MethodType.CLIENT_STREAMING;
+            }
+        }
+        else if (mtd.isServerStreaming()) {
+            return MethodDescriptor.MethodType.SERVER_STREAMING;
+        }
+        return MethodDescriptor.MethodType.UNARY;
+    }
 }