grpc over http/2 poc

buildSrc/src/main/groovy/com.flipkart.varadhi.java-common-conventions.gradle

@@ -18,6 +18,8 @@ ext {
     slf4j_version = "2.0.7"
     javax_version = "1.3.2"
     vertx_version = "4.4.4"
+    protoc_version = "3.23.2"
+    grpc_version = "1.56.0"
 
     otl_version = "1.25.0"
     micrometer_version = "1.10.6"

server/build.gradle

@@ -1,9 +1,36 @@
 import org.gradle.nativeplatform.platform.internal.DefaultNativePlatform
 
+buildscript {
+    dependencies {
+        // ASSUMES GRADLE 2.12 OR HIGHER. Use plugin version 0.7.5 with earlier gradle versions
+        classpath 'com.google.protobuf:protobuf-gradle-plugin:0.9.3'
+    }
+}
+
 plugins {
     id 'com.flipkart.varadhi.java-application-conventions'
+    id 'com.google.protobuf' version "0.9.3"
 }
 
+protobuf {
+    protoc {
+        artifact = "com.google.protobuf:protoc:$protoc_version"
+    }
+    plugins {
+        grpc {
+            artifact = "io.grpc:protoc-gen-grpc-java:$grpc_version"
+        }
+        vertx {
+            artifact = "io.vertx:vertx-grpc-protoc-plugin2:$vertx_version"
+        }
+    }
+    generateProtoTasks {
+        all()*.plugins {
+            grpc
+            vertx
+        }
+    }
+}
 
 dependencies {
 
@@ -22,6 +49,9 @@ dependencies {
     implementation("io.vertx:vertx-config")
     implementation("io.vertx:vertx-config-yaml")
     implementation("io.vertx:vertx-web")
+    implementation("io.vertx:vertx-grpc-server:$vertx_version")
+    implementation("io.vertx:vertx-grpc-client:$vertx_version")
+    implementation("io.vertx:vertx-grpc-context-storage:$vertx_version")
     implementation("io.vertx:vertx-auth-common")
     implementation("io.vertx:vertx-auth-jwt")
     implementation("io.vertx:vertx-opentelemetry")

server/src/main/java/com/flipkart/varadhi/RestVerticle.java

@@ -1,18 +1,26 @@
 package com.flipkart.varadhi;
 
 import com.flipkart.varadhi.exceptions.InvalidStateException;
+import com.flipkart.varadhi.web.Extensions;
 import com.flipkart.varadhi.web.FailureHandler;
 import com.flipkart.varadhi.web.routes.RouteBehaviour;
 import com.flipkart.varadhi.web.routes.RouteConfigurator;
 import com.flipkart.varadhi.web.routes.RouteDefinition;
+import com.flipkart.varadhi.web.v1.proto.MessageProducerGrpc;
+import com.flipkart.varadhi.web.v1.proto.SingleMessageResponse;
 import io.vertx.core.AbstractVerticle;
 import io.vertx.core.Promise;
+import io.vertx.core.http.HttpMethod;
 import io.vertx.core.http.HttpServer;
 import io.vertx.core.http.HttpServerOptions;
+import io.vertx.core.http.HttpVersion;
 import io.vertx.ext.web.Route;
 import io.vertx.ext.web.Router;
+import io.vertx.grpc.common.GrpcStatus;
+import io.vertx.grpc.server.GrpcServer;
 import lombok.extern.slf4j.Slf4j;
 
+import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 
@@ -36,6 +44,27 @@ public void start(Promise<Void> startPromise) {
         log.info("HttpServer Starting.");
         Router router = Router.router(vertx);
 
+        // grpc
+        GrpcServer grpcServer = GrpcServer.server(vertx);
+
+        grpcServer.callHandler(MessageProducerGrpc.getProduceMethod(), request -> {
+            request.response().status(GrpcStatus.OK).statusMessage("OK")
+                    .end(SingleMessageResponse.newBuilder().setOffset("0001").build());
+        });
+
+        router.route()
+                .consumes("application/grpc")
+                .produces("application/grpc")
+                .handler(req -> grpcServer.handle(req.request()));
+
+        router.route()
+                .consumes("application/json")
+                .produces("application/json")
+                .path("/topics/produce")
+                .method(HttpMethod.POST)
+                .handler(rc -> Extensions.RoutingContextExtension.endRequestWithResponse(rc, 200, "0001"));
+
+        // http
         FailureHandler failureHandler = new FailureHandler();
         for (RouteDefinition def : apiRoutes) {
             Route route = router.route().method(def.method()).path(def.path());

server/src/main/java/com/flipkart/varadhi/web/v1/TopicHandlers.java

@@ -9,6 +9,7 @@
 import com.flipkart.varadhi.services.VaradhiTopicService;
 import com.flipkart.varadhi.web.Extensions.RequestBodyExtension;
 import com.flipkart.varadhi.web.Extensions.RoutingContextExtension;
+import com.flipkart.varadhi.web.HandlerUtil;
 import com.flipkart.varadhi.web.routes.RouteDefinition;
 import com.flipkart.varadhi.web.routes.RouteProvider;
 import com.flipkart.varadhi.web.routes.SubRoutes;

server/src/main/proto/api.v1.proto

@@ -0,0 +1,19 @@
+syntax = "proto3";
+
+option java_multiple_files = true;
+option java_package = "com.flipkart.varadhi.web.v1.proto";
+option java_outer_classname = "ProduceApi";
+
+// The greeting service definition.
+service MessageProducer {
+    // Sends a greeting
+    rpc produce (SingleMessageRequest) returns (SingleMessageResponse) {}
+}
+
+message SingleMessageRequest {
+    string payload = 1;
+}
+
+message SingleMessageResponse {
+    string offset = 1;
+}