Wangle Echo Server & Client

Author: claudiouzelac

examples/wangle/echo/BUILD

@@ -0,0 +1,25 @@
+licenses(["notice"])
+
+cc_binary(
+  name = "echo_server",
+  visibility = ["//visibility:public"],
+  srcs = ["EchoServer.cpp"],
+  deps = [
+    "//third_party/wangle:wangle",
+    "//third_party/folly:folly",
+    "//third_party/glog:glog"
+  ]
+)
+
+cc_binary(
+  name = "echo_client",
+  visibility = ["//visibility:public"],
+  srcs = ["EchoClient.cpp"],
+  deps = [
+    "//third_party/wangle:wangle",
+    "//third_party/folly:folly",
+    "//third_party/glog:glog"
+  ]
+)
+
+

examples/wangle/echo/EchoClient.cpp

@@ -0,0 +1,77 @@
+#include <gflags/gflags.h>
+#include <iostream>
+#include <wangle/bootstrap/ClientBootstrap.h>
+#include <wangle/channel/AsyncSocketHandler.h>
+#include <wangle/channel/EventBaseHandler.h>
+#include <wangle/codec/LineBasedFrameDecoder.h>
+#include <wangle/codec/StringCodec.h>
+
+using namespace folly;
+using namespace wangle;
+
+DEFINE_int32(port, 8080, "echo server port");
+DEFINE_string(host, "::1", "echo server address");
+
+typedef Pipeline<folly::IOBufQueue&, std::string> EchoPipeline;
+
+// the handler for receiving messages back from the server
+class EchoHandler : public HandlerAdapter<std::string> {
+ public:
+  virtual void read(Context* ctx, std::string msg) override {
+    std::cout << "received back: " << msg;
+  }
+  virtual void readException(Context* ctx, exception_wrapper e) override {
+    std::cout << exceptionStr(e) << std::endl;
+    close(ctx);
+  }
+  virtual void readEOF(Context* ctx) override {
+    std::cout << "EOF received :(" << std::endl;
+    close(ctx);
+  }
+};
+
+// chains the handlers together to define the response pipeline
+class EchoPipelineFactory : public PipelineFactory<EchoPipeline> {
+ public:
+  EchoPipeline::Ptr newPipeline(std::shared_ptr<AsyncTransportWrapper> sock) {
+    auto pipeline = EchoPipeline::create();
+    pipeline->addBack(AsyncSocketHandler(sock));
+    pipeline->addBack(
+        EventBaseHandler()); // ensure we can write from any thread
+    pipeline->addBack(LineBasedFrameDecoder(8192, false));
+    pipeline->addBack(StringCodec());
+    pipeline->addBack(EchoHandler());
+    pipeline->finalize();
+    return pipeline;
+  }
+};
+
+int main(int argc, char** argv) {
+  gflags::ParseCommandLineFlags(&argc, &argv, true);
+
+  ClientBootstrap<EchoPipeline> client;
+  client.group(std::make_shared<wangle::IOThreadPoolExecutor>(1));
+  client.pipelineFactory(std::make_shared<EchoPipelineFactory>());
+  auto pipeline = client.connect(SocketAddress(FLAGS_host, FLAGS_port)).get();
+
+  try {
+    while (true) {
+      std::string line;
+      std::getline(std::cin, line);
+      if (line == "") {
+        break;
+      }
+
+      pipeline->write(line + "\r\n").get();
+      if (line == "bye") {
+        pipeline->close();
+        break;
+      }
+    }
+  } catch (const std::exception& e) {
+    std::cout << exceptionStr(e) << std::endl;
+  }
+
+  return 0;
+}
+

examples/wangle/echo/EchoServer.cpp

@@ -0,0 +1,48 @@
+#include <gflags/gflags.h>
+#include <wangle/bootstrap/ServerBootstrap.h>
+#include <wangle/channel/AsyncSocketHandler.h>
+#include <wangle/codec/LineBasedFrameDecoder.h>
+#include <wangle/codec/StringCodec.h>
+
+using namespace folly;
+using namespace wangle;
+
+DEFINE_int32(port, 8080, "echo server port");
+
+typedef Pipeline<IOBufQueue&, std::string> EchoPipeline;
+
+// the main logic of our echo server; receives a string and writes it straight
+// back
+class EchoHandler : public HandlerAdapter<std::string> {
+ public:
+  virtual void read(Context* ctx, std::string msg) override {
+    std::cout << "handling " << msg << std::endl;
+    write(ctx, msg + "\r\n");
+  }
+};
+
+// where we define the chain of handlers for each messeage received
+class EchoPipelineFactory : public PipelineFactory<EchoPipeline> {
+ public:
+  EchoPipeline::Ptr newPipeline(std::shared_ptr<AsyncTransportWrapper> sock) {
+    auto pipeline = EchoPipeline::create();
+    pipeline->addBack(AsyncSocketHandler(sock));
+    pipeline->addBack(LineBasedFrameDecoder(8192));
+    pipeline->addBack(StringCodec());
+    pipeline->addBack(EchoHandler());
+    pipeline->finalize();
+    return pipeline;
+  }
+};
+
+int main(int argc, char** argv) {
+  gflags::ParseCommandLineFlags(&argc, &argv, true);
+
+  ServerBootstrap<EchoPipeline> server;
+  server.childPipeline(std::make_shared<EchoPipelineFactory>());
+  server.bind(FLAGS_port);
+  server.waitForStop();
+
+  return 0;
+}
+

examples/wangle/echo/README.md

@@ -0,0 +1,13 @@
+# Wangle Examples
+
+This directory provides examples of using the Wangle Echo Server.
+
+## Compiling
+
+  Echo Server:
+
+  `bazel build //examples/wangle/echo:echo_server`
+
+  Echo Client:
+
+  `bazel build //examples/wangle/echo:echo_client`

third_party/wangle/BUILD

@@ -84,6 +84,23 @@ cc_library(
   ]
 )
 
+cc_library(
+  name = "codec",
+  visibility = ["//visibility:public"],
+  includes = [
+    "upstream",
+  ],
+  hdrs = glob(["upstream/wangle/codec/*.h"]),
+  srcs = [
+    "upstream/wangle/codec/LineBasedFrameDecoder.cpp",
+    "upstream/wangle/codec/LengthFieldPrepender.cpp",
+    "upstream/wangle/codec/LengthFieldBasedFrameDecoder.cpp"
+  ],
+  deps = [
+    ":channel"
+  ]
+)
+
 # Disabled because dependings on boost/thread
 #
 # cc_test(
@@ -119,5 +136,6 @@ cc_library(
     ":channel",
     ":concurrent",
     ":ssl",
+    ":codec"
   ]
 )