Add an example to test server concurrency.

examples/concurrency_test.cc

@@ -0,0 +1,53 @@
+#include <iostream>
+#include <string>
+#include <thread>
+#include <vector>
+
+#include "webcc/client_session.h"
+#include "webcc/logger.h"
+
+int main(int argc, const char* argv[]) {
+  if (argc < 3) {
+    std::cerr << "Usage: concurrency_test <workers> <url>" << std::endl;
+    std::cerr << "E.g.," << std::endl;
+    std::cerr << "  $ concurrency_test 10 https://api.github.com/public/events"
+              << std::endl;
+    std::cerr << "  $ concurrency_test 10 http://localhost:8080/" << std::endl;
+    return 1;
+  }
+
+  WEBCC_LOG_INIT("", webcc::LOG_CONSOLE);
+
+  int workers = std::atoi(argv[1]);
+  std::string url = argv[2];
+
+  LOG_USER("Workers: %d", workers);
+  LOG_USER("URL: %s", url.c_str());
+
+  std::vector<std::thread> threads;
+
+  for (int i = 0; i < workers; ++i) {
+    threads.emplace_back([&url]() {
+      // NOTE: Each thread has its own client session.
+      webcc::ClientSession session;
+      session.set_timeout(180);
+
+      try {
+        LOG_USER("Start");
+
+        session.Send(webcc::RequestBuilder{}.Get(url)());
+
+        LOG_USER("End");
+
+      } catch (const webcc::Error& error) {
+        LOG_ERRO("Error: %s", error.message().c_str());
+      }
+    });
+  }
+
+  for (int i = 0; i < workers; ++i) {
+    threads[i].join();
+  }
+
+  return 0;
+}