Telemetry / Devtools TraceHandler: exposes tracing via dev tools.

content/browser/debugger/devtools_browser_target.cc

Index: content/browser/debugger/devtools_browser_target.cc
diff --git a/content/browser/debugger/devtools_browser_target.cc b/content/browser/debugger/devtools_browser_target.cc
new file mode 100644
index 0000000000000000000000000000000000000000..95d57a9e79f99cba5694e7fc137261e879432236
--- /dev/null
+++ b/content/browser/debugger/devtools_browser_target.cc
@@ -0,0 +1,118 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/debugger/devtools_browser_target.h"
+
+#include "base/json/json_reader.h"
+#include "base/json/json_writer.h"
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/values.h"
+
+
+namespace content {
+
+DevToolsBrowserTarget::DevToolsBrowserTarget(int connection_id)
+    : connection_id_(connection_id) {
+}
+
+DevToolsBrowserTarget::~DevToolsBrowserTarget() {
+  for (HandlersMap::iterator i = handlers_.begin(); i != handlers_.end(); ++i)
+    delete i->second;
+}
+
+void DevToolsBrowserTarget::RegisterHandler(Handler* handler) {
+  std::string domain = handler->Domain();
+  DCHECK(handlers_.find(domain) == handlers_.end());
+  handlers_[domain] = handler;
+}
+
+std::string DevToolsBrowserTarget::HandleMessage(const std::string& data) {
+  int error_code;
+  std::string error_message;
+  scoped_ptr<base::Value> command(
+      base::JSONReader::ReadAndReturnError(
+          data, 0, &error_code, &error_message));
+
+  if (!command || !command->IsType(base::Value::TYPE_DICTIONARY))
+    return SerializeErrorResponse(
+        -1, CreateErrorObject(error_code, error_message));
+
+  int request_id;
+  std::string domain;
+  std::string method;
+  base::DictionaryValue* command_dict = NULL;
+  bool ok = true;
+  ok &= command->GetAsDictionary(&command_dict);
+  ok &= command_dict->GetInteger("id", &request_id);
+  ok &= command_dict->GetString("method", &method);
+  if (!ok)
+    return SerializeErrorResponse(
+        request_id, CreateErrorObject(-1, "Malformed request"));
+
+  base::DictionaryValue* params = NULL;
+  command_dict->GetDictionary("params", &params);
+
+  size_t pos = method.find(".");
+  if (pos == std::string::npos)
+    return SerializeErrorResponse(
+        request_id, CreateErrorObject(-1, "Method unsupported"));
+
+  domain = method.substr(0, pos);
+  if (domain.empty() || handlers_.find(domain) == handlers_.end())
+    return SerializeErrorResponse(
+        request_id, CreateErrorObject(-1, "Domain unsupported"));
+
+  base::Value* error_object = NULL;
+  base::Value* domain_result = handlers_[domain]->OnProtocolCommand(
+      method, params, &error_object);
+
+  if (error_object)
+    return SerializeErrorResponse(request_id, error_object);
+
+  if (!domain_result)
+    return SerializeErrorResponse(
+        request_id, CreateErrorObject(-1, "Invalid call"));
+
+  DictionaryValue* response = new DictionaryValue();
+  response->Set("result", domain_result);
+  return SerializeResponse(request_id, response);
+}
+
+std::string DevToolsBrowserTarget::SerializeErrorResponse(
+    int request_id, base::Value* error_object) {
+  scoped_ptr<base::DictionaryValue> error_response(new base::DictionaryValue());
+  error_response->SetInteger("id", request_id);
+  error_response->Set("error", error_object);
+  // Serialize response.
+  std::string json_response;
+  base::JSONWriter::WriteWithOptions(error_response.get(),
+                                     base::JSONWriter::OPTIONS_PRETTY_PRINT,
+                                     &json_response);
+  return json_response;
+}
+
+base::Value* DevToolsBrowserTarget::CreateErrorObject(
+    int error_code, const std::string& message) {
+  base::DictionaryValue* error_object = new base::DictionaryValue();
+  error_object->SetInteger("code", error_code);
+  error_object->SetString("message", message);
+  return error_object;
+}
+
+std::string DevToolsBrowserTarget::SerializeResponse(
+    int request_id, base::Value* response) {
+  scoped_ptr<base::DictionaryValue> ret(new base::DictionaryValue());
+  ret->SetInteger("id", request_id);
+  ret->Set("response", response);
+
+  // Serialize response.
+  std::string json_response;
+  base::JSONWriter::WriteWithOptions(ret.get(),
+                                     base::JSONWriter::OPTIONS_PRETTY_PRINT,
+                                     &json_response);
+  return json_response;
+}
+
+}  // namespace content