components/safe_json_parser/safe_json_parser.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "components/safe_json_parser/safe_json_parser.h"
   6
   7 #include <string>
   8
   9 #include "base/strings/utf_string_conversions.h"
  10 #include "base/tuple.h"
  11 #include "base/values.h"
  12 #include "components/safe_json_parser/safe_json_parser_messages.h"
  13 #include "content/public/browser/browser_thread.h"
  14 #include "content/public/browser/utility_process_host.h"
  15 #include "grit/components_strings.h"
  16 #include "ipc/ipc_message_macros.h"
  17 #include "ui/base/l10n/l10n_util.h"
  18
  19 using content::BrowserThread;
  20 using content::UtilityProcessHost;
  21
  22 namespace safe_json_parser {
  23
  24 SafeJsonParser::SafeJsonParser(const std::string& unsafe_json,
  25                                const SuccessCallback& success_callback,
  26                                const ErrorCallback& error_callback)
  27     : unsafe_json_(unsafe_json),
  28       success_callback_(success_callback),
  29       error_callback_(error_callback) {
  30 }
  31
  32 void SafeJsonParser::Start() {
  33   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  34   BrowserThread::PostTask(
  35       BrowserThread::IO, FROM_HERE,
  36       base::Bind(&SafeJsonParser::StartWorkOnIOThread, this));
  37 }
  38
  39 SafeJsonParser::~SafeJsonParser() {
  40 }
  41
  42 void SafeJsonParser::StartWorkOnIOThread() {
  43   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  44   UtilityProcessHost* host =
  45       UtilityProcessHost::Create(this, base::MessageLoopProxy::current().get());
  46   host->SetName(
  47       l10n_util::GetStringUTF16(IDS_UTILITY_PROCESS_JSON_PARSER_NAME));
  48   host->Send(new SafeJsonParserMsg_ParseJSON(unsafe_json_));
  49 }
  50
  51 void SafeJsonParser::OnJSONParseSucceeded(const base::ListValue& wrapper) {
  52   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  53   const base::Value* value = NULL;
  54   CHECK(wrapper.Get(0, &value));
  55
  56   parsed_json_.reset(value->DeepCopy());
  57   ReportResults();
  58 }
  59
  60 void SafeJsonParser::OnJSONParseFailed(const std::string& error_message) {
  61   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  62   error_ = error_message;
  63   ReportResults();
  64 }
  65
  66 void SafeJsonParser::ReportResults() {
  67   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  68
  69   BrowserThread::PostTask(
  70       BrowserThread::UI, FROM_HERE,
  71       base::Bind(&SafeJsonParser::ReportResultOnUIThread, this));
  72 }
  73
  74 void SafeJsonParser::ReportResultOnUIThread() {
  75   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  76   if (error_.empty() && parsed_json_) {
  77     if (!success_callback_.is_null())
  78       success_callback_.Run(parsed_json_.Pass());
  79   } else {
  80     if (!error_callback_.is_null())
  81       error_callback_.Run(error_);
  82   }
  83 }
  84
  85 bool SafeJsonParser::OnMessageReceived(const IPC::Message& message) {
  86   bool handled = true;
  87   IPC_BEGIN_MESSAGE_MAP(SafeJsonParser, message)
  88     IPC_MESSAGE_HANDLER(SafeJsonParserHostMsg_ParseJSON_Succeeded,
  89                         OnJSONParseSucceeded)
  90     IPC_MESSAGE_HANDLER(SafeJsonParserHostMsg_ParseJSON_Failed,
  91                         OnJSONParseFailed)
  92     IPC_MESSAGE_UNHANDLED(handled = false)
  93   IPC_END_MESSAGE_MAP()
  94   return handled;
  95 }
  96
  97 }  // namespace safe_json_parser