session: api to emulate network conditions

atom/browser/api/atom_api_session.cc

@@ -19,6 +19,8 @@
 #include "base/prefs/pref_service.h"
 #include "base/strings/string_util.h"
 #include "base/thread_task_runner_handle.h"
+#include "brightray/browser/net/devtools_network_conditions.h"
+#include "brightray/browser/net/devtools_network_controller.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/storage_partition.h"
@@ -294,6 +296,43 @@ void Session::SetDownloadPath(const base::FilePath& path) {
       prefs::kDownloadDefaultDirectory, path);
 }
 
+void Session::EnableNetworkEmulation(const mate::Dictionary& options) {
+  scoped_ptr<brightray::DevToolsNetworkConditions> conditions;
+  bool offline = false;
+  double latency, download_throughput, upload_throughput;
+  if (options.Get("offline", &offline) && offline) {
+    conditions.reset(new brightray::DevToolsNetworkConditions(offline));
+  } else {
+    options.Get("latency", &latency);
+    options.Get("downloadThroughput", &download_throughput);
+    options.Get("uploadThroughput", &upload_throughput);
+    conditions.reset(
+        new brightray::DevToolsNetworkConditions(false,
+                                                 latency,
+                                                 download_throughput,
+                                                 upload_throughput));
+  }
+  auto controller = browser_context_->GetDevToolsNetworkController();
+
+  BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
+      base::Bind(&brightray::DevToolsNetworkController::SetNetworkState,
+                 base::Unretained(controller),
+                 std::string(),
+                 base::Passed(&conditions)));
+}
+
+void Session::DisableNetworkEmulation() {
+  scoped_ptr<brightray::DevToolsNetworkConditions> conditions(
+      new brightray::DevToolsNetworkConditions(false));
+  auto controller = browser_context_->GetDevToolsNetworkController();
+
+  BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
+      base::Bind(&brightray::DevToolsNetworkController::SetNetworkState,
+                 base::Unretained(controller),
+                 std::string(),
+                 base::Passed(&conditions)));
+}
+
 v8::Local<v8::Value> Session::Cookies(v8::Isolate* isolate) {
   if (cookies_.IsEmpty()) {
     auto handle = atom::api::Cookies::Create(isolate, browser_context());
@@ -310,6 +349,8 @@ mate::ObjectTemplateBuilder Session::GetObjectTemplateBuilder(
       .SetMethod("clearStorageData", &Session::ClearStorageData)
       .SetMethod("setProxy", &Session::SetProxy)
       .SetMethod("setDownloadPath", &Session::SetDownloadPath)
+      .SetMethod("enableNetworkEmulation", &Session::EnableNetworkEmulation)
+      .SetMethod("disableNetworkEmulation", &Session::DisableNetworkEmulation)
       .SetProperty("cookies", &Session::Cookies);
 }
 

atom/browser/api/atom_api_session.h

@@ -20,6 +20,7 @@ class FilePath;
 
 namespace mate {
 class Arguments;
+class Dictionary;
 }
 
 namespace atom {
@@ -65,6 +66,8 @@ class Session: public mate::TrackableObject<Session>,
   void ClearStorageData(mate::Arguments* args);
   void SetProxy(const std::string& proxy, const base::Closure& callback);
   void SetDownloadPath(const base::FilePath& path);
+  void EnableNetworkEmulation(const mate::Dictionary& options);
+  void DisableNetworkEmulation();
   v8::Local<v8::Value> Cookies(v8::Isolate* isolate);
 
   // Cached object for cookies API.

docs/api/session.md

@@ -191,3 +191,18 @@ proxy-uri = [<proxy-scheme>"://"]<proxy-host>[":"<proxy-port>]
 
 Sets download saving directory. By default, the download directory will be the
 `Downloads` under the respective app folder.
+
+### `session.enableNetworkEmulation(options)`
+
+* `options` Object
+  * `offline` Boolean - Whether to emulate network outage.
+  * `latency` Double - RTT in ms
+  * `downloadThroughput` Double - Download rate in Bps
+  * `uploadThroughput` Double - Upload rate in Bps
+
+Emulates network with the given configuration for the `session`.
+
+### `session.disableNetworkEmulation`
+
+Disables any network emulation already active for the `session`. Resets to
+the original network configuration.