gzip chrome://tracing resources.

content/browser/tracing/tracing_ui.cc

 // 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/tracing/tracing_ui.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <set>
@@ skipping 157 matching lines @@
   callback.Run(data_base64);
 }
 
 bool OnBeginJSONRequest(const std::string& path,
                         const WebUIDataSource::GotDataCallback& callback) {
   if (path == "json/categories") {
     return TracingController::GetInstance()->GetCategories(
         base::Bind(OnGotCategories, callback));
   }
 
   const char kBeginRecordingPath[] = "json/begin_recording?";

[sullivan, 2017/06/09 19:08:42]

What is this and how is it used? I see it called from here:
https://github.com/catapult-project/catapult/blob/master/tracing/tracing/ui/e...

But that file has some other paths that aren't handled here:
/json/begin_monitoring
/json/end_monitoring
/json/capture_monitoring_compressed
/json/get_monitoring_status

What's going on there?

[sullivan, 2017/06/09 21:22:29]

I ended up adding "json/begin_recording" to the gzip_excluded paths. I think
this should work, but I can't get that file to show up in the netstack when I
record traces.

   if (base::StartsWith(path, kBeginRecordingPath,
                        base::CompareCase::SENSITIVE)) {
     std::string data = path.substr(strlen(kBeginRecordingPath));
     return BeginRecording(data, callback);
   }
   if (path == "json/get_buffer_percent_full") {
     return TracingController::GetInstance()->GetTraceBufferUsage(
         base::Bind(OnTraceBufferUsageResult, callback));
   }
   if (path == "json/get_buffer_status") {
@@ skipping 44 matching lines @@
       base::Bind(&TracingUI::DoUpload, base::Unretained(this)));
   web_ui->RegisterMessageCallback(
       "doUploadBase64",
       base::Bind(&TracingUI::DoUploadBase64Encoded, base::Unretained(this)));
 
   // Set up the chrome://tracing/ source.
   BrowserContext* browser_context =
       web_ui->GetWebContents()->GetBrowserContext();
 
   WebUIDataSource* source = WebUIDataSource::Create(kChromeUITracingHost);
+  std::unordered_set<std::string> exclusions;
+  exclusions.insert("json/categories");
+  exclusions.insert("json/get_buffer_percent_full");
+  exclusions.insert("json/get_buffer_status");
+  exclusions.insert("json/end_recording_compressed");
+  source->UseGzip(exclusions);
   source->SetJsonPath("strings.js");
   source->SetDefaultResource(IDR_TRACING_HTML);
   source->AddResourcePath("tracing.js", IDR_TRACING_JS);
   source->SetRequestFilter(base::Bind(OnTracingRequest));
   WebUIDataSource::Add(browser_context, source);
   TracingControllerImpl::GetInstance()->RegisterTracingUI(this);
 }
 
 TracingUI::~TracingUI() {
   TracingControllerImpl::GetInstance()->UnregisterTracingUI(this);
@@ skipping 72 matching lines @@
     web_ui()->CallJavascriptFunctionUnsafe("onUploadComplete",
                                            base::Value(feedback));
   } else {
     web_ui()->CallJavascriptFunctionUnsafe("onUploadError",
                                            base::Value(feedback));
   }
   trace_uploader_.reset();
 }
 
 }  // namespace content