GAIA

 // Copyright 2018, Beeri 15.  All rights reserved.
 // Author: Roman Gershman (romange@gmail.com)
 //
 #include "util/http/status_page.h"
 
 #include "absl/strings/str_replace.h"
 #include "base/walltime.h"
 #include "util/proc_stats.h"
 #include "util/stats/varz_stats.h"
 
 namespace util {
 namespace http {
 using namespace std;
 using namespace boost;
 using beast::http::field;
 namespace h2 = beast::http;
 typedef h2::response<h2::string_body> StringResponse;
 
 namespace {
 
 string GetTimerString(uint64 seconds) {
   char buf[128];
   uint32 hours = seconds / 3600;
   seconds = seconds % 3600;
   uint32 mins = seconds / 60;
   uint32 secs = seconds % 60;
   snprintf(buf, sizeof buf, "%" PRIu32 ":%" PRIu32 ":%" PRIu32, hours, mins, secs);
   return buf;
 }
 
 string StatusLine(const string& name, const string& val) {
   string res("<div>");
   res.append(name).append(":<span class='key_text'>").append(val).append("</span></div>\n");
   return res;
 }
 }  // namespace
 
 StringResponse BuildStatusPage(const QueryArgs& args, const char* resource_prefix) {
   StringResponse response(h2::status::ok, 11);
 
   bool output_json = false;
 
   string varz;
   auto start = base::GetMonotonicMicrosFast();
 
   VarzListNode::IterateValues([&varz](const string& nm, const string& val) {
     absl::StrAppend(&varz, "\"", nm, "\": ", val, ",\n");
   });
   absl::StrAppend(&varz, "\"current-time\": ", time(nullptr), ",\n");
   varz.resize(varz.size() - 2);
 
   for (const auto& k_v : args) {
     if (k_v.first == "o" && k_v.second == "json")
       output_json = true;
   }
 
   auto delta_ms = (base::GetMonotonicMicrosFast() - start) / 1000;
   if (output_json) {
     response.set(field::content_type, kJsonMime);
     response.body() = "{" + varz + "}\n";
     return response;
   }
 
   string a = "<!DOCTYPE html>\n<html><head>\n";
   a += R"(<meta http-equiv='Content-Type' content='text/html; charset=UTF-8'/>
     <link href='https://fonts.googleapis.com/css?family=Roboto:400,300' rel='stylesheet'
      type='text/css'>
     <link rel='stylesheet' href='{s3_path}/status_page.css'>
     <script type="text/javascript" src="{s3_path}/status_page.js"></script>
 </head>
 <body>
 <div><img src='{s3_path}/logo.png' width="160"/></div>)";
 
   a = absl::StrReplaceAll(a, {{"{s3_path}", resource_prefix}});
 
   a += "\n<div class='left_panel'></div>\n";
   a += "<div class='styled_border'>\n";
   a += StatusLine("Status", "OK");
 
   static std::atomic<time_t> start_time_cached{0};
   time_t start_time = start_time_cached.load(std::memory_order_relaxed);
   if (start_time == 0) {
     util::ProcessStats stats = util::ProcessStats::Read();
     start_time = stats.start_time_seconds;
     start_time_cached.store(stats.start_time_seconds, std::memory_order_seq_cst);
   }
   a += StatusLine("Started on", base::PrintLocalTime(start_time));
   a += StatusLine("Uptime", GetTimerString(time(NULL) - start_time));
   a += StatusLine("Render Latency", absl::StrCat(delta_ms, " ms"));
 
   a += R"(</div>
 </body>
 <script>
 var json_text1 = {)";
   a += varz + R"(};
 document.querySelector('.left_panel').innerHTML = JsonToHTML(json_text1);
 </script>
 </html>)";
 
   response.set(field::content_type, kHtmlMime);
   response.body() = std::move(a);
   return response;
 }
 
 }  // namespace http
 }  // namespace util