Line data    Source code

       1             : #include "source/server/admin/stats_html_render.h"
       2             : 
       3             : #include <algorithm>
       4             : 
       5             : #include "source/common/buffer/buffer_impl.h"
       6             : #include "source/common/common/assert.h"
       7             : #include "source/common/filesystem/filesystem_impl.h"
       8             : #include "source/common/html/utility.h"
       9             : #include "source/server/admin/admin_html_util.h"
      10             : 
      11             : #include "absl/strings/str_replace.h"
      12             : 
      13             : // Note: if you change this file, it's advisable to manually run
      14             : // test/integration/admin_html/web_test.sh to semi-automatically validate
      15             : // the web interface, in addition to updating and running unit tests.
      16             : //
      17             : // The admin web test does not yet run automatically.
      18             : 
      19             : namespace Envoy {
      20             : namespace Server {
      21             : 
      22             : StatsHtmlRender::StatsHtmlRender(Http::ResponseHeaderMap& response_headers,
      23             :                                  Buffer::Instance& response, const StatsParams& params)
      24             :     : StatsTextRender(params), active_(params.format_ == StatsFormat::ActiveHtml),
      25             :       json_histograms_(!active_ &&
      26           0 :                        params.histogram_buckets_mode_ == Utility::HistogramBucketsMode::Detailed) {
      27           0 :   AdminHtmlUtil::renderHead(response_headers, response);
      28           0 : }
      29             : 
      30           0 : void StatsHtmlRender::finalize(Buffer::Instance& response) {
      31           0 :   if (first_histogram_) {
      32           0 :     response.add("</pre>\n");
      33           0 :   }
      34             : 
      35           0 :   AdminHtmlUtil::finalize(response);
      36           0 : }
      37             : 
      38             : void StatsHtmlRender::setupStatsPage(const Admin::UrlHandler& url_handler,
      39           0 :                                      const StatsParams& params, Buffer::Instance& response) {
      40           0 :   AdminHtmlUtil::renderTableBegin(response);
      41           0 :   AdminHtmlUtil::renderEndpointTableRow(response, url_handler, params.query_, 1, !active_, active_);
      42           0 :   if (active_) {
      43           0 :     std::string buf;
      44           0 :     response.add(AdminHtmlUtil::getResource("active_params.html", buf));
      45           0 :   }
      46           0 :   AdminHtmlUtil::renderTableEnd(response);
      47           0 :   std::string buf;
      48           0 :   if (active_) {
      49           0 :     std::string buf2;
      50           0 :     response.addFragments({"<script>\n", AdminHtmlUtil::getResource("histograms.js", buf),
      51           0 :                            AdminHtmlUtil::getResource("active_stats.js", buf2), "</script>\n"});
      52           0 :   } else {
      53           0 :     response.addFragments(
      54           0 :         {"<script>\n", AdminHtmlUtil::getResource("histograms.js", buf), "</script>\n<pre>\n"});
      55           0 :   }
      56           0 : }
      57             : 
      58             : void StatsHtmlRender::generate(Buffer::Instance& response, const std::string& name,
      59           0 :                                const std::string& value) {
      60           0 :   ASSERT(first_histogram_);
      61           0 :   response.addFragments({name, ": \"", Html::Utility::sanitize(value), "\"\n"});
      62           0 : }
      63             : 
      64           0 : void StatsHtmlRender::noStats(Buffer::Instance& response, absl::string_view types) {
      65           0 :   ASSERT(first_histogram_);
      66           0 :   if (!active_) {
      67           0 :     response.addFragments({"</pre>\n<br/><i>No ", types, " found</i><br/>\n<pre>\n"});
      68           0 :   }
      69           0 : }
      70             : 
      71             : // When using Detailed mode, we override the generate method for HTML to trigger
      72             : // some JS that will render the histogram graphically. We will render that from
      73             : // JavaScript and convey the histogram data to the JS via JSON, so we can
      74             : // delegate to an instantiated JSON `sub-renderer` that will write into
      75             : // json_data_. that `sub_renderer` will only be populated in Detailed mode.
      76             : //
      77             : // All other modes default to rendering the histogram textually.
      78             : void StatsHtmlRender::generate(Buffer::Instance& response, const std::string& name,
      79           0 :                                const Stats::ParentHistogram& histogram) {
      80           0 :   if (json_histograms_) {
      81           0 :     Json::Streamer streamer(response);
      82             : 
      83             :     // If this is the first histogram we are rendering, then we need to first
      84             :     // generate the supported-percentiles array sand save it in a constant.
      85             :     //
      86             :     // We use a separate <script> tag for each histogram so that the browser can
      87             :     // begin parsing each potentially large histogram as it is generated,rather
      88             :     // than building up a huge json structure with all the histograms and
      89             :     // blocking rendering until that is parsed.
      90           0 :     if (first_histogram_) {
      91           0 :       first_histogram_ = false;
      92           0 :       response.add("</pre>\n<div id='histograms'></div>\n<script>\nconst supportedPercentiles = ");
      93           0 :       { StatsJsonRender::populateSupportedPercentiles(*streamer.makeRootArray()); }
      94           0 :       response.add(";\nconst histogramDiv = document.getElementById('histograms');\n");
      95             :       // The first histogram will share the first script tag with the histogram
      96             :       // div and supportedPercentiles array constants.
      97           0 :     } else {
      98           0 :       response.add("<script>\n");
      99           0 :     }
     100           0 :     response.add("renderHistogram(histogramDiv, supportedPercentiles,\n");
     101           0 :     { StatsJsonRender::generateHistogramDetail(name, histogram, *streamer.makeRootMap()); }
     102           0 :     response.add(");\n</script>\n");
     103           0 :   } else {
     104           0 :     StatsTextRender::generate(response, name, histogram);
     105           0 :   }
     106           0 : }
     107             : 
     108             : } // namespace Server
     109             : } // namespace Envoy