src/main/kotlin/net/pterodactylus/sone/web/pages/MetricsPage.kt

   1 package net.pterodactylus.sone.web.pages
   2
   3 import com.codahale.metrics.*
   4 import net.pterodactylus.sone.main.*
   5 import net.pterodactylus.sone.web.*
   6 import net.pterodactylus.sone.web.page.*
   7 import net.pterodactylus.util.template.*
   8 import javax.inject.*
   9
  10 @MenuName("Metrics")
  11 @TemplatePath("/templates/metrics.html")
  12 @ToadletPath("metrics.html")
  13 class MetricsPage @Inject constructor(webInterface: WebInterface, loaders: Loaders, templateRenderer: TemplateRenderer, private val metricsRegistry: MetricRegistry) : SoneTemplatePage(webInterface, loaders, templateRenderer, "Page.Metrics.Title") {
  14
  15         override fun handleRequest(soneRequest: SoneRequest, templateContext: TemplateContext) {
  16                 metricsRegistry.histograms
  17                                 .mapKeys { it.key to it.key.toI18n() }
  18                                 .onEach { addHistogram(templateContext, it.key.first, it.key.second) }
  19                                 .keys
  20                                 .map(Pair<*, String>::second)
  21                                 .let { templateContext["histogramKeys"] = it }
  22         }
  23
  24         private fun addHistogram(templateContext: TemplateContext, metricName: String, variablePrefix: String) {
  25                 metricsRegistry.histogram(metricName).also { histogram ->
  26                         templateContext["${variablePrefix}I18n"] = variablePrefix.capitalizeFirst()
  27                         templateContext["${variablePrefix}Count"] = histogram.count
  28                         histogram.snapshot.also { snapshot ->
  29                                 templateContext["${variablePrefix}Min"] = snapshot.min
  30                                 templateContext["${variablePrefix}Max"] = snapshot.max
  31                                 templateContext["${variablePrefix}Median"] = snapshot.median
  32                                 templateContext["${variablePrefix}Mean"] = snapshot.mean
  33                                 templateContext["${variablePrefix}Percentile75"] = snapshot.get75thPercentile()
  34                                 templateContext["${variablePrefix}Percentile95"] = snapshot.get95thPercentile()
  35                                 templateContext["${variablePrefix}Percentile98"] = snapshot.get98thPercentile()
  36                                 templateContext["${variablePrefix}Percentile99"] = snapshot.get99thPercentile()
  37                                 templateContext["${variablePrefix}Percentile999"] = snapshot.get999thPercentile()
  38                         }
  39                 }
  40         }
  41
  42 }
  43
  44 private fun String.toI18n() = split(".")
  45                 .mapIndexed { index, s -> if (index > 0) s.capitalizeFirst() else s }
  46                 .joinToString("")
  47
  48 private fun String.capitalizeFirst() =
  49                 get(0).toUpperCase() + if (length > 0) {
  50                         substring(1)
  51                 } else {
  52                         ""
  53                 }