+ enable context tag propagation to http server metrics

instrumentation/kamon-akka-http/src/main/resources/reference.conf

@@ -50,6 +50,14 @@ kamon.instrumentation.akka.http {
       # metric will also have a status_code tag with the status code group (1xx, 2xx and so on).
       #
       #enabled = yes
+      #
+      # Metrics can also use tags from context; this will apply to the following subset of metrics:
+      #   - http.server.request
+      #   - http.server.request.active
+      #   - http.server.request.size
+      #   - http.server.response.size
+      #
+      #use-context-tags = no
     }
 
     #

instrumentation/kamon-akka-http/src/test/resources/application.conf

@@ -54,6 +54,14 @@ kamon.instrumentation.akka.http {
       # metric will also have a status_code tag with the status code group (1xx, 2xx and so on).
       #
       #enabled = yes
+      #
+      # Metrics can also use tags from context; this will apply to the following subset of metrics:
+      #   - http.server.request
+      #   - http.server.request.active
+      #   - http.server.request.size
+      #   - http.server.response.size
+      #
+      #use-context-tags = no
     }
 
 

instrumentation/kamon-instrumentation-common/src/main/resources/reference.conf

@@ -43,6 +43,14 @@ kamon {
           # metric will also have a status_code tag with the status code group (1xx, 2xx and so on).
           #
           enabled = yes
+          #
+          # Metrics can also use tags from context; this will apply to the following subset of metrics:
+          #   - http.server.request
+          #   - http.server.request.active
+          #   - http.server.request.size
+          #   - http.server.response.size
+          #
+          use-context-tags = no
         }
 
         #

instrumentation/kamon-instrumentation-common/src/main/scala/kamon/instrumentation/http/HttpServerInstrumentation.scala

@@ -27,6 +27,7 @@ import kamon.instrumentation.trace.SpanTagger.TagMode
 import kamon.instrumentation.tag.TagKeys
 import kamon.instrumentation.trace.SpanTagger
 import kamon.tag.Lookups.option
+import kamon.tag.TagSet
 import kamon.trace.Span
 import kamon.trace.Trace.SamplingDecision
 import kamon.util.Filter
@@ -152,6 +153,10 @@ object HttpServerInstrumentation {
       */
     def span: Span
 
+    /**
+     * Tag set to propagate to metrics from context
+     * */
+    def contextTagSet: TagSet
     /**
       * Signals that the entire request (headers and body) has been received.
       */
@@ -231,8 +236,11 @@ object HttpServerInstrumentation {
         incomingContext.withEntry(Span.Key, requestSpan)
       else incomingContext
 
+      val _contextTagSet: TagSet =
+        TagSet.from(settings.contextTagsForMetrics.collect{ case (k, TagMode.Metric) => handlerContext.getTag(option(k)).map(k -> _) }.flatten.toMap)
+
       _metrics.foreach { httpServerMetrics =>
-        httpServerMetrics.activeRequests.increment()
+        httpServerMetrics.activeRequests.withTags(_contextTagSet).increment()
       }
 
       new HttpServerInstrumentation.RequestHandler {
@@ -242,10 +250,12 @@ object HttpServerInstrumentation {
         override def span: Span =
           requestSpan
 
+        override def contextTagSet: TagSet = _contextTagSet
+
         override def requestReceived(receivedBytes: Long): RequestHandler = {
           if(receivedBytes >= 0) {
             _metrics.foreach { httpServerMetrics =>
-              httpServerMetrics.requestSize.record(receivedBytes)
+              httpServerMetrics.requestSize.withTags(contextTagSet).record(receivedBytes)
             }
           }
 
@@ -254,14 +264,14 @@ object HttpServerInstrumentation {
 
         override def buildResponse[HttpResponse](response: HttpMessage.ResponseBuilder[HttpResponse], context: Context): HttpResponse = {
           _metrics.foreach { httpServerMetrics =>
-            httpServerMetrics.countCompletedRequest(response.statusCode)
+            httpServerMetrics.countCompletedRequest(response.statusCode, contextTagSet)
           }
 
           if(!span.isEmpty) {
             settings.traceIDResponseHeader.foreach(traceIDHeader => response.write(traceIDHeader, span.trace.id.string))
             settings.spanIDResponseHeader.foreach(spanIDHeader => response.write(spanIDHeader, span.id.string))
             settings.httpServerResponseHeaderGenerator.headers(handlerContext).foreach(header => response.write(header._1, header._2))
-            
+
             SpanTagger.tag(span, TagKeys.HttpStatusCode, response.statusCode, settings.statusCodeTagMode)
 
             val statusCode = response.statusCode
@@ -275,10 +285,10 @@ object HttpServerInstrumentation {
 
         override def responseSent(sentBytes: Long): Unit = {
           _metrics.foreach { httpServerMetrics =>
-            httpServerMetrics.activeRequests.decrement()
+            httpServerMetrics.activeRequests.withTags(contextTagSet).decrement()
 
             if(sentBytes >= 0)
-              httpServerMetrics.responseSize.record(sentBytes)
+              httpServerMetrics.responseSize.withTags(contextTagSet).record(sentBytes)
           }
 
           span.finish()
@@ -336,7 +346,7 @@ object HttpServerInstrumentation {
             .foreach(tagValue => SpanTagger.tag(span, tagName, tagValue, mode))
       }
 
-      
+
       span.start()
     }
   }
@@ -359,9 +369,11 @@ object HttpServerInstrumentation {
     unhandledOperationName: String,
     operationMappings: Map[Filter.Glob, String],
     operationNameGenerator: HttpOperationNameGenerator,
-    httpServerResponseHeaderGenerator:HttpServerResponseHeaderGenerator
+    httpServerResponseHeaderGenerator:HttpServerResponseHeaderGenerator,
+    tagMetricsFromContext: Boolean
   ) {
     val operationNameSettings = OperationNameSettings(defaultOperationName, operationMappings, operationNameGenerator)
+    def contextTagsForMetrics: Map[String, TagMode] = if (tagMetricsFromContext) contextTags else Map.empty
   }
 
   object Settings {
@@ -375,6 +387,7 @@ object HttpServerInstrumentation {
 
       // HTTP Server metrics settings
       val enableServerMetrics = config.getBoolean("metrics.enabled")
+      val tagMetricsFromContext = config.getBoolean("metrics.use-context-tags")
 
       // Tracing settings
       val enableTracing = config.getBoolean("tracing.enabled")
@@ -435,7 +448,8 @@ object HttpServerInstrumentation {
         unhandledOperationName,
         operationMappings,
         operationNameGenerator.get,
-        httpServerResponseHeaderGenerator.get
+        httpServerResponseHeaderGenerator.get,
+        tagMetricsFromContext
       )
     }
   }

instrumentation/kamon-instrumentation-common/src/main/scala/kamon/instrumentation/http/HttpServerMetrics.scala

@@ -84,17 +84,17 @@ object HttpServerMetrics {
     /**
       * Increments the appropriate response counter depending on the the status code.
       */
-    def countCompletedRequest(statusCode: Int): Unit = {
+    def countCompletedRequest(statusCode: Int, contextTagSet: TagSet): Unit = {
       if(statusCode >= 200 && statusCode <= 299)
-        requestsSuccessful.increment()
+        requestsSuccessful.withTags(contextTagSet).increment()
       else if(statusCode >= 500 && statusCode <= 599)
-        requestsServerError.increment()
+        requestsServerError.withTags(contextTagSet).increment()
       else if(statusCode >= 400 && statusCode <= 499)
-        requestsClientError.increment()
+        requestsClientError.withTags(contextTagSet).increment()
       else if(statusCode >= 300 && statusCode <= 399)
-        requestsRedirection.increment()
+        requestsRedirection.withTags(contextTagSet).increment()
       else if(statusCode >= 100 && statusCode <= 199)
-        requestsInformational.increment()
+        requestsInformational.withTags(contextTagSet).increment()
       else {
         _logger.warn("Unknown HTTP status code {} found when recording HTTP server metrics", statusCode.toString)
       }

instrumentation/kamon-instrumentation-common/src/test/resources/application.conf

@@ -7,15 +7,20 @@ kamon {
   propagation.http.default {
     tags.mappings {
       "correlation-id" = "x-correlation-id"
+      "namespace" = "namespace"
     }
   }
 
   instrumentation {
     http-server {
       default {
+        metrics {
+          use-context-tags = yes
+        }
         tracing {
           preferred-trace-id-tag = "correlation-id"
           tags.from-context.peer = span
+          tags.from-context.namespace = metric
           response-headers {
             trace-id = "x-trace-id"
             span-id = "x-span-id"

instrumentation/kamon-instrumentation-common/src/test/scala/kamon/instrumentation/http/HttpServerInstrumentationSpec.scala

@@ -4,6 +4,7 @@ import java.time.Duration
 import com.typesafe.config.ConfigFactory
 import kamon.Kamon
 import kamon.context.Context
+import kamon.instrumentation.trace.SpanTagger.TagMode
 import kamon.tag.Lookups._
 import kamon.metric.{Counter, Histogram, RangeSampler, Timer}
 import kamon.testkit.{InitAndStopKamonAfterAll, InstrumentInspection, SpanInspection}
@@ -17,7 +18,7 @@ import org.scalatest.wordspec.AnyWordSpec
 import scala.collection.mutable
 
 class HttpServerInstrumentationSpec extends AnyWordSpec with Matchers with InstrumentInspection.Syntax with OptionValues
-    with SpanInspection.Syntax with Eventually with InitAndStopKamonAfterAll {
+  with SpanInspection.Syntax with Eventually with InitAndStopKamonAfterAll {
 
   "the HTTP server instrumentation" when {
     "configured for context propagation" should {
@@ -174,6 +175,21 @@ class HttpServerInstrumentationSpec extends AnyWordSpec with Matchers with Instr
         completedRequests(8081, 400).value() shouldBe 1L
         completedRequests(8081, 500).value() shouldBe 1L
       }
+
+      "populate context tags" in {
+        activeRequests(8081).distribution()
+
+        val handlerOne = httpServer().createHandler(fakeRequest("http://localhost:8080/", "/", "GET", Map("namespace" -> "env1")))
+        val handlerTwo = httpServer().createHandler(fakeRequest("http://localhost:8080/", "/", "GET", Map("namespace" -> "env1")))
+
+        handlerOne.contextTagSet.get(option("namespace")) shouldBe Some("env1")
+        handlerTwo.contextTagSet.get(option("namespace")) shouldBe Some("env1")
+        handlerOne.buildResponse(fakeResponse(200, mutable.Map.empty), Context.Empty)
+        handlerTwo.buildResponse(fakeResponse(200, mutable.Map.empty), Context.Empty)
+        handlerOne.responseSent(0L)
+        handlerTwo.responseSent(0L)
+
+      }
     }
 
     "configured for distributed tracing" should {

instrumentation/kamon-pekko-http/src/main/resources/reference.conf

@@ -50,6 +50,14 @@ kamon.instrumentation.pekko.http {
       # metric will also have a status_code tag with the status code group (1xx, 2xx and so on).
       #
       #enabled = yes
+      #
+      # Metrics can also use tags from context; this will apply to the following subset of metrics:
+      #   - http.server.request
+      #   - http.server.request.active
+      #   - http.server.request.size
+      #   - http.server.response.size
+      #
+      #use-context-tags = no
     }
 
     #

instrumentation/kamon-pekko-http/src/test/resources/application.conf

@@ -54,6 +54,13 @@ kamon.instrumentation.pekko.http {
       # metric will also have a status_code tag with the status code group (1xx, 2xx and so on).
       #
       #enabled = yes
+      #
+      # Metrics can also use tags from context; this will apply to the following subset of metrics:
+      #   - http.server.request
+      #   - http.server.request.active
+      #   - http.server.request.size
+      #   - http.server.response.size
+      #use-context-tags = no
     }
 
 

instrumentation/kamon-play/src/main/resources/reference.conf

@@ -41,6 +41,14 @@ kamon.instrumentation.play.http {
       # metric will also have a status_code tag with the status code group (1xx, 2xx and so on).
       #
       #enabled = yes
+      #
+      # Metrics can also use tags from context; this will apply to the following subset of metrics:
+      #   - http.server.request
+      #   - http.server.request.active
+      #   - http.server.request.size
+      #   - http.server.response.size
+      #
+      #use-context-tags = no
     }
 
 

instrumentation/kamon-spring/src/main/resources/reference.conf

@@ -49,6 +49,14 @@ kamon.instrumentation.spring {
       # metric will also have a status_code tag with the status code group (1xx, 2xx and so on).
       #
       enabled = yes
+      #
+      # Metrics can also use tags from context; this will apply to the following subset of metrics:
+      #   - http.server.request
+      #   - http.server.request.active
+      #   - http.server.request.size
+      #   - http.server.response.size
+      #
+      use-context-tags = no
     }
 
     #