register pprof endpoints for allocator (#1408)

* register pprof endpoints for allocator

* changelog entry

* full sentence for changelog

.chloggen/allocator-pprof.yaml

@@ -0,0 +1,16 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. operator, target allocator, github action)
+component: target allocator
+
+# A brief description of the change. Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Register pprof endpoints under `/debug/pprof`.
+
+# One or more tracking issues related to the change
+issues: [188]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

cmd/otel-allocator/server/server.go

@@ -19,6 +19,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
+	"net/http/pprof"
 	"net/url"
 	"time"
 
@@ -78,6 +79,7 @@ func NewServer(log logr.Logger, allocator allocation.Allocator, discoveryManager
 	router.GET("/jobs", s.JobHandler)
 	router.GET("/jobs/:job_id/targets", s.TargetsHandler)
 	router.GET("/metrics", gin.WrapH(promhttp.Handler()))
+	registerPprof(router.Group("/debug/pprof/"))
 
 	s.server = &http.Server{Addr: *listenAddr, Handler: router, ReadHeaderTimeout: 90 * time.Second}
 	return s
@@ -192,3 +194,11 @@ func GetAllTargetsByJob(allocator allocation.Allocator, job string) map[string]c
 	}
 	return displayData
 }
+
+func registerPprof(g *gin.RouterGroup) {
+	g.GET("/", gin.WrapF(pprof.Index))
+	g.GET("/cmdline", gin.WrapF(pprof.Cmdline))
+	g.GET("/profile", gin.WrapF(pprof.Profile))
+	g.GET("/symbol", gin.WrapF(pprof.Symbol))
+	g.GET("/trace", gin.WrapF(pprof.Trace))
+}