Not crazy about the design, but this works. Adding pprof's handlers

config.yml

@@ -1,5 +1,7 @@
 client:
+  # The maximum amount of references the client can send to test against (@todo)
   referencesMax: 100
+  # The maximum length (in bytes) of the "input" field, to accept to the finder.
   inputLengthMax: 50
 
 CORS:
@@ -9,8 +11,16 @@ CORS:
   #  - https://api.example.com
 
 server:
+  # The interface and port to listen on, "0.0.0.0" means all interfaces
   listenOn: "0.0.0.0:1337"
+  log:
+    # The minimum logging level
+    level: "info"
+  profiler:
+    enable: false
+    prefix: "debug"
 
+# The list of references
 references:
   domains:
     - gmail.com

main.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"net/http"
-	"os"
 
 	"github.com/Dynom/TySug/server"
 	"github.com/Dynom/TySug/server/service"
@@ -11,6 +10,8 @@ import (
 	"fmt"
 	"io/ioutil"
 
+	"os"
+
 	"gopkg.in/yaml.v2"
 )
 
@@ -26,6 +27,13 @@ type Config struct {
 	} `yaml:"CORS"`
 	Server struct {
 		ListenOn string `yaml:"listenOn"`
+		Log      struct {
+			Level string `yaml:"level"`
+		} `yaml:"log"`
+		Profiler struct {
+			Enable bool   `yaml:"enable"`
+			Prefix string `yaml:"prefix"`
+		} `yaml:"profiler"`
 	} `yaml:"server"`
 }
 
@@ -42,9 +50,18 @@ func main() {
 
 	logger := logrus.New()
 	logger.Formatter = &logrus.JSONFormatter{}
-	logger.Info("Starting up...")
-	logger.Level = logrus.DebugLevel
 	logger.Out = os.Stdout
+	logger.Level, err = logrus.ParseLevel(config.Server.Log.Level)
+
+	if err != nil {
+		panic(err)
+	}
+
+	logger.WithFields(logrus.Fields{
+		"client": config.Client,
+		"server": config.Server,
+		"CORS":   config.CORS,
+	}).Info("Starting up...")
 
 	sr := server.NewServiceRegistry()
 	for label, references := range config.References {
@@ -58,13 +75,21 @@ func main() {
 		sr.Register(label, svc)
 	}
 
-	s := server.NewHTTP(
-		sr,
-		http.NewServeMux(),
+	options := []server.Option{
 		server.WithLogger(logger),
 		server.WithCORS(config.CORS.AllowedOrigins),
 		server.WithInputLimitValidator(config.Client.InputLengthMax),
 		server.WithGzipHandler(),
+	}
+
+	if config.Server.Profiler.Enable {
+		options = append(options, server.WithPProf(config.Server.Profiler.Prefix))
+	}
+
+	s := server.NewHTTP(
+		sr,
+		*http.NewServeMux(),
+		options...,
 	)
 
 	err = s.ListenOnAndServe(config.Server.ListenOn)

server/http.go

@@ -11,6 +11,8 @@ import (
 
 	"errors"
 
+	"net/http/pprof"
+
 	"github.com/sirupsen/logrus"
 	"gopkg.in/tomb.v2"
 )
@@ -40,6 +42,11 @@ type tySugResponse struct {
 	Score  float64 `json:"score"`
 }
 
+type pprofConfig struct {
+	Enable bool
+	Prefix string
+}
+
 // Validator is a type to validate a client request, returning a nil errors means all went well.
 type Validator func(TSRequest tySugRequest) error
 
@@ -48,6 +55,7 @@ type TySugServer struct {
 	server     *http.Server
 	handlers   []func(h http.Handler) http.Handler
 	validators []Validator
+	profConfig pprofConfig
 
 	Logger *logrus.Logger
 }
@@ -60,7 +68,7 @@ func (tss *TySugServer) ListenOnAndServe(addr string) error {
 }
 
 // NewHTTP constructs a new TySugServer
-func NewHTTP(sr ServiceRegistry, mux *http.ServeMux, options ...Option) TySugServer {
+func NewHTTP(sr ServiceRegistry, mux http.ServeMux, options ...Option) TySugServer {
 	tySug := TySugServer{
 		Logger: logrus.StandardLogger(),
 	}
@@ -69,7 +77,7 @@ func NewHTTP(sr ServiceRegistry, mux *http.ServeMux, options ...Option) TySugSer
 		opt(&tySug)
 	}
 
-	var handler http.Handler = defaultHeaderHandler(createRequestIDHandler(mux))
+	var handler http.Handler = defaultHeaderHandler(createRequestIDHandler(&mux))
 	for _, h := range tySug.handlers {
 		handler = h(handler)
 	}
@@ -102,15 +110,37 @@ func NewHTTP(sr ServiceRegistry, mux *http.ServeMux, options ...Option) TySugSer
 	tySug.server = &http.Server{
 		ReadHeaderTimeout: 2 * time.Second,
 		ReadTimeout:       10 * time.Second,
-		WriteTimeout:      10 * time.Second,
+		WriteTimeout:      10 * time.Second, // Is overridden, when the profiler is enabled.
 		IdleTimeout:       60 * time.Second,
 		MaxHeaderBytes:    1 << 19, // 512 kb
 		Handler:           handler,
 	}
 
+	if tySug.profConfig.Enable {
+		configureProfiler(tySug, &mux, tySug.profConfig)
+	}
+
 	return tySug
 }
 
+func configureProfiler(s TySugServer, mux *http.ServeMux, c pprofConfig) {
+	var prefix string
+	if s.profConfig.Prefix != "" {
+		prefix = s.profConfig.Prefix
+	} else {
+		prefix = "debug"
+	}
+
+	mux.HandleFunc(`/`+prefix+`/pprof/`, pprof.Index)
+	mux.HandleFunc(`/`+prefix+`/pprof/cmdline`, pprof.Cmdline)
+	mux.HandleFunc(`/`+prefix+`/pprof/profile`, pprof.Profile)
+	mux.HandleFunc(`/`+prefix+`/pprof/symbol`, pprof.Symbol)
+	mux.HandleFunc(`/`+prefix+`/pprof/trace`, pprof.Trace)
+
+	// The profiler needs at least 30 seconds to use /prefix/pprof/profile
+	s.server.WriteTimeout = 31 * time.Second
+}
+
 func createRequestHandler(logger *logrus.Logger, svc Service, validators []Validator) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		t, ctx := tomb.WithContext(r.Context())

server/option.go

@@ -64,3 +64,11 @@ func WithGzipHandler() Option {
 		server.handlers = append(server.handlers, gziphandler.GzipHandler)
 	}
 }
+
+// WithPProf enables pprof
+func WithPProf(prefix string) Option {
+	return func(server *TySugServer) {
+		server.profConfig.Enable = true
+		server.profConfig.Prefix = prefix
+	}
+}