Add a basic opinionated debug server

Author: nickstenning

debug/server.go

@@ -0,0 +1,49 @@
+package debug
+
+import (
+	"context"
+	"net/http"
+	"net/http/pprof"
+	"sync"
+
+	"github.com/replicate/go/logging"
+)
+
+var logger = logging.New("debug")
+
+var defaultServeMux http.ServeMux
+
+func init() {
+	defaultServeMux.HandleFunc("/debug/pprof/", pprof.Index)
+	defaultServeMux.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
+	defaultServeMux.HandleFunc("/debug/pprof/profile", pprof.Profile)
+	defaultServeMux.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
+	defaultServeMux.HandleFunc("/debug/pprof/trace", pprof.Trace)
+}
+
+type Server struct {
+	Addr string
+
+	once   sync.Once
+	server *http.Server
+}
+
+func (s *Server) init() {
+	s.server = &http.Server{
+		Addr:    s.Addr,
+		Handler: &defaultServeMux,
+	}
+}
+
+func (s *Server) ListenAndServe() error {
+	s.once.Do(s.init)
+
+	logger.Sugar().Infow("starting debug http server", "address", s.Addr)
+	return s.server.ListenAndServe()
+}
+
+func (s *Server) Shutdown(ctx context.Context) error {
+	s.once.Do(s.init)
+
+	return s.server.Shutdown(ctx)
+}