Refactor IDP code

common/handlers/observability.go

@@ -0,0 +1,56 @@
+package handlers
+
+import (
+	"context"
+	"net/http"
+	"sync/atomic"
+
+	log "github.com/sirupsen/logrus"
+)
+
+type key int
+
+const (
+	requestIdKey key = iota
+)
+
+func Logging(logger *log.Logger) func(http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			defer func() {
+				requestId, ok := r.Context().Value(requestIdKey).(string)
+				if !ok {
+					requestId = "unknown"
+				}
+				logger.Infoln(requestId, r.Method, r.URL.Path, r.RemoteAddr, r.UserAgent())
+			}()
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
+func Tracing(nextRequestId func() string) func(http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			requestId := r.Header.Get("X-Request-Id")
+			if requestId == "" {
+				requestId = nextRequestId()
+			}
+			ctx := context.WithValue(r.Context(), requestIdKey, requestId)
+			w.Header().Set("X-Request-Id", requestId)
+			next.ServeHTTP(w, r.WithContext(ctx))
+		})
+	}
+}
+
+var Healthy int32
+
+func NewHealthHandler() http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if atomic.LoadInt32(&Healthy) == 1 {
+			w.WriteHeader(http.StatusNoContent)
+			return
+		}
+		w.WriteHeader(http.StatusServiceUnavailable)
+	})
+}

common/handlers/security.go

@@ -0,0 +1,16 @@
+package handlers
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+)
+
+func EnableHSTS() func(http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("Strict-Transport-Security", fmt.Sprintf("max-age=%d", int((time.Hour*24*180).Seconds())))
+			next.ServeHTTP(w, r)
+		})
+	}
+}