log reponse codes

server/ctrlbase/ctrl.go

@@ -1,12 +1,47 @@
 package ctrlbase
 
 import (
+	"fmt"
 	"log"
 	"net/http"
 
 	"senan.xyz/g/gonic/db"
 )
 
+type statusWriter struct {
+	http.ResponseWriter
+	status int
+}
+
+func (w *statusWriter) WriteHeader(status int) {
+	w.status = status
+	w.ResponseWriter.WriteHeader(status)
+}
+
+func (w *statusWriter) Write(b []byte) (int, error) {
+	if w.status == 0 {
+		w.status = 200
+	}
+	return w.ResponseWriter.Write(b)
+}
+
+func statusToBlock(code int) string {
+	var bg int
+	switch {
+	case 200 <= code && code <= 299:
+		bg = 42 // bright green, ok
+	case 300 <= code && code <= 399:
+		bg = 46 // bright cyan, redirect
+	case 400 <= code && code <= 499:
+		bg = 43 // bright orange, client error
+	case 500 <= code && code <= 599:
+		bg = 41 // bright red, server error
+	default:
+		bg = 47 // bright white (grey)
+	}
+	return fmt.Sprintf("\u001b[%d;1m %d \u001b[0m", bg, code)
+}
+
 type Controller struct {
 	DB        *db.DB
 	MusicPath string
@@ -14,8 +49,12 @@ type Controller struct {
 
 func (c *Controller) WithLogging(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		log.Printf("connection from `%s` for `%s`", r.RemoteAddr, r.URL)
+		// this is (should be) the first middleware. pass right though it
-		next.ServeHTTP(w, r)
+		// by calling `next` first instead of last. when it completes all
+		// other middlewares and the custom ResponseWriter has been written
+		sw := &statusWriter{ResponseWriter: w}
+		next.ServeHTTP(sw, r)
+		log.Printf("response %s for `%s`", statusToBlock(sw.status), r.URL)
 	})
 }