feat(smalltrip,problem): middleware support to set global handlers

smalltrip/problem/middleware.go

@@ -0,0 +1,32 @@
+package problem
+
+import (
+	"context"
+	"net/http"
+
+	"forge.capytal.company/loreddev/x/smalltrip/middleware"
+)
+
+func Middleware(h Handler) middleware.Middleware {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			ctx := context.WithValue(r.Context(), contextKey, h)
+			next.ServeHTTP(w, r.WithContext(ctx))
+		})
+	}
+}
+
+func HandlerMiddleware(fallback ...Handler) Handler {
+	return func(p Problem) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			handler := r.Context().Value(contextKey)
+			if h, ok := handler.(Handler); handler != nil && ok {
+				h(p).ServeHTTP(w, r)
+			} else if len(fallback) > 0 {
+				fallback[0](p).ServeHTTP(w, r)
+			}
+		})
+	}
+}
+
+var contextKey = "x-smalltrip-problems-middleware-handler"