Added interfaces

1 files changed, 51 insertions, 0 deletions

diff --git a/wrap.go b/wrap.go
new file mode 100644
index 0000000..ab071cf
--- /dev/null
+++ b/wrap.go
@@ -0,0 +1,51 @@
+package api
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+)
+
+//Wrap API handler and returns standard http.HandlerFunc function
+func Wrap[RQ any, RS any](handler func(ctx context.Context, request *RQ) (RS, error)) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		req := new(RQ)
+		richifyRequest(req, r)
+		switch r.Method {
+		case http.MethodPost, http.MethodPatch, http.MethodDelete, http.MethodPut:
+			if err := json.NewDecoder(r.Body).Decode(req); err != nil {
+				w.WriteHeader(http.StatusBadRequest)
+				_, _ = w.Write([]byte(err.Error()))
+				return
+			}
+		}
+		resp, err := handler(r.Context(), req)
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			_, _ = w.Write([]byte(err.Error()))
+			return
+		}
+		if err := json.NewEncoder(w).Encode(resp); err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			_, _ = w.Write([]byte(err.Error()))
+			return
+		}
+	}
+}
+
+func richifyRequest[RQ any](req *RQ, baseRequest *http.Request) {
+	if v, ok := (any)(req).(WithHeader); ok {
+		v.WithHeader(baseRequest.Header)
+	}
+	if v, ok := (any)(req).(WithMethod); ok {
+		v.WithMethod(baseRequest.Method)
+	}
+}
+
+type WithHeader interface {
+	WithHeader(header http.Header)
+}
+
+type WithMethod interface {
+	WithMethod(method string)
+}