simple handlerv0.0.2

1 files changed, 91 insertions, 0 deletions

diff --git a/handler.go b/handler.go
new file mode 100644
index 0000000..c7f9b66
--- /dev/null
+++ b/handler.go
@@ -0,0 +1,91 @@
+package mux
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+
+	"go.neonxp.ru/mux/ctxlib"
+)
+
+// Handler API handler and returns standard http.HandlerFunc function
+func Handler[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)
+		ctx := r.Context()
+		ctx = context.WithValue(ctx, ctxlib.Request, r)
+		ctx = context.WithValue(ctx, ctxlib.Method, r.Method)
+		ctx = context.WithValue(ctx, ctxlib.Headers, r.Header)
+
+		switch r.Method {
+		case http.MethodPost, http.MethodPatch, http.MethodDelete, http.MethodPut:
+			if err := Bind(r, req); err != nil {
+				w.WriteHeader(http.StatusBadRequest)
+				_, _ = w.Write([]byte(err.Error()))
+				return
+			}
+		}
+		resp, err := handler(ctx, req)
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			_, _ = w.Write([]byte(err.Error()))
+			return
+		}
+
+		statusCode := http.StatusOK
+		contentType := "application/json"
+		var body []byte
+
+		if v, ok := (any)(resp).(WithContentType); ok {
+			contentType = v.ContentType()
+		}
+		if v, ok := (any)(resp).(WithHTTPStatus); ok {
+			statusCode = v.Status()
+		}
+		if v, ok := (any)(resp).(Renderer); ok {
+			err = v.Render(ctx, w)
+			return
+		}
+
+		body, err = json.Marshal(resp)
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			_, _ = w.Write([]byte(err.Error()))
+			return
+		}
+		w.WriteHeader(statusCode)
+		w.Header().Set("Content-Type", contentType)
+		w.Write(body)
+
+	}
+}
+
+type NilRequest struct{}
+
+// WithContentType returns custom content type for response
+type WithContentType interface {
+	ContentType() string
+}
+
+// WithHTTPStatus returns custom status code
+type WithHTTPStatus interface {
+	Status() int
+}
+
+type RedirectResponse struct {
+	Code     int
+	Location string
+}
+
+func (rr *RedirectResponse) Render(ctx context.Context, w http.ResponseWriter) error {
+	w.Header().Add("Location", rr.Location)
+	w.WriteHeader(rr.Code)
+	return nil
+}
+
+func Redirect(code int, location string) *RedirectResponse {
+	return &RedirectResponse{
+		Code:     code,
+		Location: location,
+	}
+}