fill request with header and cookie data

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

util.go

@@ -0,0 +1,55 @@
+package http
+
+import (
+	"context"
+	"net/http"
+	"strings"
+
+	"go.unistack.org/micro/v3/metadata"
+	rutil "go.unistack.org/micro/v3/util/reflect"
+)
+
+func FillRequest(ctx context.Context, req interface{}, opts ...FillRequestOption) error {
+	var err error
+	options := handlerOptions{}
+	for _, o := range opts {
+		o(&options)
+	}
+	md, ok := metadata.FromIncomingContext(ctx)
+	if !ok {
+		return nil
+	}
+
+	for idx := 0; idx < len(options.headers)/2; idx += 2 {
+		k := http.CanonicalHeaderKey(options.headers[idx])
+		v, ok := md[k]
+		if !ok {
+			continue
+		}
+		if err = rutil.SetFieldByPath(req, v, k); err != nil {
+			return err
+		}
+	}
+
+	cookies := strings.Split(md["Cookie"], ";")
+	cmd := make(map[string]string, len(cookies))
+	for _, cookie := range cookies {
+		kv := strings.Split(cookie, "=")
+		if len(kv) != 2 {
+			continue
+		}
+		cmd[strings.TrimSpace(kv[0])] = strings.TrimSpace(kv[1])
+	}
+	for idx := 0; idx < len(options.cookies)/2; idx += 2 {
+		k := http.CanonicalHeaderKey(options.cookies[idx])
+		v, ok := cmd[k]
+		if !ok {
+			continue
+		}
+		if err = rutil.SetFieldByPath(req, v, k); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}