[#73] Uploader, downloader structures refactoring

Signed-off-by: Marina Biryukova <m.biryukova@yadro.com>

internal/handler/utils.go

@@ -0,0 +1,60 @@
+package handler
+
+import (
+	"context"
+	"strings"
+	"time"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-http-gw/internal/logs"
+	"git.frostfs.info/TrueCloudLab/frostfs-http-gw/response"
+	"git.frostfs.info/TrueCloudLab/frostfs-http-gw/tokens"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/bearer"
+	"github.com/valyala/fasthttp"
+	"go.uber.org/zap"
+)
+
+type request struct {
+	*fasthttp.RequestCtx
+	log *zap.Logger
+}
+
+func (r *request) handleFrostFSErr(err error, start time.Time) {
+	logFields := []zap.Field{
+		zap.Stringer("elapsed", time.Since(start)),
+		zap.Error(err),
+	}
+	statusCode, msg, additionalFields := response.FormErrorResponse("could not receive object", err)
+	logFields = append(logFields, additionalFields...)
+
+	r.log.Error(logs.CouldNotReceiveObject, logFields...)
+	response.Error(r.RequestCtx, msg, statusCode)
+}
+
+func bearerToken(ctx context.Context) *bearer.Token {
+	if tkn, err := tokens.LoadBearerToken(ctx); err == nil {
+		return tkn
+	}
+	return nil
+}
+
+func isValidToken(s string) bool {
+	for _, c := range s {
+		if c <= ' ' || c > 127 {
+			return false
+		}
+		if strings.ContainsRune("()<>@,;:\\\"/[]?={}", c) {
+			return false
+		}
+	}
+	return true
+}
+
+func isValidValue(s string) bool {
+	for _, c := range s {
+		// HTTP specification allows for more technically, but we don't want to escape things.
+		if c < ' ' || c > 127 || c == '"' {
+			return false
+		}
+	}
+	return true
+}