[#122] Add enabling versioning

New handlers:
PutBucketVersioning, GetBucketVersioning

Signed-off-by: Denis Kirillov <denis@nspcc.ru>

api/handler/versioning.go

@@ -0,0 +1,64 @@
+package handler
+
+import (
+	"encoding/xml"
+	"net/http"
+	"strconv"
+
+	"github.com/nspcc-dev/neofs-s3-gw/api"
+	"github.com/nspcc-dev/neofs-s3-gw/api/layer"
+	"go.uber.org/zap"
+)
+
+func (h *handler) PutBucketVersioningHandler(w http.ResponseWriter, r *http.Request) {
+	reqInfo := api.GetReqInfo(r.Context())
+
+	configuration := new(VersioningConfiguration)
+	if err := xml.NewDecoder(r.Body).Decode(configuration); err != nil {
+		h.logAndSendError(w, "couldn't decode versioning configuration", reqInfo, api.GetAPIError(api.ErrIllegalVersioningConfigurationException))
+		return
+	}
+
+	p := &layer.PutVersioningParams{
+		Bucket:            reqInfo.BucketName,
+		VersioningEnabled: configuration.Status == "Enabled",
+	}
+
+	if _, err := h.obj.PutBucketVersioning(r.Context(), p); err != nil {
+		h.logAndSendError(w, "couldn't put update versioning settings", reqInfo, err)
+	}
+}
+
+// GetBucketVersioningHandler implements bucket versioning getter handler.
+func (h *handler) GetBucketVersioningHandler(w http.ResponseWriter, r *http.Request) {
+	reqInfo := api.GetReqInfo(r.Context())
+
+	objInfo, err := h.obj.GetBucketVersioning(r.Context(), reqInfo.BucketName)
+	if err != nil {
+		h.log.Warn("couldn't get version settings object: default version settings will be used",
+			zap.String("request_id", reqInfo.RequestID),
+			zap.String("method", reqInfo.API),
+			zap.String("object_name", reqInfo.ObjectName),
+			zap.Error(err))
+	}
+
+	if err = api.EncodeToResponse(w, formVersioningConfiguration(objInfo)); err != nil {
+		h.logAndSendError(w, "something went wrong", reqInfo, err)
+	}
+}
+
+func formVersioningConfiguration(inf *layer.ObjectInfo) *VersioningConfiguration {
+	res := &VersioningConfiguration{Status: "Suspended"}
+
+	if inf == nil {
+		return res
+	}
+
+	enabled, ok := inf.Headers["S3-Settings-Versioning-enabled"]
+	if ok {
+		if parsed, err := strconv.ParseBool(enabled); err == nil && parsed {
+			res.Status = "Enabled"
+		}
+	}
+	return res
+}