[#399] Add OPTIONS method for object operations

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

api/middleware/constants.go

@@ -5,7 +5,7 @@ const (
 
 	// bucket operations.
 
-	OptionsOperation                   = "Options"
+	OptionsBucketOperation             = "OptionsBucket"
 	HeadBucketOperation                = "HeadBucket"
 	ListMultipartUploadsOperation      = "ListMultipartUploads"
 	GetBucketLocationOperation         = "GetBucketLocation"
@@ -51,6 +51,7 @@ const (
 
 	// object operations.
 
+	OptionsObjectOperation           = "OptionsObject"
 	HeadObjectOperation              = "HeadObject"
 	ListPartsOperation               = "ListParts"
 	GetObjectACLOperation            = "GetObjectACL"

api/middleware/metrics.go

@@ -103,7 +103,7 @@ func stats(f http.HandlerFunc, resolveCID cidResolveFunc, appMetrics *metrics.Ap
 
 func requestTypeFromAPI(api string) metrics.RequestType {
 	switch api {
-	case OptionsOperation, HeadObjectOperation, HeadBucketOperation:
+	case OptionsBucketOperation, OptionsObjectOperation, HeadObjectOperation, HeadBucketOperation:
 		return metrics.HEADRequest
 	case CreateMultipartUploadOperation, UploadPartCopyOperation, UploadPartOperation, CompleteMultipartUploadOperation,
 		PutObjectACLOperation, PutObjectTaggingOperation, CopyObjectOperation, PutObjectRetentionOperation, PutObjectLegalHoldOperation,

api/middleware/policy.go

@@ -253,7 +253,7 @@ func determineBucketOperation(r *http.Request) string {
 	query := r.URL.Query()
 	switch r.Method {
 	case http.MethodOptions:
-		return OptionsOperation
+		return OptionsBucketOperation
 	case http.MethodHead:
 		return HeadBucketOperation
 	case http.MethodGet:
@@ -356,6 +356,8 @@ func determineBucketOperation(r *http.Request) string {
 func determineObjectOperation(r *http.Request) string {
 	query := r.URL.Query()
 	switch r.Method {
+	case http.MethodOptions:
+		return OptionsObjectOperation
 	case http.MethodHead:
 		return HeadObjectOperation
 	case http.MethodGet:

api/middleware/policy_test.go

@@ -91,9 +91,9 @@ func TestDetermineBucketOperation(t *testing.T) {
 		expected   string
 	}{
 		{
-			name:     "OptionsOperation",
+			name:     "OptionsBucketOperation",
 			method:   http.MethodOptions,
-			expected: OptionsOperation,
+			expected: OptionsBucketOperation,
 		},
 		{
 			name:     "HeadBucketOperation",
@@ -367,6 +367,11 @@ func TestDetermineObjectOperation(t *testing.T) {
 		headerKeys []string
 		expected   string
 	}{
+		{
+			name:     "OptionsObjectOperation",
+			method:   http.MethodOptions,
+			expected: OptionsObjectOperation,
+		},
 		{
 			name:     "HeadObjectOperation",
 			method:   http.MethodHead,