api: fix upload to handle attributes FilePath, FileName

When we receive headers, they are automatically formatted from any case to
only the first letter being uppercase. For example, `FilePath` transforms into
`Filepath`. However, NEOFS is case-sensitive for these attributes, which is why
we intentionally change them to CamelCase style. We hope this is a temporary
workaround and will be removed asap.
Connected to nspcc-dev/neofs-http-gw#255.

Signed-off-by: Tatiana Nesterenko <tatiana@nspcc.io>

handlers/objects.go

@@ -42,6 +42,9 @@ const (
 	attributeFilePath         = "FilePath"
 	sizeToDetectType          = 512
 	userAttributeHeaderPrefix = "X-Attribute-"
+
+	attributeFilepathHTTP = "Filepath"
+	attributeFilenameHTTP = "Filename"
 )
 
 type readCloser struct {

handlers/util.go

@@ -291,6 +291,7 @@ func filterHeaders(l *zap.Logger, header http.Header) (map[string]string, error)
 			continue
 		}
 
+		clearKey = formatSpecialAttribute(clearKey)
 		result[clearKey] = value
 
 		l.Debug("add attribute to result object",
@@ -299,3 +300,17 @@ func filterHeaders(l *zap.Logger, header http.Header) (map[string]string, error)
 	}
 	return result, nil
 }
+
+// formatSpecialAttribute checks if a key-string is one of the special NEOFS
+// attributes and returns the string in the correct case.
+// For example: "Filepath" -> "FilePath".
+func formatSpecialAttribute(s string) string {
+	switch s {
+	case attributeFilepathHTTP:
+		return attributeFilePath
+	case attributeFilenameHTTP:
+		return object.AttributeFileName
+	default:
+		return s
+	}
+}

handlers/util_test.go

@@ -191,16 +191,24 @@ func TestFilter(t *testing.T) {
 	req.Set("X-Attribute-Neofs-Expiration-Epoch1", "101")
 	req.Set("X-Attribute-NEOFS-Expiration-Epoch2", "102")
 	req.Set("X-Attribute-neofs-Expiration-Epoch3", "103")
+	req.Set("X-Attribute-FileName", "FileName") // This one will be overridden.
+	req.Set("X-Attribute-filename", "filename")
+	req.Set("X-Attribute-fIlePaTh", "fIlePaTh/") // This one will be overridden.
+	req.Set("X-Attribute-Filepath", "Filepath/")
+	req.Set("X-Attribute-FilePath1", "FilePath/1")
 	req.Set("X-Attribute-My-Attribute", "value")
 	req.Set("X-Attribute-MyAttribute", "value2")
-	req.Set("X-Attribute-Empty-Value", "")
-	req.Set("X-Attribute-", "prefix only")
-	req.Set("No-Prefix", "value")
+	req.Set("X-Attribute-Empty-Value", "") // This one will be skipped.
+	req.Set("X-Attribute-", "prefix only") // This one will be skipped.
+	req.Set("No-Prefix", "value")          // This one will be skipped.
 
 	expected := map[string]string{
 		"__NEOFS__EXPIRATION_EPOCH1": "101",
 		"__NEOFS__EXPIRATION_EPOCH2": "102",
 		"__NEOFS__EXPIRATION_EPOCH3": "103",
+		"FileName":                   "filename",
+		"FilePath":                   "Filepath/",
+		"Filepath1":                  "FilePath/1",
 		"My-Attribute":               "value",
 		"Myattribute":                "value2",
 	}

spec/rest.yaml

@@ -644,6 +644,16 @@ paths:
           required: false
           type: file
           description: The file to upload.  If no file is present in this field, any other field name will be accepted, except for an empty one.
+        - name: X-Attribute-Filename
+          in: header
+          required: false
+          type: string
+          description: This attribute, in any combination of upper/lower case, will be added to the object as the `FileName` attribute. It will also be returned as the `FileName` attribute in GET/HEAD API calls for the object (/get/{containerId}/{objectId}) and the `name` in POST call search in a container (/objects/{containerId}/search).
+        - name: X-Attribute-Filepath
+          in: header
+          required: false
+          type: string
+          description: This attribute, in any combination of upper/lower case, will be added to the object as the `FilePath` attribute. It will also be returned as the `FilePath` attribute in GET/HEAD API calls for the object (/get/{containerId}/{objectId}) or the `filePath` in POST call search in a container (/objects/{containerId}/search).
       responses:
         200:
           headers: