storj.io/minio@v0.0.0-20230509071714-0cbc90f649b1/pkg/bucket/lifecycle/tag.go (about) 1 /* 2 * MinIO Cloud Storage, (C) 2019 MinIO, Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package lifecycle 18 19 import ( 20 "encoding/xml" 21 "io" 22 "unicode/utf8" 23 ) 24 25 // Tag - a tag for a lifecycle configuration Rule filter. 26 type Tag struct { 27 XMLName xml.Name `xml:"Tag"` 28 Key string `xml:"Key,omitempty"` 29 Value string `xml:"Value,omitempty"` 30 } 31 32 var ( 33 errInvalidTagKey = Errorf("The TagKey you have provided is invalid") 34 errInvalidTagValue = Errorf("The TagValue you have provided is invalid") 35 36 errDuplicatedXMLTag = Errorf("duplicated XML Tag") 37 errUnknownXMLTag = Errorf("unknown XML Tag") 38 ) 39 40 // UnmarshalXML - decodes XML data. 41 func (tag *Tag) UnmarshalXML(d *xml.Decoder, start xml.StartElement) (err error) { 42 var keyAlreadyParsed, valueAlreadyParsed bool 43 for { 44 // Read tokens from the XML document in a stream. 45 t, err := d.Token() 46 if err != nil { 47 if err == io.EOF { 48 break 49 } 50 return err 51 } 52 53 switch se := t.(type) { 54 case xml.StartElement: 55 var s string 56 if err = d.DecodeElement(&s, &se); err != nil { 57 return err 58 } 59 switch se.Name.Local { 60 case "Key": 61 if keyAlreadyParsed { 62 return errDuplicatedXMLTag 63 } 64 tag.Key = s 65 keyAlreadyParsed = true 66 case "Value": 67 if valueAlreadyParsed { 68 return errDuplicatedXMLTag 69 } 70 tag.Value = s 71 valueAlreadyParsed = true 72 default: 73 return errUnknownXMLTag 74 } 75 } 76 } 77 78 return nil 79 } 80 81 func (tag Tag) String() string { 82 return tag.Key + "=" + tag.Value 83 } 84 85 // IsEmpty returns whether this tag is empty or not. 86 func (tag Tag) IsEmpty() bool { 87 return tag.Key == "" 88 } 89 90 // Validate checks this tag. 91 func (tag Tag) Validate() error { 92 if len(tag.Key) == 0 || utf8.RuneCountInString(tag.Key) > 128 { 93 return errInvalidTagKey 94 } 95 96 if utf8.RuneCountInString(tag.Value) > 256 { 97 return errInvalidTagValue 98 } 99 100 return nil 101 }