github.com/minio/minio@v0.0.0-20240328213742-3f72439b8a27/internal/bucket/lifecycle/and.go (about)

     1  // Copyright (c) 2015-2021 MinIO, Inc.
     2  //
     3  // This file is part of MinIO Object Storage stack
     4  //
     5  // This program is free software: you can redistribute it and/or modify
     6  // it under the terms of the GNU Affero General Public License as published by
     7  // the Free Software Foundation, either version 3 of the License, or
     8  // (at your option) any later version.
     9  //
    10  // This program is distributed in the hope that it will be useful
    11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    13  // GNU Affero General Public License for more details.
    14  //
    15  // You should have received a copy of the GNU Affero General Public License
    16  // along with this program.  If not, see <http://www.gnu.org/licenses/>.
    17  
    18  package lifecycle
    19  
    20  import (
    21  	"encoding/xml"
    22  )
    23  
    24  var errDuplicateTagKey = Errorf("Duplicate Tag Keys are not allowed")
    25  
    26  // And - a tag to combine a prefix and multiple tags for lifecycle configuration rule.
    27  type And struct {
    28  	XMLName               xml.Name `xml:"And"`
    29  	ObjectSizeGreaterThan int64    `xml:"ObjectSizeGreaterThan,omitempty"`
    30  	ObjectSizeLessThan    int64    `xml:"ObjectSizeLessThan,omitempty"`
    31  	Prefix                Prefix   `xml:"Prefix,omitempty"`
    32  	Tags                  []Tag    `xml:"Tag,omitempty"`
    33  }
    34  
    35  // isEmpty returns true if Tags field is null
    36  func (a And) isEmpty() bool {
    37  	return len(a.Tags) == 0 && !a.Prefix.set &&
    38  		a.ObjectSizeGreaterThan == 0 && a.ObjectSizeLessThan == 0
    39  }
    40  
    41  // Validate - validates the And field
    42  func (a And) Validate() error {
    43  	// > This is used in a Lifecycle Rule Filter to apply a logical AND to two or more predicates.
    44  	// ref: https://docs.aws.amazon.com/AmazonS3/latest/API/API_LifecycleRuleAndOperator.html
    45  	// i.e, predCount >= 2
    46  	var predCount int
    47  	if a.Prefix.set {
    48  		predCount++
    49  	}
    50  	predCount += len(a.Tags)
    51  	if a.ObjectSizeGreaterThan > 0 {
    52  		predCount++
    53  	}
    54  	if a.ObjectSizeLessThan > 0 {
    55  		predCount++
    56  	}
    57  
    58  	if predCount < 2 {
    59  		return errXMLNotWellFormed
    60  	}
    61  
    62  	if a.ContainsDuplicateTag() {
    63  		return errDuplicateTagKey
    64  	}
    65  	for _, t := range a.Tags {
    66  		if err := t.Validate(); err != nil {
    67  			return err
    68  		}
    69  	}
    70  
    71  	if a.ObjectSizeGreaterThan < 0 || a.ObjectSizeLessThan < 0 {
    72  		return errXMLNotWellFormed
    73  	}
    74  	return nil
    75  }
    76  
    77  // ContainsDuplicateTag - returns true if duplicate keys are present in And
    78  func (a And) ContainsDuplicateTag() bool {
    79  	x := make(map[string]struct{}, len(a.Tags))
    80  
    81  	for _, t := range a.Tags {
    82  		if _, has := x[t.Key]; has {
    83  			return true
    84  		}
    85  		x[t.Key] = struct{}{}
    86  	}
    87  
    88  	return false
    89  }
    90  
    91  // BySize returns true when sz satisfies a
    92  // ObjectSizeLessThan/ObjectSizeGreaterthan or a logical AND of these predicates
    93  // Note: And combines size and other predicates like Tags, Prefix, etc. This
    94  // method applies exclusively to size predicates only.
    95  func (a And) BySize(sz int64) bool {
    96  	if a.ObjectSizeGreaterThan > 0 &&
    97  		sz <= a.ObjectSizeGreaterThan {
    98  		return false
    99  	}
   100  	if a.ObjectSizeLessThan > 0 &&
   101  		sz >= a.ObjectSizeLessThan {
   102  		return false
   103  	}
   104  	return true
   105  }