sigs.k8s.io/kubebuilder/v3@v3.14.0/pkg/config/version.go (about)

     1  /*
     2  Copyright 2022 The Kubernetes Authors.
     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 config
    18  
    19  import (
    20  	"encoding/json"
    21  	"errors"
    22  	"fmt"
    23  	"strconv"
    24  	"strings"
    25  
    26  	"sigs.k8s.io/kubebuilder/v3/pkg/model/stage"
    27  )
    28  
    29  var (
    30  	errNonPositive = errors.New("project version number must be positive")
    31  	errEmpty       = errors.New("project version is empty")
    32  )
    33  
    34  // Version is a project version containing a non-zero positive integer and a stage value that represents stability.
    35  type Version struct {
    36  	// Number denotes the current version of a plugin. Two different numbers between versions
    37  	// indicate that they are incompatible.
    38  	Number int
    39  	// Stage indicates stability.
    40  	Stage stage.Stage
    41  }
    42  
    43  // Parse parses version inline, assuming it adheres to format: [1-9][0-9]*(-(alpha|beta))?
    44  func (v *Version) Parse(version string) error {
    45  	if len(version) == 0 {
    46  		return errEmpty
    47  	}
    48  
    49  	substrings := strings.SplitN(version, "-", 2)
    50  
    51  	var err error
    52  	if v.Number, err = strconv.Atoi(substrings[0]); err != nil {
    53  		// Lets check if the `-` belonged to a negative number
    54  		if n, err := strconv.Atoi(version); err == nil && n < 0 {
    55  			return errNonPositive
    56  		}
    57  		return err
    58  	} else if v.Number == 0 {
    59  		return errNonPositive
    60  	}
    61  
    62  	if len(substrings) > 1 {
    63  		if err = v.Stage.Parse(substrings[1]); err != nil {
    64  			return err
    65  		}
    66  	}
    67  
    68  	return nil
    69  }
    70  
    71  // String returns the string representation of v.
    72  func (v Version) String() string {
    73  	stageStr := v.Stage.String()
    74  	if len(stageStr) == 0 {
    75  		return fmt.Sprintf("%d", v.Number)
    76  	}
    77  	return fmt.Sprintf("%d-%s", v.Number, stageStr)
    78  }
    79  
    80  // Validate ensures that the version number is positive and the stage is one of the valid stages.
    81  func (v Version) Validate() error {
    82  	if v.Number < 1 {
    83  		return errNonPositive
    84  	}
    85  
    86  	return v.Stage.Validate()
    87  }
    88  
    89  // Compare returns -1 if v < other, 0 if v == other, and 1 if v > other.
    90  func (v Version) Compare(other Version) int {
    91  	if v.Number > other.Number {
    92  		return 1
    93  	} else if v.Number < other.Number {
    94  		return -1
    95  	}
    96  
    97  	return v.Stage.Compare(other.Stage)
    98  }
    99  
   100  // IsStable returns true if v is stable.
   101  func (v Version) IsStable() bool {
   102  	return v.Stage.IsStable()
   103  }
   104  
   105  // MarshalJSON implements json.Marshaller
   106  func (v Version) MarshalJSON() ([]byte, error) {
   107  	if err := v.Validate(); err != nil {
   108  		return []byte{}, err
   109  	}
   110  
   111  	return json.Marshal(v.String())
   112  }
   113  
   114  // UnmarshalJSON implements json.Unmarshaller
   115  func (v *Version) UnmarshalJSON(b []byte) error {
   116  	var str string
   117  	if err := json.Unmarshal(b, &str); err != nil {
   118  		return err
   119  	}
   120  
   121  	return v.Parse(str)
   122  }