github.com/timstclair/heapster@v0.20.0-alpha1/Godeps/_workspace/src/k8s.io/kubernetes/pkg/apis/extensions/helpers.go (about)

     1  /*
     2  Copyright 2015 The Kubernetes Authors All rights reserved.
     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 extensions
    18  
    19  import (
    20  	"fmt"
    21  
    22  	"sort"
    23  
    24  	"k8s.io/kubernetes/pkg/labels"
    25  	"k8s.io/kubernetes/pkg/util/sets"
    26  )
    27  
    28  // PodSelectorAsSelector converts the PodSelector api type into a struct that implements
    29  // labels.Selector
    30  func PodSelectorAsSelector(ps *PodSelector) (labels.Selector, error) {
    31  	if ps == nil {
    32  		return labels.Nothing(), nil
    33  	}
    34  	if len(ps.MatchLabels)+len(ps.MatchExpressions) == 0 {
    35  		return labels.Everything(), nil
    36  	}
    37  	selector := labels.LabelSelector{}
    38  	for k, v := range ps.MatchLabels {
    39  		req, err := labels.NewRequirement(k, labels.InOperator, sets.NewString(v))
    40  		if err != nil {
    41  			return nil, err
    42  		}
    43  		selector = append(selector, *req)
    44  	}
    45  	for _, expr := range ps.MatchExpressions {
    46  		var op labels.Operator
    47  		switch expr.Operator {
    48  		case PodSelectorOpIn:
    49  			op = labels.InOperator
    50  		case PodSelectorOpNotIn:
    51  			op = labels.NotInOperator
    52  		case PodSelectorOpExists:
    53  			op = labels.ExistsOperator
    54  		case PodSelectorOpDoesNotExist:
    55  			op = labels.DoesNotExistOperator
    56  		default:
    57  			return nil, fmt.Errorf("%q is not a valid pod selector operator", expr.Operator)
    58  		}
    59  		req, err := labels.NewRequirement(expr.Key, op, sets.NewString(expr.Values...))
    60  		if err != nil {
    61  			return nil, err
    62  		}
    63  		selector = append(selector, *req)
    64  	}
    65  	sort.Sort(labels.ByKey(selector))
    66  	return selector, nil
    67  }