github.com/netdata/go.d.plugin@v0.58.1/pkg/prometheus/selector/logical.go (about)

     1  // SPDX-License-Identifier: GPL-3.0-or-later
     2  
     3  package selector
     4  
     5  import (
     6  	"github.com/prometheus/prometheus/model/labels"
     7  )
     8  
     9  type (
    10  	trueSelector  struct{}
    11  	falseSelector struct{}
    12  	negSelector   struct{ s Selector }
    13  	andSelector   struct{ lhs, rhs Selector }
    14  	orSelector    struct{ lhs, rhs Selector }
    15  )
    16  
    17  func (trueSelector) Matches(_ labels.Labels) bool    { return true }
    18  func (falseSelector) Matches(_ labels.Labels) bool   { return false }
    19  func (s negSelector) Matches(lbs labels.Labels) bool { return !s.s.Matches(lbs) }
    20  func (s andSelector) Matches(lbs labels.Labels) bool { return s.lhs.Matches(lbs) && s.rhs.Matches(lbs) }
    21  func (s orSelector) Matches(lbs labels.Labels) bool  { return s.lhs.Matches(lbs) || s.rhs.Matches(lbs) }
    22  
    23  // True returns a selector which always returns true
    24  func True() Selector {
    25  	return trueSelector{}
    26  }
    27  
    28  // And returns a selector which returns true only if all of it's sub-selectors return true
    29  func And(lhs, rhs Selector, others ...Selector) Selector {
    30  	s := andSelector{lhs: lhs, rhs: rhs}
    31  	if len(others) == 0 {
    32  		return s
    33  	}
    34  	return And(s, others[0], others[1:]...)
    35  }
    36  
    37  // Or returns a selector which returns true if any of it's sub-selectors return true
    38  func Or(lhs, rhs Selector, others ...Selector) Selector {
    39  	s := orSelector{lhs: lhs, rhs: rhs}
    40  	if len(others) == 0 {
    41  		return s
    42  	}
    43  	return Or(s, others[0], others[1:]...)
    44  }
    45  
    46  // Not returns a selector which returns the negation of the sub-selector's result
    47  func Not(s Selector) Selector {
    48  	return negSelector{s}
    49  }