Work on #61: Add support for ICMP

+ Update dependencies

vendor/k8s.io/apimachinery/pkg/labels/selector.go

@@ -26,7 +26,7 @@ import (
 	"k8s.io/apimachinery/pkg/selection"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/validation"
-	"k8s.io/klog"
+	"k8s.io/klog/v2"
 )
 
 // Requirements is AND of all requirements.
@@ -54,6 +54,11 @@ type Selector interface {
 
 	// Make a deep copy of the selector.
 	DeepCopySelector() Selector
+
+	// RequiresExactMatch allows a caller to introspect whether a given selector
+	// requires a single specific label to be set, and if so returns the value it
+	// requires.
+	RequiresExactMatch(label string) (value string, found bool)
 }
 
 // Everything returns a selector that matches all labels.
@@ -69,6 +74,9 @@ func (n nothingSelector) String() string                     { return "" }
 func (n nothingSelector) Add(_ ...Requirement) Selector      { return n }
 func (n nothingSelector) Requirements() (Requirements, bool) { return nil, false }
 func (n nothingSelector) DeepCopySelector() Selector         { return n }
+func (n nothingSelector) RequiresExactMatch(label string) (value string, found bool) {
+	return "", false
+}
 
 // Nothing returns a selector that matches no labels
 func Nothing() Selector {
@@ -162,7 +170,7 @@ func NewRequirement(key string, op selection.Operator, vals []string) (*Requirem
 	}
 
 	for i := range vals {
-		if err := validateLabelValue(vals[i]); err != nil {
+		if err := validateLabelValue(key, vals[i]); err != nil {
 			return nil, err
 		}
 	}
@@ -215,7 +223,7 @@ func (r *Requirement) Matches(ls Labels) bool {
 			return false
 		}
 
-		// There should be only one strValue in r.strValues, and can be converted to a integer.
+		// There should be only one strValue in r.strValues, and can be converted to an integer.
 		if len(r.strValues) != 1 {
 			klog.V(10).Infof("Invalid values count %+v of requirement %#v, for 'Gt', 'Lt' operators, exactly one value is required", len(r.strValues), r)
 			return false
@@ -358,6 +366,23 @@ func (lsel internalSelector) String() string {
 	return strings.Join(reqs, ",")
 }
 
+// RequiresExactMatch introspect whether a given selector requires a single specific field
+// to be set, and if so returns the value it requires.
+func (lsel internalSelector) RequiresExactMatch(label string) (value string, found bool) {
+	for ix := range lsel {
+		if lsel[ix].key == label {
+			switch lsel[ix].operator {
+			case selection.Equals, selection.DoubleEquals, selection.In:
+				if len(lsel[ix].strValues) == 1 {
+					return lsel[ix].strValues[0], true
+				}
+			}
+			return "", false
+		}
+	}
+	return "", false
+}
+
 // Token represents constant definition for lexer token
 type Token int
 
@@ -837,32 +862,39 @@ func validateLabelKey(k string) error {
 	return nil
 }
 
-func validateLabelValue(v string) error {
+func validateLabelValue(k, v string) error {
 	if errs := validation.IsValidLabelValue(v); len(errs) != 0 {
-		return fmt.Errorf("invalid label value: %q: %s", v, strings.Join(errs, "; "))
+		return fmt.Errorf("invalid label value: %q: at key: %q: %s", v, k, strings.Join(errs, "; "))
 	}
 	return nil
 }
 
 // SelectorFromSet returns a Selector which will match exactly the given Set. A
 // nil and empty Sets are considered equivalent to Everything().
+// It does not perform any validation, which means the server will reject
+// the request if the Set contains invalid values.
 func SelectorFromSet(ls Set) Selector {
+	return SelectorFromValidatedSet(ls)
+}
+
+// ValidatedSelectorFromSet returns a Selector which will match exactly the given Set. A
+// nil and empty Sets are considered equivalent to Everything().
+// The Set is validated client-side, which allows to catch errors early.
+func ValidatedSelectorFromSet(ls Set) (Selector, error) {
 	if ls == nil || len(ls) == 0 {
-		return internalSelector{}
+		return internalSelector{}, nil
 	}
-	var requirements internalSelector
+	requirements := make([]Requirement, 0, len(ls))
 	for label, value := range ls {
 		r, err := NewRequirement(label, selection.Equals, []string{value})
-		if err == nil {
-			requirements = append(requirements, *r)
-		} else {
-			//TODO: double check errors when input comes from serialization?
-			return internalSelector{}
+		if err != nil {
+			return nil, err
 		}
+		requirements = append(requirements, *r)
 	}
 	// sort to have deterministic string representation
 	sort.Sort(ByKey(requirements))
-	return requirements
+	return internalSelector(requirements), nil
 }
 
 // SelectorFromValidatedSet returns a Selector which will match exactly the given Set.
@@ -872,13 +904,13 @@ func SelectorFromValidatedSet(ls Set) Selector {
 	if ls == nil || len(ls) == 0 {
 		return internalSelector{}
 	}
-	var requirements internalSelector
+	requirements := make([]Requirement, 0, len(ls))
 	for label, value := range ls {
 		requirements = append(requirements, Requirement{key: label, operator: selection.Equals, strValues: []string{value}})
 	}
 	// sort to have deterministic string representation
 	sort.Sort(ByKey(requirements))
-	return requirements
+	return internalSelector(requirements)
 }
 
 // ParseToRequirements takes a string representing a selector and returns a list of