kubectl taint: copy core taintutil dependency into kubectl

pkg/kubectl/cmd/taint/utils.go

@@ -0,0 +1,209 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package taints implements utilites for working with taints
+package taint
+
+import (
+	"fmt"
+	"strings"
+
+	corev1 "k8s.io/api/core/v1"
+	utilerrors "k8s.io/apimachinery/pkg/util/errors"
+	"k8s.io/apimachinery/pkg/util/sets"
+	"k8s.io/apimachinery/pkg/util/validation"
+)
+
+// Exported taint constant strings
+const (
+	MODIFIED  = "modified"
+	TAINTED   = "tainted"
+	UNTAINTED = "untainted"
+)
+
+// parseTaints takes a spec which is an array and creates slices for new taints to be added, taints to be deleted.
+func parseTaints(spec []string) ([]corev1.Taint, []corev1.Taint, error) {
+	var taints, taintsToRemove []corev1.Taint
+	uniqueTaints := map[corev1.TaintEffect]sets.String{}
+
+	for _, taintSpec := range spec {
+		if strings.Index(taintSpec, "=") != -1 && strings.Index(taintSpec, ":") != -1 {
+			newTaint, err := parseTaint(taintSpec)
+			if err != nil {
+				return nil, nil, err
+			}
+			// validate if taint is unique by <key, effect>
+			if len(uniqueTaints[newTaint.Effect]) > 0 && uniqueTaints[newTaint.Effect].Has(newTaint.Key) {
+				return nil, nil, fmt.Errorf("duplicated taints with the same key and effect: %v", newTaint)
+			}
+			// add taint to existingTaints for uniqueness check
+			if len(uniqueTaints[newTaint.Effect]) == 0 {
+				uniqueTaints[newTaint.Effect] = sets.String{}
+			}
+			uniqueTaints[newTaint.Effect].Insert(newTaint.Key)
+
+			taints = append(taints, newTaint)
+		} else if strings.HasSuffix(taintSpec, "-") {
+			taintKey := taintSpec[:len(taintSpec)-1]
+			var effect corev1.TaintEffect
+			if strings.Index(taintKey, ":") != -1 {
+				parts := strings.Split(taintKey, ":")
+				taintKey = parts[0]
+				effect = corev1.TaintEffect(parts[1])
+			}
+
+			// If effect is specified, need to validate it.
+			if len(effect) > 0 {
+				err := validateTaintEffect(effect)
+				if err != nil {
+					return nil, nil, err
+				}
+			}
+			taintsToRemove = append(taintsToRemove, corev1.Taint{Key: taintKey, Effect: effect})
+		} else {
+			return nil, nil, fmt.Errorf("unknown taint spec: %v", taintSpec)
+		}
+	}
+	return taints, taintsToRemove, nil
+}
+
+// parseTaint parses a taint from a string. Taint must be of the format '<key>=<value>:<effect>'.
+func parseTaint(st string) (corev1.Taint, error) {
+	var taint corev1.Taint
+	parts := strings.Split(st, "=")
+	if len(parts) != 2 || len(parts[1]) == 0 || len(validation.IsQualifiedName(parts[0])) > 0 {
+		return taint, fmt.Errorf("invalid taint spec: %v", st)
+	}
+
+	parts2 := strings.Split(parts[1], ":")
+
+	errs := validation.IsValidLabelValue(parts2[0])
+	if len(parts2) != 2 || len(errs) != 0 {
+		return taint, fmt.Errorf("invalid taint spec: %v, %s", st, strings.Join(errs, "; "))
+	}
+
+	effect := corev1.TaintEffect(parts2[1])
+	if err := validateTaintEffect(effect); err != nil {
+		return taint, err
+	}
+
+	taint.Key = parts[0]
+	taint.Value = parts2[0]
+	taint.Effect = effect
+
+	return taint, nil
+}
+
+func validateTaintEffect(effect corev1.TaintEffect) error {
+	if effect != corev1.TaintEffectNoSchedule && effect != corev1.TaintEffectPreferNoSchedule && effect != corev1.TaintEffectNoExecute {
+		return fmt.Errorf("invalid taint effect: %v, unsupported taint effect", effect)
+	}
+
+	return nil
+}
+
+// ReorganizeTaints returns the updated set of taints, taking into account old taints that were not updated,
+// old taints that were updated, old taints that were deleted, and new taints.
+func reorganizeTaints(node *corev1.Node, overwrite bool, taintsToAdd []corev1.Taint, taintsToRemove []corev1.Taint) (string, []corev1.Taint, error) {
+	newTaints := append([]corev1.Taint{}, taintsToAdd...)
+	oldTaints := node.Spec.Taints
+	// add taints that already existing but not updated to newTaints
+	added := addTaints(oldTaints, &newTaints)
+	allErrs, deleted := deleteTaints(taintsToRemove, &newTaints)
+	if (added && deleted) || overwrite {
+		return MODIFIED, newTaints, utilerrors.NewAggregate(allErrs)
+	} else if added {
+		return TAINTED, newTaints, utilerrors.NewAggregate(allErrs)
+	}
+	return UNTAINTED, newTaints, utilerrors.NewAggregate(allErrs)
+}
+
+// deleteTaints deletes the given taints from the node's taintlist.
+func deleteTaints(taintsToRemove []corev1.Taint, newTaints *[]corev1.Taint) ([]error, bool) {
+	allErrs := []error{}
+	var removed bool
+	for _, taintToRemove := range taintsToRemove {
+		removed = false
+		if len(taintToRemove.Effect) > 0 {
+			*newTaints, removed = deleteTaint(*newTaints, &taintToRemove)
+		} else {
+			*newTaints, removed = deleteTaintsByKey(*newTaints, taintToRemove.Key)
+		}
+		if !removed {
+			allErrs = append(allErrs, fmt.Errorf("taint %q not found", taintToRemove.ToString()))
+		}
+	}
+	return allErrs, removed
+}
+
+// addTaints adds the newTaints list to existing ones and updates the newTaints List.
+// TODO: This needs a rewrite to take only the new values instead of appended newTaints list to be consistent.
+func addTaints(oldTaints []corev1.Taint, newTaints *[]corev1.Taint) bool {
+	for _, oldTaint := range oldTaints {
+		existsInNew := false
+		for _, taint := range *newTaints {
+			if taint.MatchTaint(&oldTaint) {
+				existsInNew = true
+				break
+			}
+		}
+		if !existsInNew {
+			*newTaints = append(*newTaints, oldTaint)
+		}
+	}
+	return len(oldTaints) != len(*newTaints)
+}
+
+// CheckIfTaintsAlreadyExists checks if the node already has taints that we want to add and returns a string with taint keys.
+func checkIfTaintsAlreadyExists(oldTaints []corev1.Taint, taints []corev1.Taint) string {
+	var existingTaintList = make([]string, 0)
+	for _, taint := range taints {
+		for _, oldTaint := range oldTaints {
+			if taint.Key == oldTaint.Key && taint.Effect == oldTaint.Effect {
+				existingTaintList = append(existingTaintList, taint.Key)
+			}
+		}
+	}
+	return strings.Join(existingTaintList, ",")
+}
+
+// DeleteTaintsByKey removes all the taints that have the same key to given taintKey
+func deleteTaintsByKey(taints []corev1.Taint, taintKey string) ([]corev1.Taint, bool) {
+	newTaints := []corev1.Taint{}
+	deleted := false
+	for i := range taints {
+		if taintKey == taints[i].Key {
+			deleted = true
+			continue
+		}
+		newTaints = append(newTaints, taints[i])
+	}
+	return newTaints, deleted
+}
+
+// DeleteTaint removes all the taints that have the same key and effect to given taintToDelete.
+func deleteTaint(taints []corev1.Taint, taintToDelete *corev1.Taint) ([]corev1.Taint, bool) {
+	newTaints := []corev1.Taint{}
+	deleted := false
+	for i := range taints {
+		if taintToDelete.MatchTaint(&taints[i]) {
+			deleted = true
+			continue
+		}
+		newTaints = append(newTaints, taints[i])
+	}
+	return newTaints, deleted
+}