kops/upup/pkg/kutil/node_utils.go

/*
Copyright 2016 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 kutil

import (
	client "k8s.io/kubernetes/pkg/client/unversioned"
	"time"
	"k8s.io/kubernetes/pkg/api"
	"github.com/golang/glog"
	"k8s.io/kubernetes/pkg/util/wait"
	"k8s.io/kubernetes/pkg/fields"
)

const (
	// How often to Poll pods, nodes and claims.
	Poll = 2 * time.Second

	// How long to try single API calls (like 'get' or 'list'). Used to prevent
	// transient failures from failing tests.
	// TODO: client should not apply this timeout to Watch calls. Increased from 30s until that is fixed.
	SingleCallTimeout = 5 * time.Minute
)


// GetReadySchedulableNodesOrDie addresses the common use case of getting nodes you can do work on.
// 1) Needs to be schedulable.
// 2) Needs to be ready.
// If EITHER 1 or 2 is not true, most tests will want to ignore the node entirely.
func GetReadySchedulableNodesOrDie(c *client.Client) (nodes *api.NodeList) {
	nodes = waitListSchedulableNodesOrDie(c)
	// previous tests may have cause failures of some nodes. Let's skip
	// 'Not Ready' nodes, just in case (there is no need to fail the test).
	FilterNodes(nodes, func(node api.Node) bool {
		return isNodeSchedulable(&node)
	})
	return nodes
}

// waitListSchedulableNodesOrDie is a wrapper around listing nodes supporting retries.
func waitListSchedulableNodesOrDie(c *client.Client) *api.NodeList {
	var nodes *api.NodeList
	var err error
	if wait.PollImmediate(Poll, SingleCallTimeout, func() (bool, error) {
		nodes, err = c.Nodes().List(api.ListOptions{FieldSelector: fields.Set{
			"spec.unschedulable": "false",
		}.AsSelector()})
		return err == nil, nil
	}) != nil {
		ExpectNoError(err, "Timed out while listing nodes for e2e cluster.")
	}
	return nodes
}

// Node is schedulable if:
// 1) doesn't have "unschedulable" field set
// 2) it's Ready condition is set to true
// 3) doesn't have NetworkUnavailable condition set to true
func isNodeSchedulable(node *api.Node) bool {
	nodeReady := IsNodeConditionSetAsExpected(node, api.NodeReady, true)
	networkReady := IsNodeConditionUnset(node, api.NodeNetworkUnavailable) ||
		IsNodeConditionSetAsExpectedSilent(node, api.NodeNetworkUnavailable, false)
	return !node.Spec.Unschedulable && nodeReady && networkReady
}

func IsNodeConditionSetAsExpectedSilent(node *api.Node, conditionType api.NodeConditionType, wantTrue bool) bool {
	return isNodeConditionSetAsExpected(node, conditionType, wantTrue, true)
}

func IsNodeConditionUnset(node *api.Node, conditionType api.NodeConditionType) bool {
	for _, cond := range node.Status.Conditions {
		if cond.Type == conditionType {
			return false
		}
	}
	return true
}
func FilterNodes(nodeList *api.NodeList, fn func(node api.Node) bool) {
	var l []api.Node

	for _, node := range nodeList.Items {
		if fn(node) {
			l = append(l, node)
		}
	}
	nodeList.Items = l
}

// waitListSchedulableNodesOrDie is a wrapper around listing nodes supporting retries.
func waitListSchedulableNodesOrDie(c *client.Client) (*api.NodeList, error) {
	var nodes *api.NodeList
	var err error
	if wait.PollImmediate(Poll, SingleCallTimeout, func() (bool, error) {
		nodes, err = c.Nodes().List(api.ListOptions{FieldSelector: fields.Set{
			"spec.unschedulable": "false",
		}.AsSelector()})
		return nodes, err
	}) != nil {
		return nil, err
	}
	return nodes, nil
}

// WaitForNodeToBeReady returns whether node name is ready within timeout.
func WaitForNodeToBeReady(c *client.Client, name string, timeout time.Duration) bool {
	return WaitForNodeToBe(c, name, api.NodeReady, true, timeout)
}

// WaitForNodeToBeNotReady returns whether node name is not ready (i.e. the
// readiness condition is anything but ready, e.g false or unknown) within
// timeout.
func WaitForNodeToBeNotReady(c *client.Client, name string, timeout time.Duration) bool {
	return WaitForNodeToBe(c, name, api.NodeReady, false, timeout)
}

// WaitForNodeToBe returns whether node "name's" condition state matches wantTrue
// within timeout. If wantTrue is true, it will ensure the node condition status
// is ConditionTrue; if it's false, it ensures the node condition is in any state
// other than ConditionTrue (e.g. not true or unknown).
func WaitForNodeToBe(c *client.Client, name string, conditionType api.NodeConditionType, wantTrue bool, timeout time.Duration) bool {
	glog.V(4).Infof("Waiting up to %v for node %s condition %s to be %t", timeout, name, conditionType, wantTrue)
	for start := time.Now(); time.Since(start) < timeout; time.Sleep(Poll) {
		node, err := c.Nodes().Get(name)
		if err != nil {
			glog.V(4).Infof("Couldn't get node %s", name)
			continue
		}

		if IsNodeConditionSetAsExpected(node, conditionType, wantTrue) {
			return true
		}
	}
	glog.V(4).Infof("Node %s didn't reach desired %s condition status (%t) within %v", name, conditionType, wantTrue, timeout)
	return false
}

func IsNodeConditionSetAsExpected(node *api.Node, conditionType api.NodeConditionType, wantTrue bool) bool {
	return isNodeConditionSetAsExpected(node, conditionType, wantTrue, false)
}

func isNodeConditionSetAsExpected(node *api.Node, conditionType api.NodeConditionType, wantTrue, silent bool) bool {
	// Check the node readiness condition (logging all).
	for _, cond := range node.Status.Conditions {
		// Ensure that the condition type and the status matches as desired.
		if cond.Type == conditionType {
			if (cond.Status == api.ConditionTrue) == wantTrue {
				return true
			} else {
				if !silent {
					glog.V(4).Infof(
						"Condition %s of node %s is %v instead of %t. Reason: %v, message: %v",
						conditionType, node.Name, cond.Status == api.ConditionTrue, wantTrue, cond.Reason, cond.Message)
				}
				return false
			}
		}
	}
	if !silent {
		glog.V(4).Infof("Couldn't find condition %v on node %v", conditionType, node.Name)
	}
	return false
}