func validateIngressRuleValue(ingressRule *extensions.IngressRuleValue, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	if ingressRule.HTTP != nil {
		allErrs = append(allErrs, validateHTTPIngressRuleValue(ingressRule.HTTP, fldPath.Child("http"))...)
	}
	return allErrs
}

func ValidateJobSpec(spec *extensions.JobSpec, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}

	if spec.Parallelism != nil {
		allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(*spec.Parallelism), fldPath.Child("parallelism"))...)
	}
	if spec.Completions != nil {
		allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(*spec.Completions), fldPath.Child("completions"))...)
	}
	if spec.ActiveDeadlineSeconds != nil {
		allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(*spec.ActiveDeadlineSeconds), fldPath.Child("activeDeadlineSeconds"))...)
	}
	if spec.Selector == nil {
		allErrs = append(allErrs, field.Required(fldPath.Child("selector"), ""))
	} else {
		allErrs = append(allErrs, ValidateLabelSelector(spec.Selector, fldPath.Child("selector"))...)
	}

	if selector, err := extensions.LabelSelectorAsSelector(spec.Selector); err == nil {
		labels := labels.Set(spec.Template.Labels)
		if !selector.Matches(labels) {
			allErrs = append(allErrs, field.Invalid(fldPath.Child("template", "metadata", "labels"), spec.Template.Labels, "`selector` does not match template `labels`"))
		}
	}

	allErrs = append(allErrs, apivalidation.ValidatePodTemplateSpec(&spec.Template, fldPath.Child("template"))...)
	if spec.Template.Spec.RestartPolicy != api.RestartPolicyOnFailure &&
		spec.Template.Spec.RestartPolicy != api.RestartPolicyNever {
		allErrs = append(allErrs, field.NotSupported(fldPath.Child("template", "spec", "restartPolicy"),
			spec.Template.Spec.RestartPolicy, []string{string(api.RestartPolicyOnFailure), string(api.RestartPolicyNever)}))
	}
	return allErrs
}

func ValidateLabelSelector(ps *extensions.LabelSelector, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	if ps == nil {
		return allErrs
	}
	allErrs = append(allErrs, apivalidation.ValidateLabels(ps.MatchLabels, fldPath.Child("matchLabels"))...)
	for i, expr := range ps.MatchExpressions {
		allErrs = append(allErrs, ValidateLabelSelectorRequirement(expr, fldPath.Child("matchExpressions").Index(i))...)
	}
	return allErrs
}

func ValidateSelfSubjectAccessReviewSpec(spec authorizationapi.SelfSubjectAccessReviewSpec, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	if spec.ResourceAttributes != nil && spec.NonResourceAttributes != nil {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("nonResourceAttributes"), spec.NonResourceAttributes, `cannot be specified in combination with resourceAttributes`))
	}
	if spec.ResourceAttributes == nil && spec.NonResourceAttributes == nil {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("resourceAttributes"), spec.NonResourceAttributes, `exactly one of nonResourceAttributes or resourceAttributes must be specified`))
	}

	return allErrs
}

func ValidateRollingUpdateDaemonSet(rollingUpdate *extensions.RollingUpdateDaemonSet, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	allErrs = append(allErrs, ValidatePositiveIntOrPercent(rollingUpdate.MaxUnavailable, fldPath.Child("maxUnavailable"))...)
	if getIntOrPercentValue(rollingUpdate.MaxUnavailable) == 0 {
		// MaxUnavailable cannot be 0.
		allErrs = append(allErrs, field.Invalid(fldPath.Child("maxUnavailable"), rollingUpdate.MaxUnavailable, "cannot be 0"))
	}
	// Validate that MaxUnavailable is not more than 100%.
	allErrs = append(allErrs, IsNotMoreThan100Percent(rollingUpdate.MaxUnavailable, fldPath.Child("maxUnavailable"))...)
	allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(rollingUpdate.MinReadySeconds), fldPath.Child("minReadySeconds"))...)
	return allErrs
}

func ValidateDeploymentStrategy(strategy *extensions.DeploymentStrategy, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	if strategy.RollingUpdate == nil {
		return allErrs
	}
	switch strategy.Type {
	case extensions.RecreateDeploymentStrategyType:
		allErrs = append(allErrs, field.Forbidden(fldPath.Child("rollingUpdate"), "may not be specified when strategy `type` is '"+string(extensions.RecreateDeploymentStrategyType+"'")))
	case extensions.RollingUpdateDeploymentStrategyType:
		allErrs = append(allErrs, ValidateRollingUpdateDeployment(strategy.RollingUpdate, fldPath.Child("rollingUpdate"))...)
	}
	return allErrs
}

// ValidateIngressSpec tests if required fields in the IngressSpec are set.
func ValidateIngressSpec(spec *extensions.IngressSpec, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	// TODO: Is a default backend mandatory?
	if spec.Backend != nil {
		allErrs = append(allErrs, validateIngressBackend(spec.Backend, fldPath.Child("backend"))...)
	} else if len(spec.Rules) == 0 {
		allErrs = append(allErrs, field.Invalid(fldPath, spec.Rules, "either `backend` or `rules` must be specified"))
	}
	if len(spec.Rules) > 0 {
		allErrs = append(allErrs, validateIngressRules(spec.Rules, fldPath.Child("rules"))...)
	}
	return allErrs
}

// ValidateDaemonSetTemplateUpdate tests that certain fields in the daemon set's pod template are not updated.
func ValidateDaemonSetTemplateUpdate(podTemplate, oldPodTemplate api.PodTemplateSpec, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	podSpec := podTemplate.Spec
	// podTemplate.Spec is not a pointer, so we can modify NodeSelector and NodeName directly.
	podSpec.NodeSelector = oldPodTemplate.Spec.NodeSelector
	podSpec.NodeName = oldPodTemplate.Spec.NodeName
	// In particular, we do not allow updates to container images at this point.
	if !api.Semantic.DeepEqual(oldPodTemplate.Spec, podSpec) {
		// TODO: Pinpoint the specific field that causes the invalid error after we have strategic merge diff
		allErrs = append(allErrs, field.Forbidden(fldPath.Child("spec"), "daemonSet updates may not change fields other than `nodeSelector`"))
	}
	return allErrs
}

func validateHTTPIngressRuleValue(httpIngressRuleValue *extensions.HTTPIngressRuleValue, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	if len(httpIngressRuleValue.Paths) == 0 {
		allErrs = append(allErrs, field.Required(fldPath.Child("paths"), ""))
	}
	for i, rule := range httpIngressRuleValue.Paths {
		if len(rule.Path) > 0 {
			if !strings.HasPrefix(rule.Path, "/") {
				allErrs = append(allErrs, field.Invalid(fldPath.Child("paths").Index(i).Child("path"), rule.Path, "must be an absolute path"))
			}
			// TODO: More draconian path regex validation.
			// Path must be a valid regex. This is the basic requirement.
			// In addition to this any characters not allowed in a path per
			// RFC 3986 section-3.3 cannot appear as a literal in the regex.
			// Consider the example: http://host/valid?#bar, everything after
			// the last '/' is a valid regex that matches valid#bar, which
			// isn't a valid path, because the path terminates at the first ?
			// or #. A more sophisticated form of validation would detect that
			// the user is confusing url regexes with path regexes.
			_, err := regexp.CompilePOSIX(rule.Path)
			if err != nil {
				allErrs = append(allErrs, field.Invalid(fldPath.Child("paths").Index(i).Child("path"), rule.Path, "must be a valid regex"))
			}
		}
		allErrs = append(allErrs, validateIngressBackend(&rule.Backend, fldPath.Child("backend"))...)
	}
	return allErrs
}

// validateIngressBackend tests if a given backend is valid.
func validateIngressBackend(backend *extensions.IngressBackend, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}

	// All backends must reference a single local service by name, and a single service port by name or number.
	if len(backend.ServiceName) == 0 {
		return append(allErrs, field.Required(fldPath.Child("serviceName"), ""))
	} else if ok, errMsg := apivalidation.ValidateServiceName(backend.ServiceName, false); !ok {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("serviceName"), backend.ServiceName, errMsg))
	}
	if backend.ServicePort.Type == intstr.String {
		if !validation.IsDNS1123Label(backend.ServicePort.StrVal) {
			allErrs = append(allErrs, field.Invalid(fldPath.Child("servicePort"), backend.ServicePort.StrVal, apivalidation.DNS1123LabelErrorMsg))
		}
		if !validation.IsValidPortName(backend.ServicePort.StrVal) {
			allErrs = append(allErrs, field.Invalid(fldPath.Child("servicePort"), backend.ServicePort.StrVal, apivalidation.PortNameErrorMsg))
		}
	} else if !validation.IsValidPortNum(backend.ServicePort.IntValue()) {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("servicePort"), backend.ServicePort, apivalidation.PortRangeErrorMsg))
	}
	return allErrs
}

// ValidateDaemonSetSpec tests if required fields in the DaemonSetSpec are set.
func ValidateDaemonSetSpec(spec *extensions.DaemonSetSpec, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}

	allErrs = append(allErrs, ValidateLabelSelector(spec.Selector, fldPath.Child("selector"))...)

	selector, err := extensions.LabelSelectorAsSelector(spec.Selector)
	if err == nil && !selector.Matches(labels.Set(spec.Template.Labels)) {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("template", "metadata", "labels"), spec.Template.Labels, "`selector` does not match template `labels`"))
	}

	allErrs = append(allErrs, apivalidation.ValidatePodTemplateSpec(&spec.Template, fldPath.Child("template"))...)
	// Daemons typically run on more than one node, so mark Read-Write persistent disks as invalid.
	allErrs = append(allErrs, apivalidation.ValidateReadOnlyPersistentDisks(spec.Template.Spec.Volumes, fldPath.Child("template", "spec", "volumes"))...)
	// RestartPolicy has already been first-order validated as per ValidatePodTemplateSpec().
	if spec.Template.Spec.RestartPolicy != api.RestartPolicyAlways {
		allErrs = append(allErrs, field.NotSupported(fldPath.Child("template", "spec", "restartPolicy"), spec.Template.Spec.RestartPolicy, []string{string(api.RestartPolicyAlways)}))
	}

	allErrs = append(allErrs, ValidateDaemonSetUpdateStrategy(&spec.UpdateStrategy, fldPath.Child("updateStrategy"))...)

	return allErrs
}

// Validates the given template and ensures that it is in accordance with the desired selector and replicas.
func ValidatePodTemplateSpecForReplicaSet(template *api.PodTemplateSpec, selector labels.Selector, replicas int, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	if template == nil {
		allErrs = append(allErrs, field.Required(fldPath, ""))
	} else {
		if !selector.Empty() {
			// Verify that the ReplicaSet selector matches the labels in template.
			labels := labels.Set(template.Labels)
			if !selector.Matches(labels) {
				allErrs = append(allErrs, field.Invalid(fldPath.Child("metadata", "labels"), template.Labels, "`selector` does not match template `labels`"))
			}
		}
		allErrs = append(allErrs, apivalidation.ValidatePodTemplateSpec(template, fldPath)...)
		if replicas > 1 {
			allErrs = append(allErrs, apivalidation.ValidateReadOnlyPersistentDisks(template.Spec.Volumes, fldPath.Child("spec", "volumes"))...)
		}
		// RestartPolicy has already been first-order validated as per ValidatePodTemplateSpec().
		if template.Spec.RestartPolicy != api.RestartPolicyAlways {
			allErrs = append(allErrs, field.NotSupported(fldPath.Child("spec", "restartPolicy"), template.Spec.RestartPolicy, []string{string(api.RestartPolicyAlways)}))
		}
	}
	return allErrs
}

func ValidateLabelSelectorRequirement(sr extensions.LabelSelectorRequirement, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	switch sr.Operator {
	case extensions.LabelSelectorOpIn, extensions.LabelSelectorOpNotIn:
		if len(sr.Values) == 0 {
			allErrs = append(allErrs, field.Required(fldPath.Child("values"), "must be specified when `operator` is 'In' or 'NotIn'"))
		}
	case extensions.LabelSelectorOpExists, extensions.LabelSelectorOpDoesNotExist:
		if len(sr.Values) > 0 {
			allErrs = append(allErrs, field.Forbidden(fldPath.Child("values"), "may not be specified when `operator` is 'Exists' or 'DoesNotExist'"))
		}
	default:
		allErrs = append(allErrs, field.Invalid(fldPath.Child("operator"), sr.Operator, "not a valid selector operator"))
	}
	allErrs = append(allErrs, apivalidation.ValidateLabelName(sr.Key, fldPath.Child("key"))...)
	return allErrs
}

// Validates given deployment spec.
func ValidateDeploymentSpec(spec *extensions.DeploymentSpec, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	allErrs = append(allErrs, apivalidation.ValidateNonEmptySelector(spec.Selector, fldPath.Child("selector"))...)
	allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(spec.Replicas), fldPath.Child("replicas"))...)
	allErrs = append(allErrs, apivalidation.ValidatePodTemplateSpecForRC(&spec.Template, spec.Selector, spec.Replicas, fldPath.Child("template"))...)
	allErrs = append(allErrs, ValidateDeploymentStrategy(&spec.Strategy, fldPath.Child("strategy"))...)
	if spec.RevisionHistoryLimit != nil {
		// zero is a valid RevisionHistoryLimit
		allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(*spec.RevisionHistoryLimit), fldPath.Child("revisionHistoryLimit"))...)
	}
	// empty string is a valid UniqueLabelKey
	if len(spec.UniqueLabelKey) > 0 {
		allErrs = append(allErrs, apivalidation.ValidateLabelName(spec.UniqueLabelKey, fldPath.Child("uniqueLabel"))...)
	}
	if spec.RollbackTo != nil {
		allErrs = append(allErrs, ValidateRollback(spec.RollbackTo, fldPath.Child("rollback"))...)
	}
	return allErrs
}

func ValidateDaemonSetUpdateStrategy(strategy *extensions.DaemonSetUpdateStrategy, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	// Only rolling update is supported at this time.
	if strategy.Type != extensions.RollingUpdateDaemonSetStrategyType {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("type"), strategy.Type, "RollingUpdate is the only supported type"))
	}
	// Make sure RollingUpdate field isn't nil.
	if strategy.RollingUpdate == nil {
		allErrs = append(allErrs, field.Required(fldPath.Child("rollingUpdate"), ""))
		return allErrs
	}
	allErrs = append(allErrs, ValidateRollingUpdateDaemonSet(strategy.RollingUpdate, fldPath.Child("rollingUpdate"))...)
	return allErrs
}

// ValidateReplicaSetSpec tests if required fields in the ReplicaSet spec are set.
func ValidateReplicaSetSpec(spec *extensions.ReplicaSetSpec, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}

	allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(spec.Replicas), fldPath.Child("replicas"))...)

	if spec.Selector == nil {
		allErrs = append(allErrs, field.Required(fldPath.Child("selector"), ""))
	} else {
		allErrs = append(allErrs, ValidateLabelSelector(spec.Selector, fldPath.Child("selector"))...)
		if len(spec.Selector.MatchLabels)+len(spec.Selector.MatchExpressions) == 0 {
			allErrs = append(allErrs, field.Invalid(fldPath.Child("selector"), spec.Selector, "empty selector is not valid for deployment."))
		}
	}

	selector, err := extensions.LabelSelectorAsSelector(spec.Selector)
	if err != nil {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("selector"), spec.Selector, "failed to convert LabelSelector to Selector."))
	} else {
		allErrs = append(allErrs, ValidatePodTemplateSpecForReplicaSet(spec.Template, selector, spec.Replicas, fldPath.Child("template"))...)
	}
	return allErrs
}

func validateIngressRules(IngressRules []extensions.IngressRule, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	if len(IngressRules) == 0 {
		return append(allErrs, field.Required(fldPath, ""))
	}
	for i, ih := range IngressRules {
		if len(ih.Host) > 0 {
			// TODO: Ports and ips are allowed in the host part of a url
			// according to RFC 3986, consider allowing them.
			if valid, errMsg := apivalidation.NameIsDNSSubdomain(ih.Host, false); !valid {
				allErrs = append(allErrs, field.Invalid(fldPath.Index(i).Child("host"), ih.Host, errMsg))
			}
			if isIP := (net.ParseIP(ih.Host) != nil); isIP {
				allErrs = append(allErrs, field.Invalid(fldPath.Index(i).Child("host"), ih.Host, "must be a DNS name, not an IP address"))
			}
		}
		allErrs = append(allErrs, validateIngressRuleValue(&ih.IngressRuleValue, fldPath.Index(0))...)
	}
	return allErrs
}

// validateDaemonSetStatus validates a DaemonSetStatus
func validateDaemonSetStatus(status *extensions.DaemonSetStatus, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(status.CurrentNumberScheduled), fldPath.Child("currentNumberScheduled"))...)
	allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(status.NumberMisscheduled), fldPath.Child("numberMisscheduled"))...)
	allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(status.DesiredNumberScheduled), fldPath.Child("desiredNumberScheduled"))...)
	return allErrs
}

func validateHorizontalPodAutoscalerSpec(autoscaler extensions.HorizontalPodAutoscalerSpec, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	if autoscaler.MinReplicas != nil && *autoscaler.MinReplicas < 1 {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("minReplicas"), *autoscaler.MinReplicas, "must be greater than 0"))
	}
	if autoscaler.MaxReplicas < 1 {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("maxReplicas"), autoscaler.MaxReplicas, "must be greater than 0"))
	}
	if autoscaler.MinReplicas != nil && autoscaler.MaxReplicas < *autoscaler.MinReplicas {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("maxReplicas"), autoscaler.MaxReplicas, "must be greater than or equal to `minReplicas`"))
	}
	if autoscaler.CPUUtilization != nil && autoscaler.CPUUtilization.TargetPercentage < 1 {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("cpuUtilization", "targetPercentage"), autoscaler.CPUUtilization.TargetPercentage, "must be greater than 0"))
	}
	if refErrs := ValidateSubresourceReference(autoscaler.ScaleRef, fldPath.Child("scaleRef")); len(refErrs) > 0 {
		allErrs = append(allErrs, refErrs...)
	} else if autoscaler.ScaleRef.Subresource != "scale" {
		allErrs = append(allErrs, field.NotSupported(fldPath.Child("scaleRef", "subresource"), autoscaler.ScaleRef.Subresource, []string{"scale"}))
	}
	return allErrs
}

func ValidateSubresourceReference(ref extensions.SubresourceReference, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	if len(ref.Kind) == 0 {
		allErrs = append(allErrs, field.Required(fldPath.Child("kind"), ""))
	} else if ok, msg := apivalidation.IsValidPathSegmentName(ref.Kind); !ok {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("kind"), ref.Kind, msg))
	}

	if len(ref.Name) == 0 {
		allErrs = append(allErrs, field.Required(fldPath.Child("name"), ""))
	} else if ok, msg := apivalidation.IsValidPathSegmentName(ref.Name); !ok {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("name"), ref.Name, msg))
	}

	if len(ref.Subresource) == 0 {
		allErrs = append(allErrs, field.Required(fldPath.Child("subresource"), ""))
	} else if ok, msg := apivalidation.IsValidPathSegmentName(ref.Subresource); !ok {
		allErrs = append(allErrs, field.Invalid(fldPath.Child("subresource"), ref.Subresource, msg))
	}
	return allErrs
}