| /* |
| 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 autoscaling |
| |
| import ( |
| "k8s.io/apimachinery/pkg/api/resource" |
| metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" |
| api "k8s.io/kubernetes/pkg/apis/core" |
| ) |
| |
| // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object |
| |
| // Scale represents a scaling request for a resource. |
| type Scale struct { |
| metav1.TypeMeta |
| // Standard object metadata; More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#metadata. |
| // +optional |
| metav1.ObjectMeta |
| |
| // defines the behavior of the scale. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#spec-and-status. |
| // +optional |
| Spec ScaleSpec |
| |
| // current status of the scale. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#spec-and-status. Read-only. |
| // +optional |
| Status ScaleStatus |
| } |
| |
| // ScaleSpec describes the attributes of a scale subresource. |
| type ScaleSpec struct { |
| // desired number of instances for the scaled object. |
| // +optional |
| Replicas int32 |
| } |
| |
| // ScaleStatus represents the current status of a scale subresource. |
| type ScaleStatus struct { |
| // actual number of observed instances of the scaled object. |
| Replicas int32 |
| |
| // label query over pods that should match the replicas count. This is same |
| // as the label selector but in the string format to avoid introspection |
| // by clients. The string will be in the same format as the query-param syntax. |
| // More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#label-selectors |
| // +optional |
| Selector string |
| } |
| |
| // CrossVersionObjectReference contains enough information to let you identify the referred resource. |
| type CrossVersionObjectReference struct { |
| // Kind of the referent; More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#types-kinds" |
| Kind string |
| // Name of the referent; More info: http://kubernetes.io/docs/user-guide/identifiers#names |
| Name string |
| // API version of the referent |
| // +optional |
| APIVersion string |
| } |
| |
| // HorizontalPodAutoscalerSpec describes the desired functionality of the HorizontalPodAutoscaler. |
| type HorizontalPodAutoscalerSpec struct { |
| // ScaleTargetRef points to the target resource to scale, and is used to the pods for which metrics |
| // should be collected, as well as to actually change the replica count. |
| ScaleTargetRef CrossVersionObjectReference |
| // MinReplicas is the lower limit for the number of replicas to which the autoscaler can scale down. |
| // It defaults to 1 pod. |
| // +optional |
| MinReplicas *int32 |
| // MaxReplicas is the upper limit for the number of replicas to which the autoscaler can scale up. |
| // It cannot be less that minReplicas. |
| MaxReplicas int32 |
| // Metrics contains the specifications for which to use to calculate the |
| // desired replica count (the maximum replica count across all metrics will |
| // be used). The desired replica count is calculated multiplying the |
| // ratio between the target value and the current value by the current |
| // number of pods. Ergo, metrics used must decrease as the pod count is |
| // increased, and vice-versa. See the individual metric source types for |
| // more information about how each type of metric must respond. |
| // +optional |
| Metrics []MetricSpec |
| } |
| |
| // MetricSourceType indicates the type of metric. |
| type MetricSourceType string |
| |
| var ( |
| // ObjectMetricSourceType is a metric describing a kubernetes object |
| // (for example, hits-per-second on an Ingress object). |
| ObjectMetricSourceType MetricSourceType = "Object" |
| // PodsMetricSourceType is a metric describing each pod in the current scale |
| // target (for example, transactions-processed-per-second). The values |
| // will be averaged together before being compared to the target value. |
| PodsMetricSourceType MetricSourceType = "Pods" |
| // ResourceMetricSourceType is a resource metric known to Kubernetes, as |
| // specified in requests and limits, describing each pod in the current |
| // scale target (e.g. CPU or memory). Such metrics are built in to |
| // Kubernetes, and have special scaling options on top of those available |
| // to normal per-pod metrics (the "pods" source). |
| ResourceMetricSourceType MetricSourceType = "Resource" |
| // ExternalMetricSourceType is a global metric that is not associated |
| // with any Kubernetes object. It allows autoscaling based on information |
| // coming from components running outside of cluster |
| // (for example length of queue in cloud messaging service, or |
| // QPS from loadbalancer running outside of cluster). |
| ExternalMetricSourceType MetricSourceType = "External" |
| ) |
| |
| // MetricSpec specifies how to scale based on a single metric |
| // (only `type` and one other matching field should be set at once). |
| type MetricSpec struct { |
| // Type is the type of metric source. It should be one of "Object", |
| // "Pods" or "Resource", each mapping to a matching field in the object. |
| Type MetricSourceType |
| |
| // Object refers to a metric describing a single kubernetes object |
| // (for example, hits-per-second on an Ingress object). |
| // +optional |
| Object *ObjectMetricSource |
| // Pods refers to a metric describing each pod in the current scale target |
| // (for example, transactions-processed-per-second). The values will be |
| // averaged together before being compared to the target value. |
| // +optional |
| Pods *PodsMetricSource |
| // Resource refers to a resource metric (such as those specified in |
| // requests and limits) known to Kubernetes describing each pod in the |
| // current scale target (e.g. CPU or memory). Such metrics are built in to |
| // Kubernetes, and have special scaling options on top of those available |
| // to normal per-pod metrics using the "pods" source. |
| // +optional |
| Resource *ResourceMetricSource |
| // External refers to a global metric that is not associated |
| // with any Kubernetes object. It allows autoscaling based on information |
| // coming from components running outside of cluster |
| // (for example length of queue in cloud messaging service, or |
| // QPS from loadbalancer running outside of cluster). |
| // +optional |
| External *ExternalMetricSource |
| } |
| |
| // ObjectMetricSource indicates how to scale on a metric describing a |
| // kubernetes object (for example, hits-per-second on an Ingress object). |
| type ObjectMetricSource struct { |
| DescribedObject CrossVersionObjectReference |
| Target MetricTarget |
| Metric MetricIdentifier |
| } |
| |
| // PodsMetricSource indicates how to scale on a metric describing each pod in |
| // the current scale target (for example, transactions-processed-per-second). |
| // The values will be averaged together before being compared to the target |
| // value. |
| type PodsMetricSource struct { |
| // metric identifies the target metric by name and selector |
| Metric MetricIdentifier |
| // target specifies the target value for the given metric |
| Target MetricTarget |
| } |
| |
| // ResourceMetricSource indicates how to scale on a resource metric known to |
| // Kubernetes, as specified in requests and limits, describing each pod in the |
| // current scale target (e.g. CPU or memory). The values will be averaged |
| // together before being compared to the target. Such metrics are built in to |
| // Kubernetes, and have special scaling options on top of those available to |
| // normal per-pod metrics using the "pods" source. Only one "target" type |
| // should be set. |
| type ResourceMetricSource struct { |
| // Name is the name of the resource in question. |
| Name api.ResourceName |
| // Target specifies the target value for the given metric |
| Target MetricTarget |
| } |
| |
| // ExternalMetricSource indicates how to scale on a metric not associated with |
| // any Kubernetes object (for example length of queue in cloud |
| // messaging service, or QPS from loadbalancer running outside of cluster). |
| type ExternalMetricSource struct { |
| // Metric identifies the target metric by name and selector |
| Metric MetricIdentifier |
| // Target specifies the target value for the given metric |
| Target MetricTarget |
| } |
| |
| // MetricIdentifier defines the name and optionally selector for a metric |
| type MetricIdentifier struct { |
| // Name is the name of the given metric |
| Name string |
| // Selector is the selector for the given metric |
| // it is the string-encoded form of a standard kubernetes label selector |
| // +optional |
| Selector *metav1.LabelSelector |
| } |
| |
| // MetricTarget defines the target value, average value, or average utilization of a specific metric |
| type MetricTarget struct { |
| // Type represents whether the metric type is Utilization, Value, or AverageValue |
| Type MetricTargetType |
| // Value is the target value of the metric (as a quantity). |
| Value *resource.Quantity |
| // TargetAverageValue is the target value of the average of the |
| // metric across all relevant pods (as a quantity) |
| AverageValue *resource.Quantity |
| |
| // AverageUtilization is the target value of the average of the |
| // resource metric across all relevant pods, represented as a percentage of |
| // the requested value of the resource for the pods. |
| // Currently only valid for Resource metric source type |
| AverageUtilization *int32 |
| } |
| |
| // MetricTargetType specifies the type of metric being targeted, and should be either |
| // "Value", "AverageValue", or "Utilization" |
| type MetricTargetType string |
| |
| var ( |
| UtilizationMetricType MetricTargetType = "Utilization" |
| ValueMetricType MetricTargetType = "Value" |
| AverageValueMetricType MetricTargetType = "AverageValue" |
| ) |
| |
| // HorizontalPodAutoscalerStatus describes the current status of a horizontal pod autoscaler. |
| type HorizontalPodAutoscalerStatus struct { |
| // ObservedGeneration is the most recent generation observed by this autoscaler. |
| // +optional |
| ObservedGeneration *int64 |
| |
| // LastScaleTime is the last time the HorizontalPodAutoscaler scaled the number of pods, |
| // used by the autoscaler to control how often the number of pods is changed. |
| // +optional |
| LastScaleTime *metav1.Time |
| |
| // CurrentReplicas is current number of replicas of pods managed by this autoscaler, |
| // as last seen by the autoscaler. |
| CurrentReplicas int32 |
| |
| // DesiredReplicas is the desired number of replicas of pods managed by this autoscaler, |
| // as last calculated by the autoscaler. |
| DesiredReplicas int32 |
| |
| // CurrentMetrics is the last read state of the metrics used by this autoscaler. |
| // +optional |
| CurrentMetrics []MetricStatus |
| |
| // Conditions is the set of conditions required for this autoscaler to scale its target, |
| // and indicates whether or not those conditions are met. |
| Conditions []HorizontalPodAutoscalerCondition |
| } |
| |
| // ConditionStatus indicates the status of a condition (true, false, or unknown). |
| type ConditionStatus string |
| |
| // These are valid condition statuses. "ConditionTrue" means a resource is in the condition; |
| // "ConditionFalse" means a resource is not in the condition; "ConditionUnknown" means kubernetes |
| // can't decide if a resource is in the condition or not. In the future, we could add other |
| // intermediate conditions, e.g. ConditionDegraded. |
| const ( |
| ConditionTrue ConditionStatus = "True" |
| ConditionFalse ConditionStatus = "False" |
| ConditionUnknown ConditionStatus = "Unknown" |
| ) |
| |
| // HorizontalPodAutoscalerConditionType are the valid conditions of |
| // a HorizontalPodAutoscaler. |
| type HorizontalPodAutoscalerConditionType string |
| |
| var ( |
| // ScalingActive indicates that the HPA controller is able to scale if necessary: |
| // it's correctly configured, can fetch the desired metrics, and isn't disabled. |
| ScalingActive HorizontalPodAutoscalerConditionType = "ScalingActive" |
| // AbleToScale indicates a lack of transient issues which prevent scaling from occurring, |
| // such as being in a backoff window, or being unable to access/update the target scale. |
| AbleToScale HorizontalPodAutoscalerConditionType = "AbleToScale" |
| // ScalingLimited indicates that the calculated scale based on metrics would be above or |
| // below the range for the HPA, and has thus been capped. |
| ScalingLimited HorizontalPodAutoscalerConditionType = "ScalingLimited" |
| ) |
| |
| // HorizontalPodAutoscalerCondition describes the state of |
| // a HorizontalPodAutoscaler at a certain point. |
| type HorizontalPodAutoscalerCondition struct { |
| // Type describes the current condition |
| Type HorizontalPodAutoscalerConditionType |
| // Status is the status of the condition (True, False, Unknown) |
| Status ConditionStatus |
| // LastTransitionTime is the last time the condition transitioned from |
| // one status to another |
| // +optional |
| LastTransitionTime metav1.Time |
| // Reason is the reason for the condition's last transition. |
| // +optional |
| Reason string |
| // Message is a human-readable explanation containing details about |
| // the transition |
| // +optional |
| Message string |
| } |
| |
| // MetricStatus describes the last-read state of a single metric. |
| type MetricStatus struct { |
| // Type is the type of metric source. It will be one of "Object", |
| // "Pods" or "Resource", each corresponds to a matching field in the object. |
| Type MetricSourceType |
| |
| // Object refers to a metric describing a single kubernetes object |
| // (for example, hits-per-second on an Ingress object). |
| // +optional |
| Object *ObjectMetricStatus |
| // Pods refers to a metric describing each pod in the current scale target |
| // (for example, transactions-processed-per-second). The values will be |
| // averaged together before being compared to the target value. |
| // +optional |
| Pods *PodsMetricStatus |
| // Resource refers to a resource metric (such as those specified in |
| // requests and limits) known to Kubernetes describing each pod in the |
| // current scale target (e.g. CPU or memory). Such metrics are built in to |
| // Kubernetes, and have special scaling options on top of those available |
| // to normal per-pod metrics using the "pods" source. |
| // +optional |
| Resource *ResourceMetricStatus |
| // External refers to a global metric that is not associated |
| // with any Kubernetes object. It allows autoscaling based on information |
| // coming from components running outside of cluster |
| // (for example length of queue in cloud messaging service, or |
| // QPS from loadbalancer running outside of cluster). |
| // +optional |
| External *ExternalMetricStatus |
| } |
| |
| // ObjectMetricStatus indicates the current value of a metric describing a |
| // kubernetes object (for example, hits-per-second on an Ingress object). |
| type ObjectMetricStatus struct { |
| Metric MetricIdentifier |
| Current MetricValueStatus |
| |
| DescribedObject CrossVersionObjectReference |
| } |
| |
| // PodsMetricStatus indicates the current value of a metric describing each pod in |
| // the current scale target (for example, transactions-processed-per-second). |
| type PodsMetricStatus struct { |
| Metric MetricIdentifier |
| Current MetricValueStatus |
| } |
| |
| // ResourceMetricStatus indicates the current value of a resource metric known to |
| // Kubernetes, as specified in requests and limits, describing each pod in the |
| // current scale target (e.g. CPU or memory). Such metrics are built in to |
| // Kubernetes, and have special scaling options on top of those available to |
| // normal per-pod metrics using the "pods" source. |
| type ResourceMetricStatus struct { |
| // Name is the name of the resource in question. |
| Name api.ResourceName |
| Current MetricValueStatus |
| } |
| |
| // ExternalMetricStatus indicates the current value of a global metric |
| // not associated with any Kubernetes object. |
| type ExternalMetricStatus struct { |
| Metric MetricIdentifier |
| Current MetricValueStatus |
| } |
| |
| type MetricValueStatus struct { |
| Value *resource.Quantity |
| AverageValue *resource.Quantity |
| AverageUtilization *int32 |
| } |
| |
| // +genclient |
| // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object |
| |
| // HorizontalPodAutoscaler is the configuration for a horizontal pod |
| // autoscaler, which automatically manages the replica count of any resource |
| // implementing the scale subresource based on the metrics specified. |
| type HorizontalPodAutoscaler struct { |
| metav1.TypeMeta |
| // Metadata is the standard object metadata. |
| // More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#metadata |
| // +optional |
| metav1.ObjectMeta |
| |
| // Spec is the specification for the behaviour of the autoscaler. |
| // More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#spec-and-status. |
| // +optional |
| Spec HorizontalPodAutoscalerSpec |
| |
| // Status is the current information about the autoscaler. |
| // +optional |
| Status HorizontalPodAutoscalerStatus |
| } |
| |
| // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object |
| |
| // HorizontalPodAutoscalerList is a list of horizontal pod autoscaler objects. |
| type HorizontalPodAutoscalerList struct { |
| metav1.TypeMeta |
| // Metadata is the standard list metadata. |
| // +optional |
| metav1.ListMeta |
| |
| // Items is the list of horizontal pod autoscaler objects. |
| Items []HorizontalPodAutoscaler |
| } |