backup.go

/*
Copyright 2017 Heptio Inc.

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 v1

import metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

// BackupSpec defines the specification for an Ark backup.
type BackupSpec struct {
	// IncludedNamespaces is a slice of namespace names to include objects
	// from. If empty, all namespaces are included.
	IncludedNamespaces []string `json:"includedNamespaces"`

	// ExcludedNamespaces contains a list of namespaces that are not
	// included in the backup.
	ExcludedNamespaces []string `json:"excludedNamespaces"`

	// IncludedResources is a slice of resource names to include
	// in the backup. If empty, all resources are included.
	IncludedResources []string `json:"includedResources"`

	// ExcludedResources is a slice of resource names that are not
	// included in the backup.
	ExcludedResources []string `json:"excludedResources"`

	// LabelSelector is a metav1.LabelSelector to filter with
	// when adding individual objects to the backup. If empty
	// or nil, all objects are included. Optional.
	LabelSelector *metav1.LabelSelector `json:"labelSelector"`

	// SnapshotVolumes specifies whether to take cloud snapshots
	// of any PV's referenced in the set of objects included
	// in the Backup.
	SnapshotVolumes *bool `json:"snapshotVolumes"`

	// TTL is a time.Duration-parseable string describing how long
	// the Backup should be retained for.
	TTL metav1.Duration `json:"ttl"`

	// IncludeClusterResources specifies whether cluster-scoped resources
	// should be included for consideration in the backup.
	IncludeClusterResources *bool `json:"includeClusterResources"`

	// Hooks represent custom behaviors that should be executed at different phases of the backup.
	Hooks BackupHooks `json:"hooks"`
}

// BackupHooks contains custom behaviors that should be executed at different phases of the backup.
type BackupHooks struct {
	// Resources are hooks that should be executed when backing up individual instances of a resource.
	Resources []BackupResourceHookSpec `json:"resources"`
}

// BackupResourceHookSpec defines one or more BackupResourceHooks that should be executed based on
// the rules defined for namespaces, resources, and label selector.
type BackupResourceHookSpec struct {
	// Name is the name of this hook.
	Name string `json:"name"`
	// IncludedNamespaces specifies the namespaces to which this hook spec applies. If empty, it applies
	// to all namespaces.
	IncludedNamespaces []string `json:"includedNamespaces"`
	// ExcludedNamespaces specifies the namespaces to which this hook spec does not apply.
	ExcludedNamespaces []string `json:"excludedNamespaces"`
	// IncludedResources specifies the resources to which this hook spec applies. If empty, it applies
	// to all resources.
	IncludedResources []string `json:"includedResources"`
	// ExcludedResources specifies the resources to which this hook spec does not apply.
	ExcludedResources []string `json:"excludedResources"`
	// LabelSelector, if specified, filters the resources to which this hook spec applies.
	LabelSelector *metav1.LabelSelector `json:"labelSelector"`
	// Hooks is a list of BackupResourceHooks to execute.
	Hooks []BackupResourceHook `json:"hooks"`
}

// BackupResourceHook defines a hook for a resource.
type BackupResourceHook struct {
	// Exec defines an exec hook.
	Exec *ExecHook `json:"exec"`
}

// ExecHook is a hook that uses the pod exec API to execute a command in a container in a pod.
type ExecHook struct {
	// Container is the container in the pod where the command should be executed. If not specified,
	// the pod's first container is used.
	Container string `json:"container"`
	// Command is the command and arguments to execute.
	Command []string `json:"command"`
	// OnError specifies how Ark should behave if it encounters an error executing this hook.
	OnError HookErrorMode `json:"onError"`
	// Timeout defines the maximum amount of time Ark should wait for the hook to complete before
	// considering the execution a failure.
	Timeout metav1.Duration `json:"timeout"`
}

// HookErrorMode defines how Ark should treat an error from a hook.
type HookErrorMode string

const (
	// HookErrorModeContinue means that an error from a hook is acceptable, and the backup can
	// proceed.
	HookErrorModeContinue HookErrorMode = "Continue"
	// HookErrorModeFail means that an error from a hook is problematic, and the backup should be in
	// error.
	HookErrorModeFail HookErrorMode = "Fail"
)

// BackupPhase is a string representation of the lifecycle phase
// of an Ark backup.
type BackupPhase string

const (
	// BackupPhaseNew means the backup has been created but not
	// yet processed by the BackupController.
	BackupPhaseNew BackupPhase = "New"

	// BackupPhaseFailedValidation means the backup has failed
	// the controller's validations and therefore will not run.
	BackupPhaseFailedValidation BackupPhase = "FailedValidation"

	// BackupPhaseInProgress means the backup is currently executing.
	BackupPhaseInProgress BackupPhase = "InProgress"

	// BackupPhaseCompleted means the backup has run successfully without
	// errors.
	BackupPhaseCompleted BackupPhase = "Completed"

	// BackupPhaseFailed mean the backup ran but encountered an error that
	// prevented it from completing successfully.
	BackupPhaseFailed BackupPhase = "Failed"
)

// BackupStatus captures the current status of an Ark backup.
type BackupStatus struct {
	// Version is the backup format version.
	Version int `json:"version"`

	// Expiration is when this Backup is eligible for garbage-collection.
	Expiration metav1.Time `json:"expiration"`

	// Phase is the current state of the Backup.
	Phase BackupPhase `json:"phase"`

	// VolumeBackups is a map of PersistentVolume names to
	// information about the backed-up volume in the cloud
	// provider API.
	VolumeBackups map[string]*VolumeBackupInfo `json:"volumeBackups"`

	// ValidationErrors is a slice of all validation errors (if
	// applicable).
	ValidationErrors []string `json:"validationErrors"`
}

// VolumeBackupInfo captures the required information about
// a PersistentVolume at backup time to be able to restore
// it later.
type VolumeBackupInfo struct {
	// SnapshotID is the ID of the snapshot taken in the cloud
	// provider API of this volume.
	SnapshotID string `json:"snapshotID"`

	// Type is the type of the disk/volume in the cloud provider
	// API.
	Type string `json:"type"`

	// AvailabilityZone is the where the volume is provisioned
	// in the cloud provider.
	AvailabilityZone string `json:"availabilityZone,omitempty"`

	// Iops is the optional value of provisioned IOPS for the
	// disk/volume in the cloud provider API.
	Iops *int64 `json:"iops,omitempty"`
}

// +genclient
// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

// Backup is an Ark resource that respresents the capture of Kubernetes
// cluster state at a point in time (API objects and associated volume state).
type Backup struct {
	metav1.TypeMeta   `json:",inline"`
	metav1.ObjectMeta `json:"metadata"`

	Spec   BackupSpec   `json:"spec"`
	Status BackupStatus `json:"status,omitempty"`
}

// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

// BackupList is a list of Backups.
type BackupList struct {
	metav1.TypeMeta `json:",inline"`
	metav1.ListMeta `json:"metadata"`
	Items           []Backup `json:"items"`
}