helm/pkg/storage/storage.go

/*
Copyright 2016 The Kubernetes Authors All rights reserved.

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 storage // import "k8s.io/helm/pkg/storage"

import (
	rspb "k8s.io/helm/pkg/proto/hapi/release"
	"k8s.io/helm/pkg/storage/driver"
)

type Storage struct {
	driver.Driver
}

// Create creates a new storage entry holding the release.
// An error is returned if storage failed to store the release.
//
// TODO: Is marking the release as deployed the only task here?
// 		 What happens if an identical release already exists?
func (s *Storage) Create(rls *rspb.Release) error {
	return s.Driver.Create(rls)
}

// Update update the release in storage. An error is returned if the
// storage backend fails to update the release or if the release does not exist.
//
// TODO: Fetch most recent deployed release, if it exists, mark
// 		 as SUPERSEDED, then store both new and old.
func (s *Storage) Update(rls *rspb.Release) error {
	return s.Driver.Update(rls)
}

// Delete deletes the release from storage. An error is returned if the
// storage backend fails to delete the release or if the release does not exist.
//
// TODO: The release status should be modified to reflect the DELETED status.
func (s *Storage) Delete(key string) (*rspb.Release, error) {
	return s.Driver.Delete(key)
}

// ListReleases returns all releases from storage. An error is returned if the
// storage backend fails to retrieve the releases.
func (s *Storage) ListReleases() ([]*rspb.Release, error) {
	return s.Driver.List(func(_ *rspb.Release) bool { return true })
}

// ListDeleted returns all releases with Status == DELETED. An error is returned
// if the storage backend fails to retrieve the releases.
func (s *Storage) ListDeleted() ([]*rspb.Release, error) {
	return s.Driver.List(func(rls *rspb.Release) bool {
		return StatusFilter(rspb.Status_DELETED).Check(rls)
	})
}

// ListDeployed returns all releases with Status == DEPLOYED. An error is returned
// if the storage backend fails to retrieve the releases.
func (s *Storage) ListDeployed() ([]*rspb.Release, error) {
	return s.Driver.List(func(rls *rspb.Release) bool {
		return StatusFilter(rspb.Status_DEPLOYED).Check(rls)
	})
}

// ListFilterAll returns the set of releases satisfying satisfying the predicate
// (filter0 && filter1 && ... && filterN), i.e. a Release is included in the results
// if and only if all filters return true.
func (s *Storage) ListFilterAll(filters ...FilterFunc) ([]*rspb.Release, error) {
	return s.Driver.List(func(rls *rspb.Release) bool {
		return All(filters...).Check(rls)
	})
}

// ListFilterAny returns the set of releases satisfying satisfying the predicate
// (filter0 || filter1 || ... || filterN), i.e. a Release is included in the results
// if at least one of the filters returns true.
func (s *Storage) ListFilterAny(filters ...FilterFunc) ([]*rspb.Release, error) {
	return s.Driver.List(func(rls *rspb.Release) bool {
		return Any(filters...).Check(rls)
	})
}

func Init(d driver.Driver) *Storage {
	if d == nil {
		d = driver.NewMemory()
	}
	return &Storage{Driver: d}
}