backend

Documentation

Overview

Copyright 2015 Gravitational, 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.

backend package allows for pluggable back-ends for secrets storage. To implement a new storage back-end you have to supply an object which:

• implements backend.Backend interface
• implements backend.NewFunc function

Index

• Constants
• func AnyTTL(clock clockwork.Clock, times ...time.Time) time.Duration
• func TTL(clock clockwork.Clock, t time.Time) time.Duration
• func ValidateLockTTL(ttl time.Duration) error
• type Backend
• type Config
• type Item
• type ItemsGetter
• type JSONCodec
  • func (c *JSONCodec) CreateJSONVal(path []string, key string, val interface{}, ttl time.Duration) error
  • func (c *JSONCodec) GetJSONVal(path []string, key string, val interface{}) error
  • func (c *JSONCodec) UpsertJSONVal(path []string, key string, val interface{}, ttl time.Duration) error
• type NameFunc
• type NewFunc
• type Params
  • func (p Params) GetString(key string) string

Constants

const (
	Forever         time.Duration = 0
	MaxLockDuration time.Duration = time.Minute
)

Forever means that object TTL will not expire unless deleted

Functions

func AnyTTL

func AnyTTL(clock clockwork.Clock, times ...time.Time) time.Duration

AnyTTL returns TTL if any of the suplied times pass expiry time otherwise returns forever

func TTL

func TTL(clock clockwork.Clock, t time.Time) time.Duration

TTL converts time to TTL from current time supplied by provider, if t is zero, returns forever

func ValidateLockTTL

func ValidateLockTTL(ttl time.Duration) error

ValidateLockTTL helper allows all backends to validate lock TTL parameter

Types

type Backend

type Backend interface {
	// GetKeys returns a list of keys for a given path
	GetKeys(bucket []string) ([]string, error)
	// CreateVal creates value with a given TTL and key in the bucket
	// if the value already exists, it must return trace.AlreadyExistsError
	CreateVal(bucket []string, key string, val []byte, ttl time.Duration) error
	// UpsertVal updates or inserts value with a given TTL into a bucket
	// ForeverTTL for no TTL
	UpsertVal(bucket []string, key string, val []byte, ttl time.Duration) error
	// GetVal return a value for a given key in the bucket
	GetVal(path []string, key string) ([]byte, error)
	// CompareAndSwapVal compares and swaps values in atomic operation,
	// succeeds if prevVal matches the value stored in the database,
	// requires prevVal as a non-empty value. Returns trace.CompareFailed
	// in case if value did not match.
	CompareAndSwapVal(bucket []string, key string, val []byte, prevVal []byte, ttl time.Duration) error
	// DeleteKey deletes a key in a bucket
	DeleteKey(bucket []string, key string) error
	// DeleteBucket deletes the bucket by a given path
	DeleteBucket(path []string, bkt string) error
	// AcquireLock grabs a lock that will be released automatically in TTL
	AcquireLock(token string, ttl time.Duration) error
	// ReleaseLock forces lock release before TTL
	ReleaseLock(token string) error
	// Close releases the resources taken up by this backend
	Close() error
	// Clock returns clock used by this backend
	Clock() clockwork.Clock
}

Backend implements abstraction over local or remote storage backend

Storage is modeled after BoltDB:

• bucket is a slice []string{"a", "b"}
• buckets contain key value pairs

type Config

type Config struct {
	// Type can be "bolt" or "etcd" or "dynamodb"
	Type string `yaml:"type,omitempty"`

	// Params is a generic key/value property bag which allows arbitrary
	// falues to be passed to backend
	Params Params `yaml:",inline"`
}

Config is used for 'storage' config section. It's a combination of values for various backends: 'boltdb', 'etcd', 'filesystem' and 'dynamodb'

type Item

type Item struct {
	// Key is an item key
	Key string
	// Value is an item value
	Value []byte
}

Item is a pair of key and value

type ItemsGetter

type ItemsGetter interface {
	// GetItems returns a list of items - key value pairs
	GetItems(bucket []string) ([]Item, error)
}

ItemsGetter is an interface that allows gettings all items in the bucket at once

type JSONCodec

type JSONCodec struct {
	Backend
}

func (*JSONCodec) CreateJSONVal

func (c *JSONCodec) CreateJSONVal(path []string, key string, val interface{}, ttl time.Duration) error

func (*JSONCodec) GetJSONVal

func (c *JSONCodec) GetJSONVal(path []string, key string, val interface{}) error

func (*JSONCodec) UpsertJSONVal

func (c *JSONCodec) UpsertJSONVal(path []string, key string, val interface{}, ttl time.Duration) error

type NameFunc

type NameFunc func() string

NameFunc type defines a function type which every backend must implement to return its name

type NewFunc

type NewFunc func(Params) (Backend, error)

NewFunc type defines a function type which every backend must implement to instantiate itself

type Params

type Params map[string]interface{}

backend.Params type defines a flexible unified back-end configuration API. It is just a map of key/value pairs which gets populated by `storage` section in Teleport YAML config.

func (Params) GetString

func (p Params) GetString(key string) string

GetString returns a string value stored in Params map, or an empty string if nothing is found