easykv

README

easyKV

easyKV is based on the backends of confd. easyKV provides a very simple interface to work with some key-value stores. The goal of easyKV is to abstract these 2 common operations for multiple backends:

• recursively query the kv-store for key-value pairs.
• watch a key-prefix for changes.

Interface

A storage backend in easyKV should implement (fully or partially) this interface:

type ReadWatcher interface {
	GetValues(keys []string) (map[string]string, error)
	WatchPrefix(ctx context.Context, prefix string, opts ...WatchOption) (uint64, error)
	Close()
}

Compatibility matrix

Calls	Consul	Etcdv2	Etcdv3	env	file	redis	vault	zookeeper	nats kv
GetValues	X	X	X	X	X	X	X	X	X
WatchPrefix	X	X	X		X			X	X
Close	X	X	X	X	X	X	X	X	X

Documentation

Index

• Variables
• type ReadWatcher
• type WatchOption
  • func WithKeys(keys []string) WatchOption
  • func WithWaitIndex(waitIndex uint64) WatchOption
• type WatchOptions

Variables

var ErrWatchCanceled = errors.New("watcher error: watcher canceled")

ErrWatchCanceled is returned if the watcher is canceled.

var ErrWatchNotSupported = errors.New("this backend doesn't support watches - use polling instead")

ErrWatchNotSupported is returned if the backend has no watch support and the WatchPrefix method is called.

Types

type ReadWatcher

type ReadWatcher interface {
	GetValues(keys []string) (map[string]string, error)
	WatchPrefix(ctx context.Context, prefix string, opts ...WatchOption) (uint64, error)
	Close()
}

A ReadWatcher - can get values and watch a prefix for changes

type WatchOption

type WatchOption func(*WatchOptions)

WatchOption configures the WatchPrefix operation

func WithKeys

func WithKeys(keys []string) WatchOption

WithKeys reduces the scope of keys that can trigger updates to keys (not an exact match)

func WithWaitIndex

func WithWaitIndex(waitIndex uint64) WatchOption

WithWaitIndex sets the WaitIndex of the watcher

type WatchOptions

type WatchOptions struct {
	WaitIndex uint64
	Keys      []string
}

WatchOptions represents options for watch operations