db

Documentation

Index

• Variables
• func KeystoreLocation() string
• type StorageEngine
• type Store
  • func NewStore(se StorageEngine) (Store, error)
  • func Open() (Store, error)

Variables

var (
	// ErrNotFound is returned when the key supplied to a Get or Delete
	// method does not exist in the database.
	ErrNotFound = errors.New("db: key not found")

	// ErrBadValue is returned when the value supplied to the Put method is nil.
	ErrBadValue = errors.New("db: bad value")
)

Functions

func KeystoreLocation

func KeystoreLocation() string

KeystoreLocation returns the file path to store the DB for individual users. This will be ~/.hpe/store.db

Types

type StorageEngine

type StorageEngine int

StorageEngine defines the backend storage engine to be used This ostensibly allows different backends to be used. e.g. if we want to switch to a json based file

const (

	// SKV is Simple Key Value store from: github.com/rapidloop/skv
	SKV StorageEngine = iota
)

type Store

type Store interface {
	// Get an entry from the store. "value" must be a pointer-typed. If the key
	// is not present in the store, Get returns ErrNotFound.
	//
	//	type MyStruct struct {
	//	    Numbers []int
	//	}
	//	var val MyStruct
	//	if err := store.Get("key42", &val); err == store.ErrNotFound {
	//	    // "key42" not found
	//	} else if err != nil {
	//	    // an error occurred
	//	} else {
	//	    // ok
	//	}
	//
	// The value passed to Get() can be nil, in which case any value read from
	// the store is silently discarded.
	//
	//  if err := store.Get("key42", nil); err == nil {
	//      fmt.Println("entry is present")
	//  }
	Get(key string, value interface{}) error
	// Put an entry into the store. The passed value is gob-encoded and stored.
	// The key can be an empty string, but the value cannot be nil - if it is,
	// Put() returns ErrBadValue.
	//
	//	err := store.Put("key42", 156)
	//	err := store.Put("key42", "this is a string")
	//	m := map[string]int{
	//	    "harry": 100,
	//	    "emma":  101,
	//	}
	//	err := store.Put("key43", m)
	Put(key string, value interface{}) error
	// Delete the entry with the given key. If no such key is present in the store,
	// it returns ErrNotFound.
	//
	//	store.Delete("key42")
	Delete(key string) error
	// Close closes the key-value store file.
	Close() error
}

Store is the interface to store persistent data This allows for changing backend storage engines

func NewStore

func NewStore(se StorageEngine) (Store, error)

NewStore returns a handle to a store. Currently there is a single backend - so you can use DefautlStore instead of this method

func Open

func Open() (Store, error)

Open is what should generally be used to get access to the store. There is currently a single backend - so no need to specify