lbase

README

lbase is simple key/value storage based on syndtr/goleveldb library.

Summary

• Written on tiny Go
• Go library
• Require Go version >= 1.2
• Simple API
• Persistent key/value storage
• Use LSM-tree engine
• Has mock object for tests

Install

go get github.com/wmentor/lbase

Usage

package main

import (
  "fmt"

  "github.com/wmentor/lbase"
)

func main() {
  db, err := lbase.Open("path=./base")
	if err != nil {
		panic(err)
	}
	defer db.Close()

  db.Set([]byte("1"), []byte("11"))
  db.Set([]byte("10"), []byte("1100"))
  db.Set([]byte("11"), []byte("1111"))
  db.Set([]byte("12"), []byte("1122"))
  db.Set([]byte("3"), []byte("33"))
  db.Set([]byte("4"), []byte("44"))
  db.Set([]byte("5"), []byte("55"))
  db.Set([]byte("6"), []byte("66"))

  fmt.Println(string(db.Get([]byte("5")))) // 55

  db.Get([]byte("7")) // nil

  fmt.Println(db.Has([]byte("5"))) // true
  db.Set([]byte("5"), nil) // remove key []byte("5")
  fmt.Println(db.Has([]byte("5"))) // false

  db.Prefix([]byte("1"), func(k, v []byte) bool {
    fmt.Println(string(k) + " " + string(v))
    return true
  })
  /* print:
  1 11
  10 1100
  11 1111
  12 1122
  */

  db.Range([]byte("12"), []byte("4"), func(k, v []byte) bool {
    fmt.Println(string(k) + " " + string(v))
    return true
  })
  /* print:
  12 1122
  2 22
  3 33
  */
}

Work with global context:

package main

import (
  "github.com/wmentor/lbase"
)

func main() {
  _, err := lbase.Open("path=./base global=1")
	if err != nil {
		panic(err)
	}
	defer lbase.Close()

  lbase.Set([]byte("1"), []byte("11"))
  lbase.Set([]byte("10"), []byte("1100"))
  ...
}

Work with test context:

package main

import (
  "github.com/wmentor/lbase"
)

func main() {
  _, err := lbase.Open("test=1 global=1")
	if err != nil {
		panic(err)
	}
	defer lbase.Close()

  lbase.Set([]byte("1"), []byte("11"))
  lbase.Set([]byte("10"), []byte("1100"))
  ...
}

Documentation

Index

• Variables
• func Close()
• func Delete(key []byte)
• func Get(key []byte) []byte
• func Has(key []byte) bool
• func Prefix(prefix []byte, fn PairIteratorFunc)
• func Range(from []byte, to []byte, fn PairIteratorFunc)
• func Set(key, value []byte)
• type DB
  • func Open(params string) (DB, error)
• type PairIteratorFunc

Variables

var (
	ErrNoPath error = errors.New("db path not entered")
)

Functions

func Close

func Close()

func Delete

func Delete(key []byte)

func Get

func Get(key []byte) []byte

func Has

func Has(key []byte) bool

func Prefix

func Prefix(prefix []byte, fn PairIteratorFunc)

func Range

func Range(from []byte, to []byte, fn PairIteratorFunc)

func Set

func Set(key, value []byte)

Types

type DB

type DB interface {
	Delete(key []byte)
	Get(key []byte) []byte
	Has(key []byte) bool
	Set(key, value []byte)
	Prefix(prefix []byte, fn PairIteratorFunc)
	Range(from []byte, to []byte, fn PairIteratorFunc)
	Close()
}

func Open

func Open(params string) (DB, error)

type PairIteratorFunc

type PairIteratorFunc func(key []byte, value []byte) bool