mlsr/tests/buntDB_test.go

// Package tests
// @Author: Wang Feng
// @Description: buntDB-一种开源的内存键值库
// 源代码：https://github.com/tidwall/buntdb
// 使用方法：https://segmentfault.com/a/1190000022102931
//		   https://darjun.github.io/2020/03/21/godailylib/buntdb/
// @Version: 0.1.0
// @Date: 2022/4/6 16:00
// @Copyright: MIN-Group；国家重大科技基础设施——未来网络北大实验室；深圳市信息论与未来网络重点实验室
//

package tests

import (
	"fmt"
	"github.com/tidwall/buntdb"
	"log"
	"testing"
)

//
//  TestSetAndGet_In_UpdateAndView
//  @Description: 创建数据库，设置数据库参数
//  @param t
//
func TestSetAndGet_In_UpdateAndView(t *testing.T) {
	db, err := buntdb.Open(":memory:")
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()

	db.Update(func(tx *buntdb.Tx) error {
		oldValue, replaced, err := tx.Set("testkey", "testvalue", nil)
		if err != nil {
			return err
		}

		fmt.Printf("old value:%q replaced:%t\n", oldValue, replaced)
		return nil
	})

	db.View(func(tx *buntdb.Tx) error {
		value, err := tx.Get("testkey")
		if err != nil {
			return err
		}

		fmt.Println("value is:", value)
		return nil
	})
}

//
//  TestAscend
//  @Description:
//  Ascend()方法接收一个索引名，然后以该索引定义的顺序遍历所有键值对
//	如果未指定索引名，则根据键升序遍历
//  @param t
//
func TestAscend(t *testing.T) {
	db, err := buntdb.Open(":memory:")
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()

	db.Update(func(tx *buntdb.Tx) error {
		data := map[string]string{
			"a": "apple",
			"b": "banana",
			"p": "pear",
			"o": "orange",
		}
		for key, value := range data {
			tx.Set(key, value, nil)
		}
		return nil
	})

	db.View(func(tx *buntdb.Tx) error {
		var count int
		tx.Ascend("", func(key, value string) bool {
			fmt.Printf("key:%s value:%s\n", key, value)
			count++
			if count >= 3 {
				return false
			}
			return true
		})
		return nil
	})
}

//
//  TestCreatIndex
//  @Description: buntDB将数据以键排序存储到b-tree中
// 可以创建自定义索引，这样就可以对值进行排序了。传入索引名、键名、值大小判断方法
//  @param t
//
func TestCreatIndex(t *testing.T) {
	db, err := buntdb.Open(":memory:")
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()

	db.CreateIndex("names", "user:*:name", buntdb.IndexString)
	db.Update(func(tx *buntdb.Tx) error {
		tx.Set("user:1:name", "tom", nil)
		tx.Set("user:2:name", "Randi", nil)
		tx.Set("user:3:name", "jane", nil)
		tx.Set("user:4:name", "Janet", nil)
		tx.Set("user:5:name", "Paula", nil)
		tx.Set("user:6:name", "peter", nil)
		tx.Set("user:7:name", "Terri", nil)
		return nil
	})

	db.View(func(tx *buntdb.Tx) error {
		tx.Ascend("names", func(key, value string) bool {
			fmt.Printf("%s: %s\n", key, value)
			return true
		})
		return nil
	})
}

func TestStructIndex(t *testing.T) {
	db, _ := buntdb.Open(":memory:")
	defer db.Close()

	db.CreateIndex("first_name", "user:*", buntdb.IndexJSON("name.first"))
	db.CreateIndex("age", "user:*", buntdb.IndexJSON("age"))
	db.Update(func(tx *buntdb.Tx) error {
		tx.Set("user:1", `{"name":{"first":"zhang","last":"san"},"age":18}`, nil)
		tx.Set("user:2", `{"name":{"first":"li","last":"si"},"age":27`, nil)
		tx.Set("user:3", `{"name":{"first":"wang","last":"wu"},"age":32}`, nil)
		tx.Set("user:4", `{"name":{"first":"sun","last":"qi"},"age":8}`, nil)
		return nil
	})

	// 不行。buntDB只能存key和value均是string类型的键值对。
}

//
//  TestJSONIndex
//  @Description: 当值为json字符串时，可以按照json字符串中的键进行排序
//  @param t
//
func TestJSONIndex(t *testing.T) {
	db, _ := buntdb.Open(":memory:")
	defer db.Close()

	db.CreateIndex("first_name", "user:*", buntdb.IndexJSON("name.first"))
	db.CreateIndex("age", "user:*", buntdb.IndexJSON("age"))
	db.Update(func(tx *buntdb.Tx) error {
		tx.Set("user:1", `{"name":{"first":"zhang","last":"san"},"age":18}`, nil)
		tx.Set("user:2", `{"name":{"first":"li","last":"si"},"age":27}`, nil)
		tx.Set("user:3", `{"name":{"first":"wang","last":"wu"},"age":32}`, nil)
		tx.Set("user:4", `{"name":{"first":"sun","last":"qi"},"age":8}`, nil)
		return nil
	})

	db.View(func(tx *buntdb.Tx) error {
		fmt.Println("Order by first name")
		tx.Ascend("first_name", func(key, value string) bool {
			fmt.Printf("%s: %s\n", key, value)
			return true
		})

		fmt.Println("Order by age")
		tx.Ascend("age", func(key, value string) bool {
			fmt.Printf("%s: %s\n", key, value)
			return true
		})

		fmt.Println("Order by age range 18-30")
		tx.AscendRange("age", `{"age":18}`, `{"age":30}`, func(key, value string) bool {
			fmt.Printf("%s: %s\n", key, value)
			return true
		})
		return nil
	})
}

//
//  TestExpiresTime
//  @Description: 在增加数据库条目时，设置过期时间
//  @param t
//
func TestExpiresTime(t *testing.T) {
	db, _ := buntdb.Open(":memory:")
	defer db.Close()

	db.Update(func(tx *buntdb.Tx) error {
		//tx.Set("testkey", "testvalue", &buntdb.SetOptions{Expires: true, TTL: time.Second})
		tx.Set("testkey", "testvalue",nil)
		return nil
	})

	db.View(func(tx *buntdb.Tx) error {
		value, _ := tx.Get("testkey")
		fmt.Println("value is:", value)
		return nil
	})

	//time.Sleep(time.Second)

	db.View(func(tx *buntdb.Tx) error {
		value, _ := tx.Get("testkey")
		fmt.Println("after expire, value is:", value)
		return nil
	})
}