学习-1

日志包使用

"github.com/yezihack/colorlog"

操作redis使用redigo包

"github.com/garyburd/redigo/redis"

在main函数中连接数据库，再调用其他函数，其他函数里实现学习的内容。

func main() {
    c, err := redis.Dial("tcp", "127.0.0.1:6379")
    if err != nil {
        fmt.Println("Connect to redis error", err)
        return
    }
    defer c.Close()
    SingleKey(c)
    SingleExpireKey(c)
    SingleKeyExist(c)
    SingleKeyDelete(c)
    SinglePersistKey(c)
}

接下来其他函数里学习一些对单个Key的操作。

---

给单个key赋值，然后获取值。

Code

func SingleKey(c redis.Conn) {
    colorlog.Info("Func OneKey...")
    _, err := c.Do("SET", "FoxKey", "Fox")
    if err != nil {
        colorlog.Error("redis set failed: " + err.Error())
        return
    }

    valueOfFoxKey, err := redis.String(c.Do("GET", "FoxKey"))
    if err != nil {
        colorlog.Error("redis get failed: " + err.Error())
    } else {
        fmt.Printf("Get FoxKey: %v \n", valueOfFoxKey)
    }
}

Output

1.png

给单个key设置过期时间并赋值，然后获取值。

Code

func SingleExpireKey(c redis.Conn) {
    colorlog.Info("Func SingleExpireKey...")
    _, err := c.Do("SET", "FoxExpireKey", "Fox", "EX", "2")
    if err != nil {
        colorlog.Error("redis set failed: " + err.Error())
        return
    }

    valueOfFoxExpireKey, err := redis.String(c.Do("GET", "FoxExpireKey"))
    if err != nil {
        colorlog.Error("redis get failed: " + err.Error())
    } else {
        fmt.Printf("Get Value of Fox Expire Key: %v \n", valueOfFoxExpireKey)
    }

    colorlog.Debug("Waiting for the key expired")
    time.Sleep(3 * time.Second)

    valueOfFoxExpireKey, err = redis.String(c.Do("GET", "FoxExpireKey"))
    if err != nil {
        colorlog.Error("redis get failed: " + err.Error())
    } else {
        fmt.Printf("Get Value of Fox Expire Key %v \n", valueOfFoxExpireKey)
    }
}

Output

2.png

判断单个key是否存在

Code

func SingleKeyExist(c redis.Conn) {
    colorlog.Info("Func SingleKeyExist...")
    _, err := c.Do("SET", "KobeKey", "Kobe")
    if err != nil {
        colorlog.Error("redis set failed: " + err.Error())
        return
    }
    isExist, _ := c.Do("EXISTS", "KobeKey")
    if isExist == int64(1) {
        fmt.Println("The KobeKey exists")
    } else {
        fmt.Println("The KobeKey doesn't exist")
    }
    isExist, _ = c.Do("EXISTS", "FakeKey")
    if isExist == int64(1) {
        fmt.Println("The FakeKey exists")
    } else {
        fmt.Println("The FakeKey doesn't exist")
    }
}

Output

3.png

删除单个key

Code

func SingleKeyDelete(c redis.Conn) {
    colorlog.Info("Func SingleKeyDelete...")
    _, err := c.Do("SET", "AllenKey", "Allen")
    if err != nil {
        colorlog.Error("redis set failed: " + err.Error())
        return
    }
    del, err := c.Do("DEL", "AllenKey")
    if err != nil {
        colorlog.Error(err.Error())
    } else {
        if del == int64(1) {
            fmt.Println("Allen key deleted successfully")
        } else {
            fmt.Println("Allen key deleted failed, key may doesn't exist")
        }
    }

    del, err = c.Do("DEL", "TracyKey")
    if err != nil {
        colorlog.Error(err.Error())
    } else {
        if del == int64(1) {
            fmt.Println("Tracy key deleted successfully")
        } else {
            fmt.Println("Tracy key deleted failed, key may doesn't exist")
        }
    }
}

Output

4.png

持久化单个key

Code

func SinglePersistKey(c redis.Conn) {
    colorlog.Info("Func SinglePersistKey...")
    _, err := c.Do("SET", "PersistKey", "Vince", "EX", "10")
    if err != nil {
        colorlog.Error("redis set failed: " + err.Error())
        return
    }

    valueOfPersistKey, err := redis.String(c.Do("GET", "PersistKey"))
    if err != nil {
        colorlog.Error("redis get failed: " + err.Error())
    } else {
        fmt.Println(valueOfPersistKey)
    }

    // make key persistent
    result, err := c.Do("PERSIST", "PersistKey")
    if err != nil {
        colorlog.Error(err.Error())
    } else if result == int64(1) {
        fmt.Println("Persist key successfully")
    } else if result == int64(0) {
        fmt.Println("key persisted already")
    }

    colorlog.Debug("After 10 seconds, the key will not expire, we can still get the value")
    time.Sleep(10 * time.Second)

    valueOfPersistKey, err = redis.String(c.Do("GET", "PersistKey"))
    if err != nil {
        colorlog.Error("redis get failed: " + err.Error())
    } else {
        fmt.Println(valueOfPersistKey)
    }
}

Output

image.png