Api主要代码，点击我找跟此文章标题一样的commit，此阶段源码

package dbops

import (
    "log"
    _ "github.com/go-sql-driver/mysql"
    "database/sql"
)

func AddUserCredential(loginName string, pwd string) error  {
    stmtIns, err := dbConn.Prepare("INSERT INTO users (login_name, pwd) VALUES (?,?)")
    if err!=nil {
        return err
    }
    _, err = stmtIns.Exec(loginName, pwd)
    if err!=nil {
        return err
    }

    defer stmtIns.Close() // 性能消耗较大

    return nil
}

func GetUserCredential(loginName string) (string, error)  {
    stmtOut, err := dbConn.Prepare("SELECT pwd FROM users WHERE login_name = ?")
    if err != nil {
        log.Printf("%s", err)
        return "", err
    }

    var pwd string
    err = stmtOut.QueryRow(loginName).Scan(&pwd)
    // noRows 没有结果返回
    if err != nil && err != sql.ErrNoRows {
        return "", err
    }
    defer stmtOut.Close()
    return pwd, nil
}

func DeleteUser(loginName string, pwd string) error {
    stmtDel, err := dbConn.Prepare("DELETE FROM users WHERE login_name = ?")
    if err != nil {
        log.Printf("DeleteUser error: %s", err)
        return err
    }
    stmtDel.Exec(loginName, pwd)
    if err != nil && err != sql.ErrNoRows {
        return err
    }
    defer stmtDel.Close()
    return nil
}

测试

package dbops

import (
    "testing"
)

func clearTables()  {
    dbConn.Exec("truncate users")
    dbConn.Exec("truncate video_info")
    dbConn.Exec("truncate comments")
    dbConn.Exec("truncate sessions")
}

func TestMain(m *testing.M) {
    clearTables()
    m.Run()
    clearTables()
}

func TestUserWorkFlow(t *testing.T)  {
    t.Run("Add", testAddUser)
    t.Run("Get", testGetUser)
    t.Run("Del", testDeleteUser)
    t.Run("Reget", testRegetUser)
}

func testAddUser(t *testing.T)  {
    err := AddUserCredential("tuzisir", "123")
    if err != nil {
        // %v 是以默认方式打印此值
        t.Errorf("Error of AddUser: %v", err)
    }
}

func testGetUser(t *testing.T)  {
    pwd, err := GetUserCredential("tuzisir")
    if pwd != "123" || err != nil {
        t.Errorf("Error of GetUser: %v", err)
    }
}

func testDeleteUser(t *testing.T)  {
    err := DeleteUser("tuzisir", "123")
    if err != nil {
        t.Errorf("Error of DeleteUser: %v", err)
    }
}

func testRegetUser(t *testing.T) {
    pwd, err := GetUserCredential("tuzisir")
    if err != nil {
        t.Errorf("Error of RegetUser: %v", err)
    }

    if pwd == "" {
        t.Errorf("Reget user test fail")
    }
}

结果

image.png