使用go-mysql-server 开发自己的mysql server

go-mysql-server是一个golang 的mysql server 协议实现包，使用此工具我们可以用来做好多方便的东西

• 基于mysql 协议暴露自己的本地文件为sql 查询
• 基于mysql 协议灵活的暴露rest 服务的接口查询为sql
• 基于mysql 协议方便对于一些数据的查询分析
• 基于mysql 协议暴露k8s 资源为sql 查询（类似fuse 文件系统？）
• 基于mysql 协议查询git仓库代码
  。。。

一个简单的demo

一个golang 版的简单mysql server

• 项目初始化（go mod ）

go mod init github.com/rongfengliang/my-mysqlserver

• main.go

package main

import (
 "time"

 "gopkg.in/src-d/go-mysql-server.v0"
 "gopkg.in/src-d/go-mysql-server.v0/auth"
 "gopkg.in/src-d/go-mysql-server.v0/mem"
 "gopkg.in/src-d/go-mysql-server.v0/server"
 "gopkg.in/src-d/go-mysql-server.v0/sql"
)

// Example of how to implement a MySQL server based on a Engine:
//
// ```
// > mysql --host=127.0.0.1 --port=5123 -u user -ppass db -e "SELECT * FROM mytable"
// +----------+-------------------+-------------------------------+---------------------+
// | name | email | phone_numbers | created_at |
// +----------+-------------------+-------------------------------+---------------------+
// | John Doe | john@doe.com | ["555-555-555"] | 2018-04-18 09:41:13 |
// | John Doe | johnalt@doe.com | [] | 2018-04-18 09:41:13 |
// | Jane Doe | jane@doe.com | [] | 2018-04-18 09:41:13 |
// | Evil Bob | evilbob@gmail.com | ["555-666-555","666-666-666"] | 2018-04-18 09:41:13 |
// +----------+-------------------+-------------------------------+---------------------+
// ```
func main() {
 engine := sqle.NewDefault()
 engine.AddDatabase(createTestDatabase())
 engine.AddDatabase(sql.NewInformationSchemaDatabase(engine.Catalog))

 config := server.Config{
  Protocol: "tcp",
  Address: "localhost:3306",
  Auth: auth.NewNativeSingle("root", "", auth.AllPermissions),
 }

 s, err := server.NewDefaultServer(config, engine)
 if err != nil {
  panic(err)
 }

 s.Start()
}

func createTestDatabase() *mem.Database {
 const (
  dbName = "mydb"
  tableName = "mytable"
 )

 db := mem.NewDatabase(dbName)
 table := mem.NewTable(tableName, sql.Schema{
  {Name: "name", Type: sql.Text, Nullable: false, Source: tableName},
  {Name: "email", Type: sql.Text, Nullable: false, Source: tableName},
  {Name: "phone_numbers", Type: sql.JSON, Nullable: false, Source: tableName},
  {Name: "created_at", Type: sql.Timestamp, Nullable: false, Source: tableName},
 })

 db.AddTable(tableName, table)
 ctx := sql.NewEmptyContext()
 table.Insert(ctx, sql.NewRow("John Doe", "john@doe.com", []string{"555-555-555"}, time.Now()))
 table.Insert(ctx, sql.NewRow("John Doe", "johnalt@doe.com", []string{}, time.Now()))
 table.Insert(ctx, sql.NewRow("Jane Doe", "jane@doe.com", []string{}, time.Now()))
 table.Insert(ctx, sql.NewRow("Evil Bob", "evilbob@gmail.com", []string{"555-666-555", "666-666-666"}, time.Now()))
 return db
}

• 添加依赖

go mod tidy

• 构建

go build my-server

• 运行

./my-server

• 连接查询

mysql -uroot -h127.0.0.1

效果

select * from mytable;
+----------+-------------------+-------------------------------+---------------------+
| name | email | phone_numbers | created_at |
+----------+-------------------+-------------------------------+---------------------+
| John Doe | john@doe.com | ["555-555-555"] | 2019-05-18 10:56:31 |
| John Doe | johnalt@doe.com | [] | 2019-05-18 10:56:31 |
| Jane Doe | jane@doe.com | [] | 2019-05-18 10:56:31 |
| Evil Bob | evilbob@gmail.com | ["555-666-555","666-666-666"] | 2019-05-18 10:56:31 |

说明

go-mysql-server 已经包好了好多内置的sql 函，同时我们也可以自己搞一些扩展开发，一个很强大的工具

参考资料

https://github.com/src-d/go-mysql-server