Mysql客户端

lua-resty-mysql是为基于cosocket API的ngx_lua提供的Lua Mysql客户端，经过它能够完成Mysql的操做。默认安装OpenResty时已经自带了该模块，使用文档可参考https://github.com/openresty/lua-resty-mysql。html

1. 编辑mysql/test_mysql.lua

local function close_db( db )

if not db then

return

end

db:close()

end

local mysql = require("resty.mysql")

-- 建立实例

local db, err = mysql:new()

if not db then

ngx.say("new mysql error:", err)

return

end

-- 设置超时时间(毫秒)

db:set_timeout(5000)

local props = {

host = "172.19.237.44",

port = 3306,

database = "fuhuitest",

user = "root",

password = "wsy@123456"

}

local res, err, errno, sqlstate = db:connect(props)

if not res then

ngx.say("connect to mysql error : ", err, " , errno : ", errno, " , sqlstate : ", sqlstate)

return close_db(db)

end

-- 删除表

local drop_table_sql = "drop table if exists test"

res, err, errno, sqlstate = db:query(drop_table_sql)

if not res then

ngx.say("drop table error : ", err, " , errno : ", errno, " , sqlstate : ", sqlstate)

return close_db(db)

end

-- 建立表

local create_table_sql = "create table test(id int primary key auto_increment, ch varchar(100))"

res, err, errno, sqlstate = db:query(create_table_sql)

if not res then

ngx.say("create table error : ", err, " , errno : ", errno, " , sqlstate : ", sqlstate)

return close_db(db)

end

-- 插入

local insert_sql = "insert into test (ch) values('hello')"

res, err, errno, sqlstate = db:query(insert_sql)

if not res then

ngx.say("insert error : ", err, " , errno : ", errno, " , sqlstate : ", sqlstate)

return close_db(db)

end

res, err, errno, sqlstate = db:query(insert_sql)

ngx.say("insert rows : ", res.affected_rows, " , id : ", res.insert_id, "
")

-- 更新

local update_sql = "update test set ch = 'hello2' where id =" .. res.insert_id

res, err, errno, sqlstate = db:query(update_sql)

if not res then

ngx.say("update error : ", err, " , errno : ", errno, " , sqlstate : ", sqlstate)

return close_db(db)

end

ngx.say("update rows : ", res.affected_rows, "
")

-- 查询

local select_sql = "select id, ch from test"

res, err, errno, sqlstate = db:query(select_sql)

if not res then

ngx.say("select error : ", err, " , errno : ", errno, " , sqlstate : ", sqlstate)

return close_db(db)

end

for i, row in ipairs(res) do

for name, value in pairs(row) do

ngx.say("select row ", i, " : ", name, " = ", value, "
")

end

end

ngx.say("
")

--防止sql注入

local ch_param = ngx.req.get_uri_args()["ch"] or ''

--使用ngx.quote_sql_str防止sql注入

local query_sql = "select id, ch from test where ch = " .. ngx.quote_sql_str(ch_param)

res, err, errno, sqlstate = db:query(query_sql)

if not res then

ngx.say("select error : ", err, " , errno : ", errno, " , sqlstate : ", sqlstate)

return close_db(db)

end

for i, row in ipairs(res) do

for name, value in pairs(row) do

ngx.say("select row ", i, " : ", name, " = ", value, "
")

end

end

-- 删除

local delete_sql = "delete from test"

res, err, errno, sqlstate = db:query(delete_sql)

if not res then

ngx.say("delete error : ", err, " , errno : ", errno, " , sqlstate : ", sqlstate)

return close_db(db)

end

ngx.say("delete rows : ", res.affected_rows, "
")

close_db(db)

对于新增/修改/删除会返回以下格式的响应：mysql

{

insert_id = 0,

server_status = 2,

warning_count = 1,

affected_rows = 32,

message = nil

}

affected_rows表示操做影响的行数，insert_id是在使用自增序列时产生的id。

对于查询会返回以下格式的响应：git

{

{ id= 1, ch= "hello"},

{ id= 2, ch= "hello2"}

}

null将返回ngx.null。github

2. openResty.conf配置文件

location /lua_mysql {

default_type 'text/html';

lua_code_cache on;

content_by_lua_file /usr/openResty/lua/mysql/test_mysql.lua;

}

3. 访问如http://127.0.0.1/lua_mysql?ch=hello进行测试，获得以下结果

insert rows : 1 , id : 2

update rows : 1

select row 1 : ch = hello

select row 1 : id = 1

select row 2 : ch = hello2

select row 2 : id = 2

select row 1 : ch = hello

select row 1 : id = 1

delete rows : 2

客户端目前尚未提供预编译SQL支持(即占位符替换位置变量)，这样在入参时记得使用ngx.quote_sql_str进行字符串转义，防止sql注入；链接池和以前Redis客户端彻底同样就不介绍了。

对于Mysql客户端的介绍基本够用了，更多请参考https://github.com/openresty/lua-resty-mysql。web