OpenResty连接Mysql，

OpenResty连接Mysql，

openresty连接mysql
lua-resty-mysql模块的官方文档地址： https://github.com/openresty/lua-resty-mysql

lua-resty-mysql - Lua MySQL client driver for ngx_lua based on the cosocket API

lua-resty-mysql模块是基于cosocket API 为ngx_lua提供的一个Lua MySQL客户端。它保证了100%非阻塞。

vim /usr/example/lua/test_mysql.lua，添加以下的代码：
 

local function close_db(db)
	if not db then
		return
	end
end

local mysql = require("resty.mysql")

local db, err = mysql:new()
if not db then
	ngx.say("new mysql error : ", err)
	return
end

db:set_timeout(1000)

--数据库配置
local props = {
	host = "10.10.0.100",
	port = 3306,
	databse = "ymdd_order",
	user = "root",
	password = "MySQL@123"

}

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

local use_database_sql = "use ymdd_order;"

res, err, errno, sqlstate = db:query(use_database_sql)
   
if not res then
         ngx.say("use database  error : ",err, " , errno : ", errno, ", sqlstate : ", sqlstate)
         return close_db(db)
end


local drop_table_sql = "drop table if exists test_lua"

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

local create_table_sql = "create table test_lua(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  
  

local insert_sql = "insert into test_lua (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, "<br/>")  
  
 
local update_sql = "update test_lua 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, "<br/>")  
  
local select_sql = "select id, ch from test_lua"  
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, "<br />")
	end
end

ngx.say("<br />")

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

local query_sql = "select id, ch from test_lua 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, "<br/>")  
   end  
end  
  

local delete_sql = "delete from test_lua"  
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, "<br/>")  
  
  
close_db(db)  

在上面的代码中，展示了基本的创表、插入数据、修改数据、查询数据、删除数据的一些功能。

其中用到的lua-resty-mysql的一些API方法：

syntax: db, err = mysql:new() 创建一个mysql数据库连接对象
syntax: ok, err = db:connect(options) 尝试远程连接mysql
host mysql的主机名
port 端口
database 数据库名
user 用户名
password 密码
charset 编码
syntax: db:set_timeout(time) 设置数据库连接超时时间
syntax: ok, err = db:set_keepalive(max_idle_timeout, pool_size) 设置连接池
syntax: ok, err = db:close() 关闭数据库
syntax: bytes, err = db:send_query(query) 发送查询
lua-resty-mysql的一些关键的API方法，见https://github.com/openresty/lua-resty-mysql#table-of-contents

vim /usr/example/example.conf 在配置文件配置：

location /lua_mysql {
   default_type 'text/html';
   lua_code_cache on;
   content_by_lua_file /usr/example/lua/test_mysql.lua;
 }