本文轉自https://blog.csdn.net/jinnianshilongnian/article/details/84703441,好文要頂,感謝博主分享!
Mysql客戶端
lua-resty-mysql是爲基於cosocket API的ngx_lua提供的Lua Mysql客戶端,通過它可以完成Mysql的操作。默認安裝OpenResty時已經自帶了該模塊,使用文檔可參考https://github.com/openresty/lua-resty-mysql。
1、編輯test_mysql.lua
local function close_db(db)
if not db then
return
end
db:close()
end
local mysql = require("resty.mysql")
--創建實例
local db, err = mysql:new()
if not db then
ngx.say("new mysql error : ", err)
return
end
--設置超時時間(毫秒)
db:set_timeout(1000)
local props = {
host = "127.0.0.1",
port = 3306,
database = "mysql",
user = "root",
password = "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
--刪除表
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
--創建表
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, "<br/>")
--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, "<br/>")
--查詢
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, "<br/>")
end
end
ngx.say("<br/>")
--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, "<br/>")
end
end
--刪除
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, "<br/>")
close_db(db)
對於新增/修改/刪除會返回如下格式的響應:
{
insert_id = 0,
server_status = 2,
warning_count = 1,
affected_rows = 32,
message = nil
}
affected_rows表示操作影響的行數,insert_id是在使用自增序列時產生的id。
對於查詢會返回如下格式的響應:
{
{ id= 1, ch= "hello"},
{ id= 2, ch= "hello2"}
}
null將返回ngx.null。
2、example.conf配置文件
location /lua_mysql {
default_type 'text/html';
lua_code_cache on;
content_by_lua_file /usr/example/lua/test_mysql.lua;
}
3、訪問如http://192.168.1.2/lua_mysql?ch=hello進行測試,得到如下結果
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
客戶端目前還沒有提供預編譯SQL支持(即佔位符替換位置變量),這樣在入參時記得使用ngx.quote_sql_str進行字符串轉義,防止sql注入;連接池和之前Redis客戶端完全一樣就不介紹了。
對於Mysql客戶端的介紹基本夠用了,更多請參考https://github.com/openresty/lua-resty-mysql。
其他如MongoDB等數據庫的客戶端可以從github上查找使用。