Nginx+Lua+Redis 对请求进行限制

local redis = require "resty.redis"
local cache = redis.new()
cache.connect(cache, '127.0.0.1', '6379')
local res = cache:get("foo")
if res==ngx.null then
ngx.say("This is Null")
return
end
ngx.say(res)

local mysql = require "resty.mysql"
local db, err = mysql:new()
if not db then
ngx.say("failed to instantiate mysql: ", err)
return
end

db:set_timeout(1000) -- 1 sec

-- or connect to a unix domain socket file listened
-- by a mysql server:
--     local ok, err, errno, sqlstate =
--           db:connect{
--              path = "/path/to/mysql.sock",
--              database = "ngx_test",
--              user = "ngx_test",
--              password = "ngx_test" }

local ok, err, errno, sqlstate = db:connect{
host = "127.0.0.1",
port = 3306,
database = "test",
user = "root",
password = "123456",
max_packet_size = 1024 * 1024 }

if not ok then
ngx.say("failed to connect: ", err, ": ", errno, " ", sqlstate)
return
end

ngx.say("connected to mysql.")

local res, err, errno, sqlstate =
db:query("drop table if exists cats")
if not res then
ngx.say("bad result: ", err, ": ", errno, ": ", sqlstate, ".")
return
end

res, err, errno, sqlstate =
db:query("create table cats "
.. "(id serial primary key, "
.. "name varchar(5))")
if not res then
ngx.say("bad result: ", err, ": ", errno, ": ", sqlstate, ".")
return
end

ngx.say("table cats created.")

res, err, errno, sqlstate =
db:query("insert into cats (name) "
.. "values (\'Bob\'),(\'\'),(null)")
if not res then
ngx.say("bad result: ", err, ": ", errno, ": ", sqlstate, ".")
return
end

ngx.say(res.affected_rows, " rows inserted into table cats ",
"(last insert id: ", res.insert_id, ")")

-- run a select query, expected about 10 rows in
-- the result set:
res, err, errno, sqlstate =
db:query("select * from cats order by id asc", 10)
if not res then
ngx.say("bad result: ", err, ": ", errno, ": ", sqlstate, ".")
return
end

local cjson = require "cjson"
ngx.say("result: ", cjson.encode(res))

-- put it into the connection pool of size 100,
-- with 10 seconds max idle timeout
local ok, err = db:set_keepalive(10000, 100)
if not ok then
ngx.say("failed to set keepalive: ", err)
return
end

-- or just close the connection right away:
-- local ok, err = db:close()
-- if not ok then
--     ngx.say("failed to close: ", err)
--     return
-- end
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