How to use http and C_json modules in Openresty

This article mainly introduces how to use the http and C_json modules in Openresty. It is very detailed and has a certain reference value. Friends who are interested must finish it!

Http client

Openresty does not provide a default Http client, so you need to download a third-party http client.

Download lua-resty-http to the lualib directory and download it using the following command:

Cd / usr/example/lualib/resty/ wget https://raw.githubusercontent.com/pintsized/lua-resty-http/master/lib/resty/http_headers.lua wget https://raw.githubusercontent.com/pintsized/lua-resty-http/master/lib/resty/http.lua

The address of the lua-resty-http module is https://github.com/pintsized/lua-resty-http

After successful installation, the lua_http module is introduced through require ("resty.http"), which has the following api methods:

Syntax: httpc = http.new () to create a http object

Syntax: res, err = httpc:request_uri (uri, params) gets the content based on the parameters, including:

Status status code

Headers response header

Body response body

Vim / usr/example/lua/test_http.lua, write the following code:

Local http = require ("resty.http") local httpc = http.new () local resp, err = httpc:request_uri ("http://s.taobao.com", {method =" GET ", path =" / search?q=hello ", headers = {[" User-Agent "] =" Mozilla/5.0 (Windows NT 6.1) WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/40.0.2214.111 Safari/537.36 "}) if not resp then ngx.say (" request error: ", err) return end ngx.status = resp.status for k, v in pairs (resp.headers) do if k ~ =" Transfer-Encoding "and k ~ =" Connection "then ngx.header [k] = v end end ngx.say (resp.body) httpc:close ()

Vim / usr/example/example.conf plus the following configuration:

Location / lua_http {default_type 'text/html'; lua_code_cache on; content_by_lua_file / usr/example/lua/test_http.lua;}

In the http section of Nginx's configuration file nginx.conf, add the following dns resolution:

Vim / usr/servers/nginx/conf/nginx.conf

Resolver 8.8.8.8

Browser access: the http://116.196.177.123/lua_http, browser will display Taobao's search page.

Lua_cjson module

Json is a common data exchange format, which is often used in http communication protocol and other data transmission fields. The lua_cjson module is embedded in openresty by default to serialize data.

Address of lua_cjson module: https://www.kyne.com.au/~mark/software/lua-cjson-manual.html

The commonly used API is as follows:

Local cjson = require "cjson" to get a cjson object

Local str = cjson.encode (obj) obj converted to string

Local obj = cjson.decode (str) convert string to obj

Vim / usr/example/lua/test_cjson.lua, add the following:

Local cjson = require ("cjson") local obj = {id = 1, name = "zhangsan", age = nil, is_male = false, hobby = {"film", "music", "read"}} local str = cjson.encode (obj) ngx.say (str, ") str ='{" hobby ": [" film "," music "," read "]," is_male ": false," name ":" zhangsan " "id": 1, "age": null} 'local obj = cjson.decode (str) ngx.say (obj.age, ") ngx.say (obj.age = = nil,") ngx.say (obj.age = = cjson.null, ") ngx.say (obj.hobby [1],")

Vim / usr/example/example.conf adds the following:

Location ~ / lua_cjson {default_type 'text/html'; lua_code_cache on; content_by_lua_file / usr/example/lua/test_cjson.lua;}

Access http://116.196.177.123/lua_cjson on the browser, and the browser displays the following:

{"hobby": ["film", "music", "read"], "is_male": false, "name": "zhangsan", "id": 1} nullfalsetruefilm is all the content of this article "how to use http and C_json modules in Openresty". Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!