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router: Lua http router for nginx-module-lua

Installation

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CentOS/RHEL 7 or Amazon Linux 2

yum -y install https://extras.getpagespeed.com/release-latest.rpm
yum -y install lua-resty-router

CentOS/RHEL 8+, Fedora Linux, Amazon Linux 2023

yum -y install https://extras.getpagespeed.com/release-latest.rpm
yum -y install lua5.1-resty-router

To use this Lua library with NGINX, ensure that nginx-module-lua is installed.

This document describes lua-resty-router v0.1.0 released on Jun 26 2017.

lua-resty-router - Lua http router for the ngx_lua

Status

This library is considered production ready.

Description

This Lua library is a http router for the ngx_lua nginx module:

http://wiki.nginx.org/HttpLuaModule

This Lua library takes advantage of ngx_lua's cosocket API, which ensures 100% nonblocking behavior.

Note that at least ngx_lua 0.5.0rc29 or OpenResty 1.0.15.7 is required.

Synopsis

    server {
        location /test {
            content_by_lua '
                local Router = require "resty.router"
              router = Router:new()
              router:get("/a/:b/:c", function(params)
                ngx.print(params["b"].."-"..parmams["c"])
              end)
              router:post("/b/c/*.html", function(params)
                ngx.print("echo html")
              end)
              router:any("/c/d/", function(params)
                ngx.print("hello, world")
              end)
            ';
        }
    }

Methods

The key argument provided in the following methods will be automatically escaped according to the URI escaping rules before sending to the memcached server.

new

syntax: r, err = router:new()

Creates a router object, never return an error.

route

Using GET, POST, HEAD, PUT, PATCH, DELETE, ANY and OPTIONS

local R = require("resty.router")
local router = R:new()
router:get("/GetRoute", handler)
router:post("/PostRoute", handler)
router:head("/HeadRoute", handler)
router:put("/PutRoute", handler)
router:delete("/DeleteRoute", handler)
router:patch("/PatchRoute", handler)
router:options("/OptionsRoute", handler)
router:any("/AnyRoute", handler)
router:run()

Parameters in path

    local R = require("resty.router")
    local router = R:new()

    -- catch all when on route is match
    router:get("/*", function(params) -- /* or * is ok
        ngx.say("catch all") 
        ngx.exit(200)
    end)

    -- This handler will match /user/john but will not match neither /user/ or /user
    router:get("/user/:name", function(params)
        local name = params["name"]
        ngx.print("Hello", name)
        ngx.exit(200)
    end)

    -- However, this one will match /user/john/ and also /user/john/send
    -- If no other routers match /user/john, it will redirect to /user/john/
    router.get("/user/:name/*", function(params)
        local name = params("name")
        ngx.print("Hello", name)
        ngx.exit(200)
    end)

    -- This one will match /user/jhon/send.html, also match any uri start with /user/jhon/ and end with .html
    router:get("/user/jhon/*.html", function(params)
        ngx.print("Hello")
        ngx.exit(200)
    end)

    router:run()

handler

Type of parameter handler should be function or string, when type is:

  • function, handler would be called when uri is matched
  • string, router would require a.b, when ret type is table, search method handle, if ret type is function, return function would be called.

Tips

  • '*' rule can be used at the end of the route
  • throw http code 500 when route conflicts

run

Method run would find route, and callback the handler. when not handler was found and notfound_handler is set, callback the handler.

    local R = require("resty.router")
    local router = R:new()
    router:run() -- or router:run(notfound_handler)

Limitations

  • This library cannot be used in code contexts like set_by_lua*, log_by_lua*, and header_filter_by_lua* where the ngx_lua cosocket API is not available.
  • The resty.memcached object instance cannot be stored in a Lua variable at the Lua module level, because it will then be shared by all the concurrent requests handled by the same nginx worker process (see http://wiki.nginx.org/HttpLuaModule#Data_Sharing_within_an_Nginx_Worker ) and result in bad race conditions when concurrent requests are trying to use the same resty.memcached instance. You should always initiate resty.memcached objects in function local variables or in the ngx.ctx table. These places all have their own data copies for each request.

GitHub

You may find additional configuration tips and documentation for this module in the GitHub repository for nginx-module-router.