libr3: High-performance path dispatching library base on libr3 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-libr3

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

yum -y install https://extras.getpagespeed.com/release-latest.rpm
yum -y install lua5.1-resty-libr3

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

This document describes lua-resty-libr3 v1.2 released on Sep 30 2019.

---

This is Lua-Openresty implementation library base on FFI for libr3.

Status

This repository is an experimental.

Synopsis

 location / {
     content_by_lua_block {
         -- r3 router
         local r3 = require("resty.r3").new();
         local encode_json = require("cjson.safe").encode

         function foo(params) -- foo handler
             ngx.say("foo: ", encode_json(params))
         end

         -- routing
         r3:get("/foo/{id}/{name}", foo)

         -- don't forget!!!
         r3:compile()

         -- dispatch
         local ok = r3:dispatch("/foo/a/b", ngx.req.get_method())
         if not ok then
             ngx.exit(404)
         end
     }
 }

Methods

new

syntax: r3, err = r3router:new()

Creates a r3 object. In case of failures, returns nil and a string describing the error.

syntax: r3, err = r3router:new(routes)

The routes is a array table, like { {...}, {...}, {...} }, Each element in the array is a route, which is a hash table.

The attributes of each element may contain these: * path: client request uri. * handler: Lua callback function. * host: optional, client request host, not only supports normal domain name, but also supports wildcard name, both foo.com and *.foo.com are valid. * remote_addr: optional, client remote address like 192.168.1.100, and we can use CIDR format, eg 192.168.1.0/24. * methods: optional, It's an array table, we can put one or more method names together. Here is the valid method name: "GET", "POST", "PUT", "DELETE", "PATCH", "HEAD", "OPTIONS".

Example:

-- foo handler
function foo(params)
    ngx.say("foo: ", require("cjson").encode(params))
end

local r3route = require "resty.r3"
local r3 = r3route.new({
        {
            path = [[/foo/{:\w+}/{:\w+}"]],
            method = {"GET"},
            handler = foo
        },
        {
            path = [[/bar/{:\w+}/{:\w+}]],
            host = "*.bar.com",
            handler = foo
        },
        {
            path = [[/alice/{:\w+}/{:\w+}]],
            remote_addr = "192.168.1.0/24",
            handler = foo
        },
        {
            path = [[/bob/{:\w+}/{:\w+}]],
            method = {"GET"},
            host = "*.bob.com",
            remote_addr = "192.168.1.0/24",
            handler = foo
        },
    })

insert_route

syntax: r3, err = r3:insert_route(path, callback, opts)

• path: Client request uri.
• callback: Lua callback function.

opts is optional argument, it is a Lua table. * method: It's an array table, we can put one or more method names together. * host: optional, client request host, not only supports normal domain name, but also supports wildcard name, both foo.com and *.foo.com are valid. * remote_addr: optional, client remote address like 192.168.1.100, and we can use CIDR format, eg 192.168.1.0/24.

-- route
local function foo(params)
    ngx.say("foo")
end

local r3route = require "resty.r3"
local r3 = r3route.new()

r3:insert_route("/a", foo)
r3:insert_route("/b", foo, {method = {"GET"}})

add router

BTW, we can add a router by specifying a lowercase method name.

Valid method name list: get, post, put, delete, patch, head, options.

-- route
local function foo(params)
    ngx.say("foo")
end

r3:get("/a", foo)
r3:post("/b", foo)
r3:put("/c", foo)
r3:delete("/d", foo)

compile

syntax: r3:compile()

It compiles our route paths into a prefix tree (trie). You must compile after adding all routes, otherwise it may fail to match.

dispatch

syntax: ok = r3:dispatch(path, method)

• path: client request uri.
• method: method name of client request.

syntax: ok = r3:dispatch(path, opts)

• path: client request uri.
• opts: a Lua tale
  • method: optional, method name of client request.
  • host: optional, client request host, not only supports normal domain name, but also supports wildcard name, both foo.com and *.foo.com are valid.
  • remote_addr: optional, client remote address like 192.168.1.100, and we can use CIDR format, eg 192.168.1.0/24.

Dispatchs the path to the controller by method, path and host.

local ok = r3:dispatch(ngx.var.uri, ngx.req.get_method())

dispatch2

syntax: ok = r3:dispatch2(param_tab, path, method)

syntax: ok = r3:dispatch2(param_tab, path, opts)

Basically the same as dispatch, support for passing in a table object to store parsing parameters, makes it easier to reuse lua table.

Ubuntu

sudo apt-get install check libpcre3 libpcre3-dev build-essential libtool \ automake autoconf pkg-config

CentOS 7

sodu yum install gcc gcc-c++ git make automake autoconf pcre pcre-devel \ libtool pkgconfig

### Compile and install

sudo make install ```

GitHub

You may find additional configuration tips and documentation for this module in the GitHub repository for nginx-module-libr3.