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core: New FFI-based API for lua-nginx-module

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-core

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

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

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

This document describes lua-resty-core v0.1.27 released on Jun 19 2023.

lua-resty-core - New FFI-based Lua API for ngx_http_lua_module and/or ngx_stream_lua_module

Status

This library is production ready.

Synopsis

This library is automatically loaded by default in OpenResty 1.15.8.1. This behavior can be disabled via the lua_load_resty_core directive, but note that the use of this library is vividly recommended, as its FFI implementation is both faster, safer, and more complete than the Lua C API of the ngx_lua module.

If you are using an older version of OpenResty, you must load this library like so:

    # nginx.conf

    http {
        # you do NOT need to configure the following line when you
        # are using the OpenResty bundle 1.4.3.9+.
        init_by_lua_block {
            require "resty.core"
            collectgarbage("collect")  -- just to collect any garbage
        }

        ...
    }

Description

This pure Lua library reimplements part of the ngx_lua module's Nginx API for Lua with LuaJIT FFI and installs the new FFI-based Lua API into the ngx. and ndk. namespaces used by the ngx_lua module.

In addition, this Lua library implements any significant new Lua APIs of the ngx_lua module as proper Lua modules, like ngx.semaphore and ngx.balancer.

The FFI-based Lua API can work with LuaJIT's JIT compiler. ngx_lua's default API is based on the standard Lua C API, which will never be JIT compiled and the user Lua code is always interpreted (slowly).

Support for the new ngx_stream_lua_module has also begun.

This library is shipped with the OpenResty bundle by default. So you do not really need to worry about the dependencies and requirements.

Prerequisites

WARNING This library is included with every OpenResty release. You should use the bundled version of this library in the particular OpenResty release you are using. Otherwise you may run into serious compatibility issues.

API Implemented

resty.core.hash

resty.core.base64

resty.core.uri

resty.core.regex

resty.core.exit

resty.core.shdict

resty.core.var

resty.core.ctx

get_ctx_table

syntax: ctx = resty.core.ctx.get_ctx_table(ctx?)

Similar to ngx.ctx but it accepts an optional ctx argument. It will use the ctx from caller instead of creating a new table when the ctx table does not exist.

Notice: the ctx table will be used in the current request's whole life cycle. Please be very careful when you try to reuse the ctx table. You need to make sure there is no Lua code using or going to use the ctx table in the current request before you reusing the ctx table in some other place.

resty.core.request

resty.core.response

resty.core.misc

resty.core.time

resty.core.worker

resty.core.phase

resty.core.ndk

resty.core.socket

resty.core.param

ngx.semaphore

This Lua module implements a semaphore API for efficient "light thread" synchronization, which can work across different requests (but not across nginx worker processes).

See the documentation for this Lua module for more details.

ngx.balancer

This Lua module implements for defining dynamic upstream balancers in Lua.

See the documentation for this Lua module for more details.

ngx.ssl

This Lua module provides a Lua API for controlling SSL certificates, private keys, SSL protocol versions, and etc in NGINX downstream SSL handshakes.

See the documentation for this Lua module for more details.

ngx.ssl.clienthello

This Lua module provides a Lua API for post-processing SSL client hello message for NGINX downstream SSL connections.

See the documentation for this Lua module for more details.

ngx.ssl.session

This Lua module provides a Lua API for manipulating SSL session data and IDs for NGINX downstream SSL connections.

See the documentation for this Lua module for more details.

ngx.re

This Lua module provides a Lua API which implements convenience utilities for the ngx.re API.

See the documentation for this Lua module for more details.

ngx.resp

This Lua module provides Lua API which could be used to handle HTTP response.

See the documentation for this Lua module for more details.

ngx.pipe

This module provides a Lua API to spawn processes and communicate with them in a non-blocking fashion.

See the documentation for this Lua module for more details.

This module was first introduced in lua-resty-core v0.1.16.

ngx.process

This Lua module is used to manage the nginx process in Lua.

See the documentation for this Lua module for more details.

This module was first introduced in lua-resty-core v0.1.12.

ngx.errlog

This Lua module provides Lua API to capture and manage nginx error log messages.

See the documentation for this Lua module for more details.

This module was first introduced in lua-resty-core v0.1.12.

ngx.base64

This Lua module provides Lua API to urlsafe base64 encode/decode.

See the documentation for this Lua module for more details.

This module was first introduced in lua-resty-core v0.1.14.

Caveat

If the user Lua code is not JIT compiled, then use of this library may lead to performance drop in interpreted mode. You will only observe speedup when you get a good part of your user Lua code JIT compiled.

TODO

  • Re-implement ngx_lua's cosocket API with FFI.
  • Re-implement ngx_lua's ngx.eof and ngx.flush API functions with FFI.

See Also

GitHub

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