Kong Plugin Development

Plugin Development Guide

https://docs.konghq.com/2.0.x/plugin-development/

File Structure

<plugin-name>
├── INSTALL.txt
├── README.md
├── kong
│   └── plugins
│       └── <plugin-name>
│           ├── handler.lua
│           └── schema.lua
└── <plugin-name>-<version>.rockspec

schema.lua

Property name	Lua type
name	string
fields	table
entity_checks	function

local typedefs = require "kong.db.schema.typedefs"

return {
  name = "<plugin-name>",
  fields = {
    {
      -- this plugin will only be applied to Services or Routes
      consumer = typedefs.no_consumer
    },
    {
      -- this plugin will only run within Nginx HTTP module
      protocols = typedefs.protocols_http
    },
    {
      config = {
        type = "record",
        fields = {
          -- Describe your plugin's configuration's schema here.        
        },
      },
    },
  },
  entity_checks = {
    -- Describe your plugin's entity validation rules
  },
}

handler.lua

Function name
:init_worker()
:certificate()
:rewrite()
:access()
:header_filter()
:body_filter()
:log()

local BasePlugin = require "kong.plugins.base_plugin"

-- The actual logic is implemented in those modules
local access = require "kong.plugins.my-custom-plugin.access"
local body_filter = require "kong.plugins.my-custom-plugin.body_filter"

local CustomHandler = BasePlugin:extend()

CustomHandler.VERSION  = "1.0.0"
CustomHandler.PRIORITY = 10 

function CustomHandler:new()
  CustomHandler.super.new(self, "my-custom-plugin")
end

function CustomHandler:access(config)
  CustomHandler.super.access(self)

  -- Execute any function from the module loaded in `access`,
  -- for example, `execute()` and passing it the plugin's configuration.
  access.execute(config)
end

function CustomHandler:body_filter(config)
  CustomHandler.super.body_filter(self)

  -- Execute any function from the module loaded in `body_filter`,
  -- for example, `execute()` and passing it the plugin's configuration.
  body_filter.execute(config)
end

return CustomHandler

Installing the plugin

$ cd <plugin-name>
$ luarocks make

Load the plugin

$ vi /etc/kong/kong.conf
plugins = bundled,<plugin-name>
$ kong restart

Verify loading the plugin

$ vi /etc/kong/kong.conf
log_level = debug
$ tail -f /usr/local/kong/logs/error.log

Plugin Development Kit

https://docs.konghq.com/2.0.x/pdk/

• kong.client
• kong.ctx
• kong.ip
• kong.log
• kong.nginx
• kong.node
• kong.request
• kong.response
• kong.router
• kong.service
• kong.service.request
• kong.service.response
• kong.table

참고자료

• https://openresty-reference.readthedocs.io/en/latest/Lua_Nginx_API/
• https://luarocks.org/modules/cdbattags/lua-resty-jwt

  • https://github.com/Kong/kong-vagrant --> https://github.com/Kong/kong-plugin
  • https://github.com/Kong?tab=repositories&q=kong-plugin
  • https://github.com/wshirey?tab=repositories&q=kong-plugin
  • https://github.com/Kong/kong/tree/master/kong/plugins

• https://github.com/luarocks/luarocks/wiki/Rockspec-format