在网上找了好长时间, 居然都没有一个完整的手顺可以写一个kong api gateway 的自定义plugin , 有的都是一些解释和片段
所以只能自己动手查官方文档了, 下面这个例子是我自己按照官方文档整理的, 因为lua脚本和相关api都不是很熟, 所以最后内容方面只写了一个空的
关于目录结构:
目录结构是这种, 下面两个是必须有的module, 我假设你跟我一样没有太多的lua背景知识, handler.lua 和 schema.lua 是两个module的名字, 也是两个文件, 文件夹是 simple-plugin
复杂一点的可能像这样
关于如何加入自己plugin:
在/etc/kong/kong.conf文件中你可以找到下面这段
plugins = bundled
plugins = bundled,my-custom-plugin # your plugin name here
自定义插件的命名个规则为 kong.plugins.<plugin_name>.<module_name>
也就是说当你在plugins属性后面添加了你自己的plugin name之后, kong会尝试加载以kong.plugins.my-custom-plugin.<module_name>命名的lua模块
还记得一开始提到的两个必要模块名么, 所以你的模块应该类似 kong.plugins.my-custom-plugin.handler
关于kong到哪里加载这些文件:
还是/etc/kong/kong.conf, 其中属性 lua_package_path 可以用来指定存放自定义插件的路径
官方文档中这样描述这个配置
也就是说如果你配置
lua_package_path = /usr/local/custom/?.lua;;
那么你的handler.lua文件要放在
/usr/local/custom/kong/plugins/<plugin-name>/handler.lua
下面是一个完整例子, 不过这个例子里的plugin是空的, 什么都没做, 我将对应着上面的内容写
关于目录结构:
我只使用了两个文件 ( 文件内容最后再发 )
/shared/kongplugins/kong/plugins/my-custom-plugin/handler.lua
/shared/kongplugins/kong/plugins/my-custom-plugin/schema.lua
关于如何加入自己plugin:
在/etc/kong/kong.conf文件中加入对应的模块名
plugins = bundled,my-custom-plugin
关于kong到哪里加载这些文件:
在/etc/kong/kong.conf文件中加入对应的模块存放文件夹路径
lua_package_path = ./?.lua;./?/init.lua;/shared/kongplugins/?.lua;
最后把kong启动起来, 添加一个global的自定义插件吧
[root@localhost ~]# kong start
2018/11/23 10:42:57 [warn] ulimit is currently set to "1024". For better performance set it to at least "4096" using "ulimit -n"
Kong started
[root@localhost ~]# curl -X POST http://localhost:8001/plugins -d "name=my-custom-plugin"
{"created_at":1542966253000,"config":{},"id":"1029886c-6c18-4d98-9e4d-8565ec47c41e","enabled":true,"name":"my-custom-plugin"}
打开dashboard可以看到
schema.lua文件
return {
no_consumer = true,
fields = {
}
}handler.lua文件
-- Extending the Base Plugin handler is optional, as there is no real
-- concept of interface in Lua, but the Base Plugin handler's methods
-- can be called from your child implementation and will print logs
-- in your `error.log` file (where all logs are printed).
local BasePlugin = require "kong.plugins.base_plugin"
local CustomHandler = BasePlugin:extend()
-- Your plugin handler's constructor. If you are extending the
-- Base Plugin handler, it's only role is to instantiate itself
-- with a name. The name is your plugin name as it will be printed in the logs.
function CustomHandler:new()
CustomHandler.super.new(self, "my-custom-plugin")
end
function CustomHandler:init_worker()
-- Eventually, execute the parent implementation
-- (will log that your plugin is entering this context)
CustomHandler.super.init_worker(self)
-- Implement any custom logic here
end
function CustomHandler:certificate(config)
-- Eventually, execute the parent implementation
-- (will log that your plugin is entering this context)
CustomHandler.super.certificate(self)
-- Implement any custom logic here
end
function CustomHandler:rewrite(config)
-- Eventually, execute the parent implementation
-- (will log that your plugin is entering this context)
CustomHandler.super.rewrite(self)
-- Implement any custom logic here
end
function CustomHandler:access(config)
-- Eventually, execute the parent implementation
-- (will log that your plugin is entering this context)
CustomHandler.super.access(self)
-- Implement any custom logic here
end
function CustomHandler:header_filter(config)
-- Eventually, execute the parent implementation
-- (will log that your plugin is entering this context)
CustomHandler.super.header_filter(self)
-- Implement any custom logic here
end
function CustomHandler:body_filter(config)
-- Eventually, execute the parent implementation
-- (will log that your plugin is entering this context)
CustomHandler.super.body_filter(self)
-- Implement any custom logic here
end
function CustomHandler:log(config)
-- Eventually, execute the parent implementation
-- (will log that your plugin is entering this context)
CustomHandler.super.log(self)
-- Implement any custom logic here
end
-- This module needs to return the created table, so that Kong
-- can execute those functions.
return CustomHandler
