Remove 3rd party lua plugin support (#11821)

rootfs/etc/nginx/lua/plugins.lua

@@ -1,61 +0,0 @@
-local require = require
-local ngx = ngx
-local ipairs = ipairs
-local string_format = string.format
-local ngx_log = ngx.log
-local INFO = ngx.INFO
-local ERR = ngx.ERR
-local pcall = pcall
-
-local _M = {}
-local MAX_NUMBER_OF_PLUGINS = 20
-local plugins = {}
-
-local function load_plugin(name)
-  local path = string_format("plugins.%s.main", name)
-
-  local ok, plugin = pcall(require, path)
-  if not ok then
-    ngx_log(ERR, string_format("error loading plugin \"%s\": %s", path, plugin))
-    return
-  end
-  local index = #plugins
-  if (plugin.name == nil or plugin.name == '') then
-    plugin.name = name
-  end
-  plugins[index + 1] = plugin
-end
-
-function _M.init(names)
-  local count = 0
-  for _, name in ipairs(names) do
-    if count >= MAX_NUMBER_OF_PLUGINS then
-      ngx_log(ERR, "the total number of plugins exceed the maximum number: ", MAX_NUMBER_OF_PLUGINS)
-      break
-    end
-    load_plugin(name)
-    count = count + 1 -- ignore loading failure, just count the total
-  end
-end
-
-function _M.run()
-  local phase = ngx.get_phase()
-
-  for _, plugin in ipairs(plugins) do
-    if plugin[phase] then
-      ngx_log(INFO, string_format("running plugin \"%s\" in phase \"%s\"", plugin.name, phase))
-
-      -- TODO: consider sandboxing this, should we?
-      -- probably yes, at least prohibit plugin from accessing env vars etc
-      -- but since the plugins are going to be installed by ingress-nginx
-      -- operator they can be assumed to be safe also
-      local ok, err = pcall(plugin[phase])
-      if not ok then
-        ngx_log(ERR, string_format("error while running plugin \"%s\" in phase \"%s\": %s",
-            plugin.name, phase, err))
-      end
-    end
-  end
-end
-
-return _M

rootfs/etc/nginx/lua/plugins/README.md

@@ -1,36 +0,0 @@
-# Custom Lua plugins
-
-ingress-nginx uses [https://github.com/openresty/lua-nginx-module](https://github.com/openresty/lua-nginx-module) to run custom Lua code
-within Nginx workers. It is recommended to familiarize yourself with that ecosystem before deploying your custom Lua based ingress-nginx plugin.
-
-### Writing a plugin
-
-Every ingress-nginx Lua plugin is expected to have `main.lua` file and all of its dependencies.
-`main.lua` is the entry point of the plugin. The plugin manager uses convention over configuration
-strategy and automatically runs functions defined in `main.lua` in the corresponding Nginx phase based on their name.
-
-Nginx has different [request processing phases](https://nginx.org/en/docs/dev/development_guide.html#http_phases).
-By defining functions with the following names, you can run your custom Lua code in the corresponding Nginx phase:
-
- - `init_worker`: useful for initializing some data per Nginx worker process
- - `rewrite`: useful for modifying request, changing headers, redirection, dropping request, doing authentication etc
- - `header_filter`: this is called when backend response header is received, it is useful for modifying response headers
- - `body_filter`: this is called when response body is received, it is useful for logging response body 
- - `log`: this is called when request processing is completed and a response is delivered to the client
-
-Check this [`hello_world`](https://github.com/kubernetes/ingress-nginx/tree/main/rootfs/etc/nginx/lua/plugins/hello_world) plugin as a simple example or refer to [OpenID Connect integration](https://github.com/ElvinEfendi/ingress-nginx-openidc/tree/master/rootfs/etc/nginx/lua/plugins/openidc) for more advanced usage.
-
-Do not forget to write tests for your plugin.
-
-### Installing a plugin
-
-There are two options:
-
-  - mount your plugin into `/etc/nginx/lua/plugins/<your plugin name>` in the ingress-nginx pod
-  - build your own ingress-nginx image like it is done in the [example](https://github.com/ElvinEfendi/ingress-nginx-openidc/tree/master/rootfs/etc/nginx/lua/plugins/openidc) and install your plugin during image build
-
-Mounting is the quickest option.
-
-### Enabling plugins
-
-Once your plugin is ready you need to use [`plugins` configuration setting](https://kubernetes.github.io/ingress-nginx/user-guide/nginx-configuration/configmap/#plugins) to activate it. Let's say you want to activate `hello_world` and `open_idc` plugins, then you set `plugins` setting to `"hello_world, open_idc"`. _Note_ that the plugins will be executed in the given order.

rootfs/etc/nginx/lua/plugins/hello_world/main.lua

@@ -1,13 +0,0 @@
-local ngx = ngx
-
-local _M = {}
-
-function _M.rewrite()
-  local ua = ngx.var.http_user_agent
-
-  if ua == "hello" then
-    ngx.req.set_header("x-hello-world", "1")
-  end
-end
-
-return _M

rootfs/etc/nginx/lua/plugins/hello_world/test/main_test.lua

@@ -1,24 +0,0 @@
-
-local main = require("plugins.hello_world.main")
-
--- The unit tests are run within a timer phase in a headless Nginx process.
--- Since `set_header` and `ngx.var.http_` API are disabled in this phase we have to stub it 
--- to avoid `API disabled in the current context` error.
-
-describe("main", function()
-  describe("rewrite", function()
-    it("sets x-hello-world header to 1 when user agent is hello", function()
-      ngx.var = { http_user_agent = "hello" }
-      stub(ngx.req, "set_header")
-      main.rewrite()
-      assert.stub(ngx.req.set_header).was_called_with("x-hello-world", "1")
-    end)
-
-    it("does not set x-hello-world header to 1 when user agent is not hello", function()
-      ngx.var = { http_user_agent = "not-hello" }
-      stub(ngx.req, "set_header")
-      main.rewrite()
-      assert.stub(ngx.req.set_header).was_not_called_with("x-hello-world", "1")
-    end)
-  end)
-end)

rootfs/etc/nginx/lua/test/plugins_test.lua

@@ -1,23 +0,0 @@
-describe("plugins", function()
-  describe("#run", function()
-    it("runs the plugins in the given order", function()
-      ngx.get_phase = function() return "rewrite" end
-      local plugins = require("plugins")
-      local called_plugins = {}
-      local plugins_to_mock = {"plugins.pluginfirst.main", "plugins.pluginsecond.main", "plugins.pluginthird.main"}
-      for i=1, 3, 1
-      do
-        package.loaded[plugins_to_mock[i]] = {
-          rewrite = function()
-            called_plugins[#called_plugins + 1] = plugins_to_mock[i]
-          end
-        }
-      end
-      assert.has_no.errors(function()
-        plugins.init({"pluginfirst", "pluginsecond", "pluginthird"})
-      end)
-      assert.has_no.errors(plugins.run)
-      assert.are.same(plugins_to_mock, called_plugins)
-    end)
-  end)
-end)