Extend lua-resty-* modules and call parent function

boby · 2015-07-29T01:22:35+00:00

Well, you can just add the following stub access_by_lua return; Simple and effective.Thks.

Extend lua-resty-* modules and call parent function

boby

Hello,

I am trying to write for each , and modules a small class that extends the default module. In my child class, I want to call a function from the parent class but couldn't find a proper way no matter what inheritance documentation for Lua I've read.

For example, I want to overwrite the connect() function, do some stuff and call the parent's connect() function at some point. But how?

local redis = require "resty.redis"

function redis.connect(self, ...)

  -- Do some stuff here

  local ok, err = parent:connect(...)

  -- Do some other stuff here

  return ok, err
end

How can this be achieved?

Thank you in advance!

brian

You can maybe do something like:

local redis = require "resty.redis"

local _M = {}

local mt = { __index = _M }

function _M.new()

return setmetatable({ _parent = redis.new()}, mt)

end

function _M.connect(self)

.. do something with self

local ok, err = self._parent:connect()

...

end

You'd need to "wrap" each function. You could probably do a little metatable indirection to call other functions in the "parent" without having to override each call.

On Tue, Jul 28, 2015 at 1:22 PM, Constantin Bejenaru <b...@frozenminds.com> wrote:

Hello,

I am trying to write for each , and modules a small class that extends the default module. In my child class, I want to call a function from the parent class but couldn't find a proper way no matter what inheritance documentation for Lua I've read.

For example, I want to overwrite the connect() function, do some stuff and call the parent's connect() function at some point. But how?

local redis = require "resty.redis" function redis.connect(self, ...) -- Do some stuff here local ok, err = parent:connect(...) -- Do some other stuff here return ok, err end

How can this be achieved?

Thank you in advance!

.