Replacing render_component

rubyonrails-talk
1

New to Ruby, new to Rails. I've googled much on this topic, but I don't think I have enough knowledge to form the correct queries.

I've been given the task of resurrecting an old Rails app that's not seen the light of day for two years. It seems to rely heavily on render_component which I am given to understand by various error messages is now deprecated, unfashionable, and unfit to be seen with on social occasions.

However, what I haven't found is much on what to do with render_component code to make it more modern, apart from "Components are a special-purpose approach that can often be replaced with better use of partials and filters." Whatever they may be.

Is there anywhere I can go to help me understand what the render_component calls are doing in this particular instance, and how best to refactor them?

2

The render_component was extracted as a plugin, so the documentation here should explain what render_component is actually doing:

http://github.com/rails/render_component/tree/master

I have provided an example here of a refactoring based on what you described below:

http://gist.github.com/159227

HTH, Nicholas

3

Nicholas Henry wrote:

The render_component was extracted as a plugin, so the documentation here should explain what render_component is actually doing:

GitHub - rails/render_component: NOTICE: official repository moved to https://github.com/malev/render_component. Components allow you to call other actions for their rendered response while executing another action

I have provided an example here of a refactoring based on what you described below:

gist:159227 ยท GitHub

HTH, Nicholas

I've had a go at installing the plugin (just to get the thing to work enough I can see what it does) but that just threw up other errors; however, I think the idea of looking through the docs and code is a good one.

The refactoring looks interesting - I'll see if I can wrap my newbie head around it :slight_smile:

Thanks.

4

Yeah, I wouldn't be surprised if the plugin is not compatible with the latest versions of rails. It probably isn't being maintained. If you like the concept of components, you can check out Cells which is an improved version of rendered_component:

http://github.com/apotonick/cells/tree/master

This is an improved version of the concept. I haven't tried it out myself, but have been meaning to.

Cheers, Nicholas

5

I had to do this with my first few rails apps after it turned out that render_component had horrible performance. It was kind of a pain because the first rails books used them in examples and there was no discussion back then about whether or not it was a good idea. Anyway...

a render :partial and a render component in a controller could be replaced by a filter of some sort. That said, it has been a long long time and I might be a bit off there. At anyrate, I had only really used them in views and converting them usually involved just making sure whatever variables they depended on were passed in as locals or already available as instance variables.

Some specific code examples could allow use to make suggestions about how to start re-factoring.