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Virtual Attributes And Rails 5 Attribute API Discussion

General • Asked by Chris Oliver

Nice. I'd love to see an screencast with the ActionCable feature


Videos on how sockets, http, building a web framework, etc... All work would be awesome!!!


First of all, thank you for all the knowledge sharing. Small feedback, though... You spent 27 out of 31 minutes presenting the problem, and only the rest for the solution. I understand the need for context, but I think your videos should be about the solution, not the problem. Happy holidays.


Interested to watch those videos! I'm also interested to watch videos about ActionCable and how to deploy Rails app that has ActionCable to Heroku.

Btw, .to_bool is not built in right? It's from this gem right?


Thank you, Chris!


would definitely like videos on how rails works and web frameworks work - would be super useful!


It would be very interesting to see how rails and web framework works


Hi, web framework from scratch would be super usefull! 20 yrs ago (damn I am old:) I tried to implement my own object oriented "framework" for Borland Pascal as I was unable to learn their TurboVision. After third take I found myself that I was writing a TurboVision clone, stopped and it just clicked in my brain and I was able to use TurboVision :-)


Great video, I enjoyed the discussion.

Also, enjoyed the peek at the underlying rails code - not so scary after all :)



I'm curious if you looked at how a boolean attribute works in an edit form (ie for a persisted record). I have a boolean virtual attribute that controls whether to advance to a file upload form - no need to persist the value in this case, but I do want it to default to false and be available on both edit and new forms.

If you try to render a form for a persisted record with a boolean (I haven't looked into what happens with other types) virtual attribute, you will get a ActiveModel::MissingAttributeError. Unfortunately the default option does not seem to work in this case, so to get around it I had to override the getter for the virtual attribute; I'm not sure if this is a bug in the current implementation or if there's something I'm missing.

Here's my override method (I originally thought I could use check self[:my_attribute] against nil but even that will throw the MissingAttributeError) - obviously the fact that I'm having to use send to access the private #attribute method feels like a code smell to me:

`ruby
def my_attribute
value = send(:attribute, :my_attribute)
if !value
false
else
value
end
end
```


Thank you, man. It helped me a lot!


I don't post so much so first : thanks for the screencast on the site, I find them very valuable :)
I just stumbled upon this screencast, so I know this is an old topic but is there still any plan on this video series about building a web framework ? It would be awesome, either way I found some articles online but if anyone got some resources to point out on this topic I would really enjoy it.


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