Extracted attributes assingment from ActiveRecord to ActiveModel

[bogdan]

Now you are able to do:

class Feedback
  include ActiveModel::AttributeAssignment
  attr_accessor :email, :subject, :body
end

f = Feedback.new
f.assign_attributes(
  :email => "bogdan@example.com", 
  :subject => "Hello", 
  :body => "The app dont work for me"
)

This is just a proof of concept PR.

There is still some todos:

• Write tests for ActiveModel::AttributeAssignment
• Deprecate AR::UnknownAttributeError in flavor of AM one
• Add change log entry
• rebase change log entry 2-3 times

I am gonna add them if this will be approved to merge in.

[dmathieu]

I don't think this is still necessary.

[bogdan]

Existing rails apps could still use this constant to catch this exception and process it manually.

[dmathieu]

Raising it has to trigger a deprecation then.

[bogdan]

Do you know how to do that?

[dmathieu]

Is there a reason why you didn't extract the tests too ?

[bogdan]

@dmathieu once I saw someone from core team saying that overlapping between AR and AM tests is good idea. No concrete reason.

[robin850]

Could you please indent the private methods as the contribution guideline states ? Also, I think that this will at least need a changelog entry. Not sure if you should add one in AR changelog as well.

[robin850]

Nice pull request though, thank you!

[rafaelfranca]

What is the motivation for this extraction?

[bogdan]

Using outside of activerecord just like validation and others:

Attributes assignment concept is something I personally use a lot for many types of objects.

[rafaelfranca]

👍 for the idea from my side. @sgrif WDYT?

[sgrif]

👍 for the idea from me, as well. Would like to review the code again once it's been rebased onto master and had tests added/moved/etc

[bogdan]

Updated the PR:

• Rebased with master
• Added tests for ActiveModel
• Decided to keep a separated documentation for #attributes= in activerecord because it includes many DB interaction points
• Left ActiveRecord::AttributeAssignment tests untouched that now creates some overlap in tests. Thought it is a good idea
• Made changelog

[arthurnn]

I would use this on Mongoid if this is merge on ActiveModel.!

[rafaelfranca]

Should not this method be private?

[bogdan]

@rafaelfranca removed all whitespace

[vipulnsward]

AttributesAssignment => AttributeAssignment

[vipulnsward]

same here

[egilburg]

❤️

[egilburg]

I wonder if, once all non-db-specific logic (including recent one such as the user-facing casting half) is extracted to AM, it would make sense to have a more full-featured out-of-the-box implementation of active model for those that want it to behave not just as a form object but as much as a full AR as possible, except not persisted. That means all the same validations/errors, attribute assignment, casting, etc.

Perhaps call it ActiveModel::Base which would be a richer implementation than ActiveModel::Model, possibly extending it.

[egilburg]

Given that end users may be rescuing from this error in their apps, it seems like a rather long and implementation-specific namespace. Perhaps keep it under ActiveModel::UnknownAttributeError?

[robin850]

Yep, I agree there ; this is too implementation-specific! 👍

[sgrif]

Agreed, let's leave this undeprecated, and just alias it. It's an unnecessary change for users, and forces them to care too much about implementation.

[sgrif]

@robin850 Would you care to open a PR?

[bogdan]

Leaving this undeprecated can cause confusion because while constant alias will work the caught exception instances will still have new name. It looks like people are just yelling about too long name space and want it to be sorter like in @egilburg's comment