to_param incorrectly returns nil for an unpersisted object

[jcoyne]

On an ActiveRecord model (see User below), calling to_param on an unsaved object returns it's key. This is part of ActiveRecord::Integration however on Elasticsearch::Persistence::Model calling to_param on an unsaved object returns nil. It would be nice if Elasticsearch::Persistence::Model matched the behavior of ActiveRecord::Integration: https://github.com/rails/rails/blob/master/activerecord/lib/active_record/integration.rb#L49-L52

class Document
    include Elasticsearch::Persistence::Model
end

class User < ActiveRecord::Base
end


Document.new(id:'123').to_param
nil
> u.to_param
"123"
> User.new(id: '123').to_param
"123"
> Document.new(id:'123').method(:to_param).source_location
["/Users/jcoyne/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activemodel-5.2.0/lib/active_model/conversion.rb", 82]
> User.new(id:'123').method(:to_param).source_location
["/Users/jcoyne/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activerecord-5.2.0/lib/active_record/integration.rb", 49]

[estolfo]

Hi @jcoyne

I'm sorry you're running into this inconsistency between ActiveRecord::Base and Elasticsearch::Persistence's implementation of the ActiveRecord pattern.

Typically, we would work to fix bugs in the elasticsearch gems but we have plans to deprecate the ActiveRecord pattern (Elasticsearch::Persistence::Model) in the next major version, 6.0.

I recommend checking out the Repository pattern in the Elasticsearch::Persistence gem, as we will focus our future development efforts there.

If you don't mind, I'd like to close this issue as it's unlikely we will work on it. Thanks for your understanding.
Emily

[estolfo]

Hi @jcoyne, I'm going to close this issue. Please open a new one if you have further questions. Thanks

[jcoyne]

I am using the repository pattern. But I’d still like the to_param to behave consistently in order to use the rails route helpers.

[estolfo]

Hi @jcoyne, in your example above, you've included the Elasticsearch::Persistence::Model module so can you please provide an example using the Repository pattern and what the expected behavior is? I'm reopening this issue so we can continue looking into it. Thanks!

[jcoyne]

Sure. I'm retrieving an object like this:

repo = Elasticsearch::Persistence::Repository.new do
         klass Document
       end
@doc = repo.find(id)

Now, when I want to route to a controller to handle that document using the rails routing helpers I am doing:

  <%= link_to 'More info', @doc %>

In order to do that latter part, you need to include Elasticsearch::Persistence::Model on Document so that Document will respond to to_param, right?

[estolfo]

@jcoyne You can also define the #to_param method yourself on the model (Document) to return the id. Would that be a solution for you?

[estolfo]

@jcoyne I just wanted to check in and see if you could define #to_param on the model?

[jcoyne]

Yeah, I can add all that ActiveModel stuff myself. Thanks for following up.