CODEWITHSUNDEEP
ruby-on-railsruby-on-rails-4activerecordinspect
Andrew Grimm
Andrew Grimm

Reputation: 81641

Inspecting verbose ActiveRecord objects in Rails 4

I'm inspecting an ActiveRecord object in pry and the Rails console, but one of the attributes is really verbose.

my_record.document.to_s.length # => 45480

How can I view the record, telling Rails that I only want a few dozen characters from my_record.document before truncating it with an ellipsis?

Upvotes: 1

Views: 531

Answers (1)

Anthony E
Anthony E

Reputation: 11245

You can use the truncate method from action view to do this. For instance, if you wanted to truncate to 300 characters, including the ellipsis, then you could do the following.

truncate(my_record.document.to_s, length: 300)

You'll first have to include ActionView::Helper methods in order to have truncate available in your console.

include ActionView::Helpers

This is also trivial to do in pure Ruby if you want to go that route:

max_length = 10
"This could be a really long string".first(max_length - 3).ljust(max_length, "...")

outputs:

"This co..."

EDIT

If you want to truncate inspection for a single attribute override the attribute_for_inspect:

For instance, you could truncate display of the document column to 300 characters (including ellipsis) as follows:

In your model:

def attribute_for_inspect(attr_name)
  if attr_name.to_sym == :document
    max_length = 300
    value = read_attribute(attr_name).to_s

    # You should guard against nil here.
    value.first(max_length - 3).ljust(max_length, "...")
  else
    super
  end
end

attr_for_inspect is defined in ActiveRecord::AttributeMethods if you want to see how it works: https://github.com/rails/rails/blob/52ce6ece8c8f74064bb64e0a0b1ddd83092718e1/activerecord/lib/active_record/attribute_methods.rb#L296.

Upvotes: 2

Related Questions