How to check if a param is true or false?

Question

This is really racking my brain, but maybe I\'m trying to hard.

I\'m passing a param via a URL (example.com?debug=true)

So I basically want to say:

Answer 1

Since Rails/ActiveRecord 4.2.0 it is

if ActiveRecord::Type::Boolean.new.type_cast_from_user params[:debug]
  do xyz
else
  do abc
end

In Rails 5 it is:

if ActiveModel::Type::Boolean.new.cast params[:debug]
  do xyz
else
  do abc
end

Answer 2

params come in as strings, so you need to compare against "true", not true.

Answer 3

You could use ActiveRecord's method of checking truthful values if you don't want to reinvent the wheel (this is what is used when passing params inside an ActiveRecord object

Rails 3-4.1

if ActiveRecord::ConnectionAdapters::Column.value_to_boolean(params[:debug])
    do xyz
else
    do abc

Rails 4.2.0

ActiveRecord::Type::Boolean.new.type_cast_from_database(params[:debug])

Rails 5

ActiveModel::Type::Boolean.new.cast(params[:debug])

Might be worth wrapping in a helper but never the less it's quite flexible:

rails c
Loading development environment (Rails 3.2.6)
1.9.3p194 :001 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean '1'
 => true 
1.9.3p194 :002 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean '0'
 => false 
1.9.3p194 :003 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean 1
 => true 
1.9.3p194 :004 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean true
 => true 
1.9.3p194 :005 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean 'true'
 => true 
1.9.3p194 :006 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean 'on'
 => true 
1.9.3p194 :007 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean 'off'

Custom extension

Some people frown on extending core classes but this does fit with the DRY principle.

# config/initializer/boolean.rb
class Boolean
  def self.parse(value)
    ActiveRecord::ConnectionAdapters::Column.value_to_boolean(value)
  end
end

Then used like

if Boolean.parse(params[:debug])
  then xyz

Answer 4

But for whatever reason that if statement just isn't doing like it seems like it should.

I can almost guarantee that it is doing exactly what it should. When things don't make sense, one of our assumptions is wrong.

Is the value actually a boolean or is it string (or something else?). If the value is a string then of course the comparison to the boolean value true will fail. Try comparing to 'true' and see if that works.