Omitting Fields

Sometimes you want a field present, other times you don’t. This is often the case when you want to skip fields which have null or empty values.

FakerMaker.factory :user do
  name {'Patsy Stone'}
  email(omit: :nil) {'[email protected]'}
  admin {false}
end

FM[:user].build.as_json
=> {:name=>"Patsy Stone", :email=>"[email protected]", :admin=>false}

FM[:user].build( attributes: { email: nil } ).as_json
=> {:name=>"Patsy Stone", :admin=>false}

The omit modifier can take a single value or an array. If it is passed a value and the attribute equals this value, it will not be included in the output from as_json (which returns a Ruby Hash) or in to_json methods.

There are four special modifiers:

• :nil (symbol) to omit output when the attribute is set to nil.
• :empty to omit output when the value is an empty string, an empty array or an empty hash.
• :always to never output this attribute.
• FakerMaker::OMIT to omit output only when the attribute is set to this token value.

These can be mixed with real values, e.g.

FakerMaker.factory :user do
  name {'Patsy Stone'}
  email(omit: [:nil, :empty, '[email protected]']) {'[email protected]'}
  admin {false}
end

Using the omit token

You may want to exclude a field but still allow it to be set to nil, an empty string/array/hash, or any other value.

FakerMaker::OMIT is a token value that can provide this flexibility, e.g.

FakerMaker.factory :user do
  name(omit: FakerMaker::OMIT) {'Patsy Stone'}
  email(omit: :nil) {'[email protected]'}
  admin(omit: :empty) {false}
end

FM[:user].build( attributes: { name: FakerMaker::OMIT } ).as_json
=> {:email=>"[email protected]", :admin=>false}

FM[:user].build( attributes: { name: nil, email: nil } ).as_json
=> {:name=>nil, :admin=>false}

FM[:user].build( attributes: { name: '', admin: '' } ).as_json
=> {:name=>"", :email=>"[email protected]"}