How to test JSON result from Ruby on Rails functional tests?

How can I assert my Ajax request and test the JSON output from Ruby on Rails functional tests?

Solution 1:

In Rails >= 5

Use ActionDispatch::TestResponse#parsed_body.

Example:

user = @response.parsed_body
assert_equal "Mike", user['name']

In Rails up to 4.x

Use JSON.parse, which takes a string as input and returns a Ruby hash that the JSON represents.

Example:

user = JSON.parse(@response.body)
assert_equal "Mike", user['name']

Solution 2:

Rails has JSON support built in:

def json_response
    ActiveSupport::JSON.decode @response.body
end

No need for a plugin

Then you can do something like this:

assert_equal "Mike", json_response['name']

Solution 3:

If you are using RSpec, json_spec is worth a look

https://github.com/collectiveidea/json_spec