Note: I tried playing with this in ~/Project/rubystuff/railsstuff/my_newer_app/spec/controllers/shout_controller_spec.rb and could not quite get it to work.

How to send raw post data in a Rails functional test?

I’m looking to send raw post data (e.g. unparamaterized json) to one of my controllers for testing: ``

class LegacyOrderUpdateControllerTest < ActionController::TestCase
 test "sending json" do
   post :index, '{"foo":"bar", "bool":true}'

but this gives me a NoMethodError: undefined method symbolize_keys’ for #`

What is the correct way to send raw post data in ActionController::TestCase?

Here is some controller code

def index
    post_data =
    req = JSON.parse(post_data)

7 Answers

I ran across the same issue today and found a solution.

In your test_helper.rb define the following method inside of ActiveSupport::TestCase:

  def raw_post(action, params, body)
    @request.env['RAW_POST_DATA'] = body
    response = post(action, params)

In your functional test, use it just like the post method but pass the raw post body as the third argument.

class LegacyOrderUpdateControllerTest < ActionController::TestCase
 test "sending json" do
   raw_post :index, {}, {:foo => "bar", :bool => true}.to_json

I tested this on Rails 2.3.4 when reading the raw post body using


instead of

If you look at the source code you’ll see that raw_post just wraps with a check for this RAW_POST_DATA in the request env hash.

This approach continues to work correctly in Rails 3.1

Huh, yeah And Rails 3.2 too. Thanks!

Make sure you’re using request.raw_post (as in this answer) instead of request.body when parsing the JSON in your controller, or you’ll get a weird error about “can’t convert StringIO into String”.

This doesn’t work in rails 3.2.10+

I actually solved the same issues just adding one line before simulating the rspec post request. What you do is to populate the “RAW_POST_DATA”. I tried to remove the attributes var on the post :create, but if I do so, it do not find the action.

Here my final solution.

def do_create(attributes)
  request.env['RAW_POST_DATA'] = attributes.to_json
  post :create, attributes

In the controller the code you need to read the JSON is something similar to this

  @property =

great! Just one line, and I had it work even without the attributes sent in to post.

Looking at stack trace running a test you can acquire more control on request preparation: => ActionDispatch::Integration::Session.process => Rack::Test::Session.env_for

You can pass json string as :params AND specify a content type “application/json”. In other case content type will be set to “application/x-www-form-urlencoded” and your json will be parsed properly.

So all you need is to specify “CONTENT_TYPE”:

post :index, '{"foo":"bar", "bool":true}', "CONTENT_TYPE" => 'application/json'

This does not work for me. I get an error like “undefined method `symbolize_keys’ for #<String:0x00000102b4b0d8>”

The post method expects a hash of name-value pairs, so you’ll need to do something like this:

post :index, :data => '{"foo":"bar", "bool":true}'

Then, in your controller, get the data to be parsed like this:

post_data = params[:data]

I’ve tried this, it needs to be completely raw though {“response”:”error”,”errors”:”can’t parse request: 598: unexpected token at ‘data=

If you are using RSpec (>= 2.12.0) and writing Request specs, the module that is included is ActionDispatch::Integration::Runner. If you take a look at the source code you can notice that the post method calls process which accepts a rack_env parameter.

All this means that you can simply do the following in your spec:


post '/articles', {}, {'RAW_POST_DATA' => 'something'}

And in the controller:


def create

Maybe it’s the way you’re formatting your JSON, it might need to be escaped some how? Try doing this:

post :index, :data => {:foo => 'bar', :bool => true }.to_json

This will turn the hash into json, and hopefully that should work. If not… well then I’m all out of ideas =)