undefined local variable or method `request' - ruby-on-rails

Question

I am new to ruby on rails. I am getting an undefined method error when I run rspec on comment_spec.rb
1) after_save calls 'Post#update_rank' after save
Failure/Error: request.env["HTTP_REFERER"] = '/'
NameError:
undefined local variable or method `request' for #<RSpec::ExampleGroups::AfterSave:0x007fa866ead8d0>
# ./spec/models/vote_spec.rb:45:in `block (2 levels) in <top (required)>'
This is my spec:
require 'rails_helper'
describe Vote do
....
describe 'after_save' do
it "calls 'Post#update_rank' after save" do
request.env["HTTP_REFERER"] = '/'
#user = create(:user)
#post = create(:post, user: #user)
sign_in #user
vote = Vote.new(value:1, post: post)
expect(post). to receive(:update_rank)
vote.save
end
end
Any help that you would have would be greatly appreciated...

Answer 1

I was following the apirails book tutorial chapter 3 here
http://apionrails.icalialabs.com/book/chapter_three
I was receiving the same error and DrPositron's solution worked for me, all green again. Just needed to add ":type => :controller" on my block like so:
describe Api::V1::UsersController, :type => :controller do
end
Hope this helps someone

Answer 2

OK here's the deal.
Vote is a model, i suppose.
You are writing a test for that model.
There's a difference between model tests ("the domain logic is doing what its supposed to") and feature/integration tests ("the application is behaving the way its supposed to").
The request variable is associated with feature or controller tests.
So what's wrong?
You are not logging in users in model tests, just check if the update_rank method is being called on save, thats it.
No user-interaction jazz in model tests.
Hope that helps!
Cheers
Jan

Answer 3

So Louis, just to expand on Jan's response:
You appear to be writing a model spec. The purpose of a model spec is simply to test how your model classes work, and that behavior is testable without having to pay any attention to the application logic around signing in, making "requests" to particular controllers, or visiting particular pages.
You're essentially just testing a couple related Ruby classes. For this, we don't need to think about the whole app -- just the classes we're testing.
As a consequence, RSpec doesn't make certain methods available in the spec/models directory -- you're not supposed to think about requests or authentication in these tests.
It looks like your test is simply designed to make sure that when you create a vote for a post, it updates that post's rank (or, specifically, call's that post's update_rank method). To do that, you don't need to create a user, or sign a user in, or pay any attention to the request (what request would we be referring to? We're just testing this as if in Rails console, with no HTTP request involved).
So you could basically remove the first four lines of your test -- apart from the line creating your post, and the post's user if it's necessary (if the post model validates the presence of a user). Don't sign a user in -- we're just testing a Ruby class. There's no concept of a website to sign into in this test.
Then, as a last thing to take care of to get your spec to pass, make sure to refer to the post you create by the right name. Right now, you're creating a post and assigning it to the #post variable, but then you're referring to just post later on. post doesn't exist; just #post. You'll have to pick one variable name and stick with it.

Answer 4

Also, if you are using RSpec 3, file type inference is now disabled by default and must be opted in as described here. If you're new to RSpec, a quick overview of the canonical directory structure is here.
For example, for a controller spec for RelationshipsController, insert , :type => :controller as such:
describe RelationshipsController, :type => :controller do
#spec
end