Ruby TestUnit, VCR and HTTP API Requests

Question

I am building an API wrapper and am writing some tests for it and I have a couple of questions.

1) How do I write an assert for calls where data doesn't exist? For example, looking up a member by id using the API but the user won't exist yet.
2) How do I write an assert for testing PUT and DELETE requests?

I already have a grasp on testing GET and POST requests just not sure on the other 2 verbs.

Answer 1

For your question part 1...

You have a couple choices for data that doesn't exist:

1. You can create the data ahead of time, for example by using a test seed file, or a fixture, or a factory. I like this choice for larger projects with more sophisticated data arrangements. I also like this choice for getting things working first because it's more straightfoward to see the data.

2. You can create a test double, such as a stub method or fake object. I like this choice for fastest test performance and best isolation. For fastest tests, I intercept calls as early as possible. The tradeoff is that I'm not doing end-to-end testing.

For your question part 2...

You should edit your question to show your actual code; this will help people here answer you.

Is your VCR code is something like this?

VCR.use_cassette('test_unit_example') do
  response = Net::HTTP.get_response('localhost', '/', 7777)
  assert_equal "Hello", response.body
end

If so, you change the HTTP get to put, something like this:

uri = URI.parse(...whatever you want...)
json = "...whatever you want..."
req = Net::HTTP::Put.new(uri)
req["content-type"] = "application/json"
req.body = json
request(req)

Same for HTTP delete:

Net::HTTP::Delete.new(uri)

A good blog post is the http://www.rubyinside.com/nethttp-cheat-sheet-2940.html>Net::HTTP cheat sheet excerpted here:

# Basic REST.
# Most REST APIs will set semantic values in response.body and response.code.
require "net/http"

http = Net::HTTP.new("api.restsite.com")

request = Net::HTTP::Post.new("/users")
request.set_form_data({"users[login]" => "quentin"})
response = http.request(request)
# Use nokogiri, hpricot, etc to parse response.body.

request = Net::HTTP::Get.new("/users/1")
response = http.request(request)
# As with POST, the data is in response.body.

request = Net::HTTP::Put.new("/users/1")
request.set_form_data({"users[login]" => "changed"})
response = http.request(request)

request = Net::HTTP::Delete.new("/users/1")
response = http.request(request)