atonie.org

How To Test The Atom Protocol Exerciser

The APE is a tool to test AtomPub servers, as defined into RFC5023 Saddly, the APE itself isn't tested. Here are some though on how that could be fixed.

What ?

We should test every test_* methods. Let's take test_entry_posts(entry_collection) as an example. This methods checks that (more or less) :

After a POST :-

• the POST request is successful
• the posted entries appears into the collection/feed
• there is a valid Location header in the response
• check that the newly entry is GETable
• the returned entry is well-formed
• the client-provided Slug header is used into the server generated URIs
• the entry has an edit link

After a PUT :-

• the entry is still presents into the collection
• the title have been updated
• the PUT request is successful

After a DELETE :-

• The entry is not into the collection

The methods also set a lot of message: good, info, warning, depending on the result of the test. Those messages should also be tested.

How ?

We need an AtomPub server whose behaviour could be modified on the fly. I see two possible solution to achieve that: -

1. Implement a dumb AtomPub server using any lightweight Ruby web framework like Camping or Rack. However it may result in slow test execution.

2. Mock it. Create an object responding to all the HTTP verbs. To achieve that, we'd need to be able to pass an object to APE which would be used to perform HTTP operations. Ape::Invoker ?

Example

Here is some code to illustrate the general idea :

describe 'The APE' do
      describe 'when testing entry posting' do
        before(:each) do
          @server = AtomPubServerMock.new
          @ape = APE.new
        end
    
        it "should set an error if the request isn't successful" do
          @server.unsuccessful_post_request!
          @ape.should_receive(:error).with("Can't POST new entry: 500") 
          @ape.check(@server)
        end 
    
        # More sexy
        it "should set an error if the request isn't successful" do
          ape_test(:unsuccessful_post_request!) do
            @ape.should_receive(:error).with("Can't POST new entry: 500")
          end
        end
    
        it 'should set an error if the returned entry is not well-formed' do
          @server.return_malformed_entry!
          @ape.should_receive(:error).with('New entry is not well-formed: foo')
          @ape.check(@server)
        end
    
        describe 'Location header testing' do
          it "should set an error if the Location header isn't present in response" do
            ape_test(:no_location_header!) do
              @ape.should_receive(:error).with("No Location header upon POST creation")
            end
          end
    
          it "should set an 'ok message' if the Location header is present" do
            ape_test do
              @ape.should_receive(:good).with("Posting of new entry to the Entries collection " +
                "reported success, Location: #{@server.location}")
            end
          end
        end
      end
    end