Testing - Learning Chef - page 346

describe '<entity>' do
it '<description>'
expect( resource ).to matcher matcher_parameter
end
end
A resource (also known as a subject or command ) is the first argument for an expect block,
and it expresses the “thing” to be tested. Testing frameworks such as Serverspec and
ChefSpec supply custom resource class implementations that perform a wide variety of
checks.
A matcher is used to define positive or negative expectations on a resource, via the ex-
pect(…).to and expect(…).not_to forms, respectively. These are also supplied as custom
class implementations in testing frameworks.
In Example 16-4 , we used the port resource and the be_listening matcher with the para-
meter tcp to check to see if the website is listening on port 80 over TCP:
describe 'web site' do
it 'responsponds on port 80' do
expect(port 80).to be_listening 'tcp'
end
end
How did we know about this port resource and the be_listening matcher? We referred to
the Serverspec test framework documentation listing the resource and matcher classes it
provides. See the Serverspec documentation . As of this writing, click on the Resource Types
link at the top of the page, and you will see links to all the Serverspec custom resources, as
shown in Figure 16-7 .