How to define helper methods for manipulating the Puppet catalogue object

Question

I have a bunch of repeated code that manipulates the Puppet catalogue object (notice the repeated content = lines):

require 'nokogiri'

describe 'role::jenkins' do
  before(:each) do
    @jobs = catalogue.resource_keys.select{|k,v| k == 'Jenkins::Jobs'}.map{|k,v| v}
  end

  it 'Jenkins jobs should be valid XML' do
    @jobs.each do |j|
      content = catalogue.resource('file', "/tmp/#{j}.xml").send(:parameters)[:content]
      result = Nokogiri::XML(content).errors.empty?
      if ! result
        puts "    Job #{j} does NOT have valid XML"
      end
      expect(result).to be true
    end
  end 

  it "XML should contain a variables.json snippet that is valid JSON" do
    @jobs.each do |j|
      content = catalogue.resource('file', "/tmp/#{j}.xml").send(:parameters)[:content]
      if content.match(/cat &lt;&lt; EOF &gt; #{json_file}.*?EOF/m)
        json_snippet = content.match(/#{json_file}(.*?)EOF/m)[1]
        expect { JSON.parse(json_snippet) }.to_not raise_error
      end
    end
  end
end

As can be seen, I have moved a long query into a before(:each) block and saved it in an instance variable. That makes it available in the it blocks.

What I do not understand is how I could define a method for the content = lines, like:

def content(file_name)
  catalogue.resource('file', file_name).send(:parameters)[:content]
end

If I knew how to do that I could clean up this code considerably. What I cannot figure out is where I could place this def block, if it is even possible to do this.

This actually seems like a pure RSpec question since there are not extended matchers. Is that method of mocking a resource actually working? I thought that was only an experimental feature of that one rspec-puppet helper gem. — Matthew Schuchard, May 07 '17 at 22:02
It definitely works. It is useful to know this trick, and undocumented I think. I could be wrong but my understanding is that the 'catalogue' object (note the UK spelling, whereas US spelling 'catalog' is used elsewhere) is made available by rspec-puppet. — Alex Harvey, May 08 '17 at 00:48
Fair enough. Puppet does actually use `catalog` in its source code for that object just like you said. I probably should dig into this some. Thanks for the info! — Matthew Schuchard, May 08 '17 at 02:04

score 0 · Accepted Answer · answered May 07 '17 at 08:05

I have made a silly mistake (thought I had already tried something when actually I had not).

The answer is just put the def inside the before block as well:

require 'nokogiri'

describe 'role::jenkins' do
  before(:each) do
    @jobs = catalogue.resource_keys.select{|k,v| k == 'Jenkins::Jobs'}.map{|k,v| v}

    def content(file_name)
      catalogue.resource('file', file_name).send(:parameters)[:content]
    end
  end

  it 'Jenkins jobs should be valid XML' do
    @jobs.each do |j|
      result = Nokogiri::XML(content("/tmp/#{j}.xml").errors.empty?
      if ! result
        puts "    Job #{j} does NOT have valid XML"
      end
      expect(result).to be true
    end
  end 

  it 'XML should contain a variables.json snippet that is valid JSON' do
    @jobs.each do |j|
      content = content("/tmp/#{j}.xml")
      if content.match(/cat &lt;&lt; EOF &gt; #{json_file}.*?EOF/m)
        json_snippet = content.match(/#{json_file}(.*?)EOF/m)[1]
        expect { JSON.parse(json_snippet) }.to_not raise_error
      end
    end
  end
end

Please let me know though if anyone can see any further improvements that could be made!

How to define helper methods for manipulating the Puppet catalogue object

1 Answers1