attribute allowlist repro

default_spec.rb

require_relative 'fb_helpers.rb'

describe FB::Helpers do
  context 'filter_hash' do
    it 'returns a passing hash unchanged' do
      hash = {
        'fb_sysctl' => {
          'kernel.core_uses_pid' => 0,
        },
      }
      filter = 'fb_sysctl'
      expect(FB::Helpers.filter_hash(hash, filter)).to eq(hash)
    end

    it 'filters a failing hash' do
      hash = {
        'fb_sysctl' => {
          'kernel.core_uses_pid' => 0,
        },
      }
      expect(FB::Helpers.filter_hash(hash, [])).to eq({})
    end

    it 'returns a passing deep hash unchanged' do
      hash = {
        'fb_network_scripts' => {
          'ifup' => {
            'ethtool' => 'cookie',
          },
        },
      }
      filter = 'fb_network_scripts/ifup/ethtool'
      expect(FB::Helpers.filter_hash(hash, filter)).to eq(hash)
    end

    it 'filters a failing deep hash' do
      hash = {
        'fb_network_scripts' => {
          'ifup' => {
            'extra_commands' => 'cookie',
          },
        },
      }
      filter = 'fb_network_scripts/ifup/ethtool'
      expect(FB::Helpers.filter_hash(hash, filter)).to eq({})
    end

    it 'handles compound hashes and filters' do
      hash = {
        'fb_sysctl' => {
          'kernel.core_uses_pid' => 0,
        },
        'fb_network_scripts' => {
          'ifup' => {
            'ethtool' => 'cookie',
            'boo' => 123,
          },
        },
        'fb_foo' => {
          'bar' => 4,
        },
      }
      filtered_hash = {
        'fb_sysctl' => {
          'kernel.core_uses_pid' => 0,
        },
        'fb_network_scripts' => {
          'ifup' => {
            'ethtool' => 'cookie',
          },
        },
      }
      filter = ['fb_sysctl', 'fb_network_scripts/ifup/ethtool']
      expect(FB::Helpers.filter_hash(hash, filter)).to eq(filtered_hash)
    end

    it 'handles hashes with empty values' do
      hash = {
        'fb_network_scripts' => {
          'ifup' => {
            'extra_commands' => {},
          },
        },
      }

      filter = 'fb_network_scripts/ifup/ethtool'
      expect(FB::Helpers.filter_hash(hash, filter)).to eq(hash)
    end
  end
end

fb_helpers.rb

require 'chef/attribute_allowlist'
require 'chef/log'

module FB
  class Helpers
    def self.filter_hash(hash, filter)
      if filter.is_a?(String)
        filter = [filter]
      elsif !filter.is_a?(Array)
        fail 'fb_helpers: the filter argument to filter_hash needs to be a ' +
          "String or an Array (actual: #{filter.class})"
      end

      Chef::AttributeAllowlist.filter(hash, filter)
    end
  end
end

output.txt

$ rspec default_spec.rb 
...[2020-08-05T13:22:42-07:00] WARN: Could not find whitelist attribute fb_network_scripts/ifup/ethtool.
F.[2020-08-05T13:22:42-07:00] WARN: Could not find whitelist attribute fb_network_scripts/ifup/ethtool.
F

Failures:

  1) FB::Helpers filter_hash filters a failing deep hash
     Failure/Error: expect(FB::Helpers.filter_hash(hash, filter)).to eq({})
     
       expected: {}
            got: {"fb_network_scripts"=>{"ifup"=>{}}}
     
       (compared using ==)
     
       Diff:
       @@ -1 +1,2 @@
       +"fb_network_scripts" => {"ifup"=>{}},
       
     # ./default_spec.rb:62:in `block (3 levels) in <top (required)>'

  2) FB::Helpers filter_hash handles hashes with empty values
     Failure/Error: expect(FB::Helpers.filter_hash(hash, filter)).to eq(hash)
     
       expected: {"fb_network_scripts"=>{"ifup"=>{"extra_commands"=>{}}}}
            got: {"fb_network_scripts"=>{"ifup"=>{}}}
     
       (compared using ==)
     
       Diff:
       @@ -1,2 +1,2 @@
       -"fb_network_scripts" => {"ifup"=>{"extra_commands"=>{}}},
       +"fb_network_scripts" => {"ifup"=>{}},
       
     # ./default_spec.rb:104:in `block (3 levels) in <top (required)>'

Finished in 0.01842 seconds (files took 0.25777 seconds to load)
6 examples, 2 failures

Failed examples:

rspec ./default_spec.rb:53 # FB::Helpers filter_hash filters a failing deep hash
rspec ./default_spec.rb:94 # FB::Helpers filter_hash handles hashes with empty values

$