Class: Hiera::Backend::Mwyaml_backend

Inherits:
Object
  • Object
show all
Defined in:
puppet/modules/wmflib/lib/hiera/backend/mwyaml_backend.rb

Overview

This naming is required by puppet.

Instance Method Summary collapse

Constructor Details

#initialize(cache = nil) ⇒ Mwyaml_backend

Returns a new instance of Mwyaml_backend.



6
7
8
 
# File 'puppet/modules/wmflib/lib/hiera/backend/mwyaml_backend.rb', line 6

def initialize(cache = nil)
  @cache = cache || Mwcache.new
end

Instance Method Details

#lookup(key, scope, order_override, resolution_type) ⇒ Object 



10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
 
# File 'puppet/modules/wmflib/lib/hiera/backend/mwyaml_backend.rb', line 10

def lookup(key, scope, order_override, resolution_type)
  answer = nil
  Hiera.debug("Looking up #{key}")

  Backend.datasources(scope, order_override) do |source|
    # Small hack: We don't want to search any datasource but the
    # labs/%{::labsproject} hierarchy here; so we plainly exit
    # in any other case.
    next unless source.start_with?('labs/') && source.length > 'labs/'.length

    # For hieradata/, the hierarchy is defined as
    # "labs/%{::labsproject}/host/%{::hostname}" and
    # "labs/%{::labsproject}/common".  We map the former
    # verbatim to "Hiera:$labsproject/host/$hostname", while the
    # latter gets simplified to "Hiera:$labsproject".  In both
    # cases, we capitalize $labsproject.
    source = source['labs/'.length..-1].chomp('/common').capitalize

    data = @cache.read(source, Hash, {}) do |content|
      YAML.load(content)
    end

    next if data.nil? || data.empty?
    next unless data.include?(key)

    new_answer = Backend.parse_answer(data[key], scope)
    case resolution_type
    when :array
      raise Exception, "Hiera type mismatch: expected Array and got #{new_answer.class}" unless new_answer.kind_of?(Array) || new_answer.kind_of?(String)
      answer ||= []
      answer << new_answer
    when :hash
      raise Exception, "Hiera type mismatch: expected Hash and got #{new_answer.class}" unless new_answer.kind_of? Hash
      answer ||= {}
      answer = Backend.merge_answer(new_answer, answer)
    else
      answer = new_answer
      break
    end
  end

  answer
end