Module: Services::Base::UniquenessChecker

Defined in:
lib/services/modules/uniqueness_checker.rb

Constant Summary collapse

KEY_PREFIX = 
%w(
  services
  uniqueness
).join(':').freeze
ON_ERROR = 
%i(
  fail
  ignore
  reschedule
  return
).freeze
MAX_RETRIES = 
10.freeze
THIRTY_DAYS = 
(60 * 60 * 24 * 30).freeze

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.prepended(mod) ⇒ Object 



19
20
21
 
# File 'lib/services/modules/uniqueness_checker.rb', line 19

def self.prepended(mod)
  mod.const_set :NotUniqueError, Class.new(mod::Error)
end

Instance Method Details

#call(*args, **kwargs) ⇒ Object 



45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
 
# File 'lib/services/modules/uniqueness_checker.rb', line 45

def call(*args, **kwargs)
  @_service_args = args
  super
rescue self.class::NotUniqueError => e
  case @_on_error.to_sym
  when :fail
    raise e
  when :reschedule
    if @_retries_exhausted
      raise e
    else
      increase_error_count
      reschedule
    end
  when :return
    return e
  else
    raise "Unexpected on_error: #{@_on_error}"
  end
ensure
  Services.redis.del @_uniqueness_keys unless Array(@_uniqueness_keys).empty?
  Services.redis.del error_count_key
end

#check_uniqueness(*args, on_error: :fail) ⇒ Object 



23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
 
# File 'lib/services/modules/uniqueness_checker.rb', line 23

def check_uniqueness(*args, on_error: :fail)
  raise "on_error must be one of #{ON_ERROR.join(', ')}, but was #{on_error}" unless ON_ERROR.include?(on_error.to_sym)
  @_on_error = on_error
  raise 'Service args not found.' if @_service_args.nil?
  @_uniqueness_args = args.empty? ? @_service_args : args
  new_uniqueness_key = uniqueness_key(@_uniqueness_args)
  raise "A uniqueness key with args #{@_uniqueness_args.inspect} already exists." if @_uniqueness_keys && @_uniqueness_keys.include?(new_uniqueness_key)
  if @_similar_service_id = Services.redis.get(new_uniqueness_key)
    if on_error.to_sym == :ignore
      return false
    else
      @_retries_exhausted = on_error.to_sym == :reschedule && error_count >= MAX_RETRIES
      raise_not_unique_error
    end
  else
    @_uniqueness_keys ||= []
    @_uniqueness_keys << new_uniqueness_key
    Services.redis.setex new_uniqueness_key, THIRTY_DAYS, @id
    true
  end
end