1
2
3
4
5
6
7
8
9
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
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
# frozen_string_literal: true
class Feature
class Definition
include ::Feature::Shared
attr_reader :path
attr_reader :attributes
PARAMS.each do |param|
define_method(param) do
attributes[param]
end
end
def initialize(path, opts = {})
@path = path
@attributes = {}
# assign nil, for all unknown opts
PARAMS.each do |param|
@attributes[param] = opts[param]
end
end
def key
name.to_sym
end
def validate!
unless name.present?
raise Feature::InvalidFeatureFlagError, "Feature flag is missing name"
end
unless path.present?
raise Feature::InvalidFeatureFlagError, "Feature flag '#{name}' is missing path"
end
unless type.present?
raise Feature::InvalidFeatureFlagError, "Feature flag '#{name}' is missing type. Ensure to update #{path}"
end
unless Definition::TYPES.include?(type.to_sym)
raise Feature::InvalidFeatureFlagError, "Feature flag '#{name}' type '#{type}' is invalid. Ensure to update #{path}"
end
unless File.basename(path, ".yml") == name
raise Feature::InvalidFeatureFlagError, "Feature flag '#{name}' has an invalid path: '#{path}'. Ensure to update #{path}"
end
unless File.basename(File.dirname(path)) == type
raise Feature::InvalidFeatureFlagError, "Feature flag '#{name}' has an invalid type: '#{path}'. Ensure to update #{path}"
end
if default_enabled.nil?
raise Feature::InvalidFeatureFlagError, "Feature flag '#{name}' is missing default_enabled. Ensure to update #{path}"
end
end
def valid_usage!(type_in_code:, default_enabled_in_code:)
unless Array(type).include?(type_in_code.to_s)
# Raise exception in test and dev
raise Feature::InvalidFeatureFlagError, "The `type:` of `#{key}` is not equal to config: " \
"#{type_in_code} vs #{type}. Ensure to use valid type in #{path} or ensure that you use " \
"a valid syntax: #{TYPES.dig(type, :example)}"
end
# We accept an array of defaults as some features are undefined
# and have `default_enabled: true/false`
unless Array(default_enabled).include?(default_enabled_in_code)
# Raise exception in test and dev
raise Feature::InvalidFeatureFlagError, "The `default_enabled:` of `#{key}` is not equal to config: " \
"#{default_enabled_in_code} vs #{default_enabled}. Ensure to update #{path}"
end
end
def to_h
attributes
end
class << self
def paths
@paths ||= [Rails.root.join('config', 'feature_flags', '**', '*.yml')]
end
def definitions
# We lazily load all definitions
# The hot reloading might request a feature flag
# before we can properly call `load_all!`
@definitions ||= load_all!
end
def reload!
@definitions = load_all!
end
def valid_usage!(key, type:, default_enabled:)
if definition = definitions[key.to_sym]
definition.valid_usage!(type_in_code: type, default_enabled_in_code: default_enabled)
elsif type_definition = self::TYPES[type]
raise InvalidFeatureFlagError, "Missing feature definition for `#{key}`" unless type_definition[:optional]
else
raise InvalidFeatureFlagError, "Unknown feature flag type used: `#{type}`"
end
end
def register_hot_reloader!
# Reload feature flags on change of this file or any `.yml`
file_watcher = Rails.configuration.file_watcher.new(reload_files, reload_directories) do
Feature::Definition.reload!
end
Rails.application.reloaders << file_watcher
Rails.application.reloader.to_run { file_watcher.execute_if_updated }
file_watcher
end
private
def load_all!
# We currently do not load feature flag definitions
# in production environments
return [] unless Gitlab.dev_or_test_env?
paths.each_with_object({}) do |glob_path, definitions|
load_all_from_path!(definitions, glob_path)
end
end
def load_from_file(path)
definition = File.read(path)
definition = YAML.safe_load(definition)
definition.deep_symbolize_keys!
self.new(path, definition).tap(&:validate!)
rescue => e
raise Feature::InvalidFeatureFlagError, "Invalid definition for `#{path}`: #{e.message}"
end
def load_all_from_path!(definitions, glob_path)
Dir.glob(glob_path).each do |path|
definition = load_from_file(path)
if previous = definitions[definition.key]
raise InvalidFeatureFlagError, "Feature flag '#{definition.key}' is already defined in '#{previous.path}'"
end
definitions[definition.key] = definition
end
end
def reload_files
[]
end
def reload_directories
paths.each_with_object({}) do |path, result|
path = File.dirname(path)
Dir.glob(path).each do |matching_dir|
result[matching_dir] = 'yml'
end
end
end
end
end
end
Feature::Definition.prepend_if_ee('EE::Feature::Definition')
|