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
|
# frozen_string_literal: true
# The usage of the ReactiveCaching module is documented here:
# https://docs.gitlab.com/ee/development/utilities.html#reactivecaching
module ReactiveCaching
extend ActiveSupport::Concern
InvalidateReactiveCache = Class.new(StandardError)
ExceededReactiveCacheLimit = Class.new(StandardError)
included do
class_attribute :reactive_cache_key
class_attribute :reactive_cache_lease_timeout
class_attribute :reactive_cache_refresh_interval
class_attribute :reactive_cache_lifetime
class_attribute :reactive_cache_hard_limit
class_attribute :reactive_cache_worker_finder
# defaults
self.reactive_cache_key = -> (record) { [model_name.singular, record.id] }
self.reactive_cache_lease_timeout = 2.minutes
self.reactive_cache_refresh_interval = 1.minute
self.reactive_cache_lifetime = 10.minutes
self.reactive_cache_hard_limit = 1.megabyte
self.reactive_cache_worker_finder = ->(id, *_args) do
find_by(primary_key => id)
end
def calculate_reactive_cache(*args)
raise NotImplementedError
end
def reactive_cache_updated(*args)
end
def with_reactive_cache(*args, &blk)
unless within_reactive_cache_lifetime?(*args)
refresh_reactive_cache!(*args)
return
end
keep_alive_reactive_cache!(*args)
begin
data = Rails.cache.read(full_reactive_cache_key(*args))
yield data unless data.nil?
rescue InvalidateReactiveCache
refresh_reactive_cache!(*args)
nil
end
end
# This method is used for debugging purposes and should not be used otherwise.
def without_reactive_cache(*args, &blk)
return with_reactive_cache(*args, &blk) unless Rails.env.development?
data = self.class.reactive_cache_worker_finder.call(id, *args).calculate_reactive_cache(*args)
yield data
end
def clear_reactive_cache!(*args)
Rails.cache.delete(full_reactive_cache_key(*args))
Rails.cache.delete(alive_reactive_cache_key(*args))
end
def exclusively_update_reactive_cache!(*args)
locking_reactive_cache(*args) do
key = full_reactive_cache_key(*args)
if within_reactive_cache_lifetime?(*args)
enqueuing_update(*args) do
new_value = calculate_reactive_cache(*args)
check_exceeded_reactive_cache_limit!(new_value)
old_value = Rails.cache.read(key)
Rails.cache.write(key, new_value)
reactive_cache_updated(*args) if new_value != old_value
end
else
Rails.cache.delete(key)
end
end
end
private
def refresh_reactive_cache!(*args)
clear_reactive_cache!(*args)
keep_alive_reactive_cache!(*args)
ReactiveCachingWorker.perform_async(self.class, id, *args)
end
def keep_alive_reactive_cache!(*args)
Rails.cache.write(alive_reactive_cache_key(*args), true, expires_in: self.class.reactive_cache_lifetime)
end
def full_reactive_cache_key(*qualifiers)
prefix = self.class.reactive_cache_key
prefix = prefix.call(self) if prefix.respond_to?(:call)
([prefix].flatten + qualifiers).join(':')
end
def alive_reactive_cache_key(*qualifiers)
full_reactive_cache_key(*(qualifiers + ['alive']))
end
def locking_reactive_cache(*args)
lease = Gitlab::ExclusiveLease.new(full_reactive_cache_key(*args), timeout: reactive_cache_lease_timeout)
uuid = lease.try_obtain
yield if uuid
ensure
Gitlab::ExclusiveLease.cancel(full_reactive_cache_key(*args), uuid)
end
def within_reactive_cache_lifetime?(*args)
Rails.cache.exist?(alive_reactive_cache_key(*args))
end
def enqueuing_update(*args)
yield
ReactiveCachingWorker.perform_in(self.class.reactive_cache_refresh_interval, self.class, id, *args)
end
def check_exceeded_reactive_cache_limit!(data)
return unless Feature.enabled?(:reactive_cache_limit)
data_deep_size = Gitlab::Utils::DeepSize.new(data, max_size: self.class.reactive_cache_hard_limit)
raise ExceededReactiveCacheLimit.new unless data_deep_size.valid?
end
end
end
|