Class: Magick::Adapters::Registry

Inherits:
Object
  • Object
show all
Defined in:
lib/magick/adapters/registry.rb

Constant Summary collapse

CACHE_INVALIDATION_CHANNEL =
'magick:cache:invalidate'
LOCAL_WRITE_TTL =

seconds to ignore self-invalidation after a local write

2.0
FEATURE_NAME_PATTERN =

Accept only conservative feature identifiers coming off the wire. Anything outside this alphabet (newlines, spaces, Unicode punctuation, 200-char garbage) is a sign of a malformed or malicious publisher and must not be fed back into Magick.features / feature.reload.

/\A[a-zA-Z0-9_\-.:]{1,120}\z/.freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(memory_adapter, redis_adapter = nil, active_record_adapter: nil, circuit_breaker: nil, async: false, primary: nil) ⇒ Registry

Returns a new instance of Registry.



16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
# File 'lib/magick/adapters/registry.rb', line 16

def initialize(memory_adapter, redis_adapter = nil, active_record_adapter: nil, circuit_breaker: nil,
               async: false, primary: nil)
  @memory_adapter = memory_adapter
  @redis_adapter = redis_adapter
  @active_record_adapter = active_record_adapter
  @circuit_breaker = circuit_breaker || Magick::CircuitBreaker.new
  @async = async
  @primary = primary || :memory # :memory, :redis, or :active_record
  @subscriber_thread = nil
  @subscriber = nil
  @refresh_thread = nil
  @local_writes = {} # Track recent local writes to skip self-invalidation
  @reload_mutex = Mutex.new
  @stopping = false
  @shutdown_mutex = Mutex.new
  @owner_pid = Process.pid
  # Only start Pub/Sub subscriber if Redis is available
  # In memory-only mode, each process has isolated cache (no cross-process invalidation)
  start_cache_invalidation_subscriber if redis_adapter
end

Instance Attribute Details

#active_record_adapterObject (readonly)

Public so Versioning can apply tiered retention: hot window written to memory/Redis, unlimited archive written to ActiveRecord only.



364
365
366
# File 'lib/magick/adapters/registry.rb', line 364

def active_record_adapter
  @active_record_adapter
end

#memory_adapterObject (readonly)

Public so Versioning can apply tiered retention: hot window written to memory/Redis, unlimited archive written to ActiveRecord only.



364
365
366
# File 'lib/magick/adapters/registry.rb', line 364

def memory_adapter
  @memory_adapter
end

#redis_adapterObject (readonly)

Public so Versioning can apply tiered retention: hot window written to memory/Redis, unlimited archive written to ActiveRecord only.



364
365
366
# File 'lib/magick/adapters/registry.rb', line 364

def redis_adapter
  @redis_adapter
end

Instance Method Details

#all_featuresObject



174
175
176
177
178
179
180
181
182
# File 'lib/magick/adapters/registry.rb', line 174

def all_features
  features = []
  features += memory_adapter.all_features if memory_adapter
  features += redis_adapter.all_features if redis_adapter
  features += active_record_adapter.all_features if active_record_adapter
  # Version history is stored under a reserved pseudo-feature namespace;
  # it is bookkeeping, not a feature.
  features.uniq.reject { |f| f.to_s.start_with?(Versioning::STORE_PREFIX) }
end

#authoritative_get_all_data(feature_name) ⇒ Object

Read a feature's complete data straight from the shared, authoritative backend — ActiveRecord first (it is written synchronously on every set/set_all_data), then Redis — bypassing this process's local memory cache, and refresh memory with the result.

The Admin UI uses this so a toggle is reflected immediately on whichever process/container serves the (load-balanced) request after the write, instead of rendering this process's possibly-stale memory cache while it waits for Pub/Sub invalidation to arrive.



230
231
232
233
234
235
236
237
238
239
240
# File 'lib/magick/adapters/registry.rb', line 230

def authoritative_get_all_data(feature_name)
  data = read_from_source(feature_name)
  if data && !data.empty?
    memory_adapter&.set_all_data(feature_name, data)
    return data
  end

  # Source unavailable (Redis/AR down, or feature absent there) — fall back
  # to whatever this process already has rather than wiping a usable cache.
  memory_adapter ? memory_adapter.get_all_data(feature_name) : {}
end

#delete(feature_name) ⇒ Object



144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
# File 'lib/magick/adapters/registry.rb', line 144

def delete(feature_name)
  memory_adapter&.delete(feature_name)

  if redis_adapter
    begin
      redis_adapter.delete(feature_name)
      # Publish cache invalidation message
      publish_cache_invalidation(feature_name)
    rescue AdapterError
      # Continue even if Redis fails
    end
  end

  return unless active_record_adapter

  begin
    active_record_adapter.delete(feature_name)
  rescue AdapterError
    # Continue even if Active Record fails
  end
end

#ensure_subscriber!Object

Restart the Pub/Sub subscriber after a fork. The subscriber thread is not carried into child processes, so a worker inheriting a stale reference must re-create its own subscription. Safe to call on every request; it only does work when Process.pid changes.



41
42
43
44
45
46
47
48
49
50
51
52
53
54
# File 'lib/magick/adapters/registry.rb', line 41

def ensure_subscriber!
  return if @owner_pid == Process.pid

  @shutdown_mutex.synchronize do
    return if @owner_pid == Process.pid

    @subscriber_thread = nil
    @subscriber = nil
    @owner_pid = Process.pid
    @stopping = false
  end

  start_cache_invalidation_subscriber if redis_adapter
end

#exists?(feature_name) ⇒ Boolean

Returns:

  • (Boolean)


166
167
168
169
170
171
172
# File 'lib/magick/adapters/registry.rb', line 166

def exists?(feature_name)
  return true if memory_adapter&.exists?(feature_name)
  return true if redis_adapter&.exists?(feature_name) == true
  return true if active_record_adapter&.exists?(feature_name) == true

  false
end

#get(feature_name, key) ⇒ Object



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
# File 'lib/magick/adapters/registry.rb', line 77

def get(feature_name, key)
  # Try memory first (fastest) - no Redis calls needed thanks to Pub/Sub invalidation
  value = memory_adapter.get(feature_name, key) if memory_adapter
  return value unless value.nil?

  # Fall back to Redis if available
  if redis_adapter
    begin
      value = redis_adapter.get(feature_name, key)
      if !value.nil? && memory_adapter
        memory_adapter.set(feature_name, key, value)
        return value
      end
    rescue StandardError, AdapterError
      # Redis failed, continue to next adapter
    end
  end

  # Fall back to Active Record if available
  if active_record_adapter
    begin
      value = active_record_adapter.get(feature_name, key)
      memory_adapter.set(feature_name, key, value) if !value.nil? && memory_adapter
      return value
    rescue StandardError, AdapterError
      nil
    end
  end

  nil
end

#get_all_data(feature_name) ⇒ Object

Load all keys for a single feature in one call instead of N separate get() calls



185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
# File 'lib/magick/adapters/registry.rb', line 185

def get_all_data(feature_name)
  # Try memory first
  if memory_adapter
    data = memory_adapter.get_all_data(feature_name)
    return data unless data.nil? || data.empty?
  end

  # Fall back to Redis
  if redis_adapter
    begin
      data = redis_adapter.get_all_data(feature_name)
      if data && !data.empty?
        memory_adapter.set_all_data(feature_name, data) if memory_adapter
        return data
      end
    rescue StandardError, AdapterError
      # Redis failed, continue
    end
  end

  # Fall back to Active Record
  if active_record_adapter
    begin
      data = active_record_adapter.get_all_data(feature_name)
      if data && !data.empty?
        memory_adapter.set_all_data(feature_name, data) if memory_adapter
        return data
      end
    rescue StandardError, AdapterError
      # AR failed
    end
  end

  {}
end

#invalidate_cache(feature_name) ⇒ Object

Explicitly trigger cache invalidation for a feature This is useful for targeting updates that need immediate cache invalidation Invalidates memory cache in current process AND publishes to Redis for other processes



327
328
329
330
331
332
333
# File 'lib/magick/adapters/registry.rb', line 327

def invalidate_cache(feature_name)
  # Invalidate memory cache in current process immediately
  memory_adapter&.delete(feature_name)

  # Publish to Redis Pub/Sub to invalidate cache in other processes
  publish_cache_invalidation(feature_name)
end

#preload!Object

Bulk load ALL features into memory cache in minimal queries. Call this after configuration to warm the cache.



256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
# File 'lib/magick/adapters/registry.rb', line 256

def preload!
  all_data = {}

  # Load from ActiveRecord first (source of truth for persistence)
  if active_record_adapter
    begin
      all_data = active_record_adapter.load_all_features_data
    rescue StandardError, AdapterError
      # AR failed, try Redis
    end
  end

  # Merge/override with Redis data (more up-to-date than AR in most setups)
  if redis_adapter
    begin
      redis_data = redis_adapter.load_all_features_data
      redis_data.each do |feature_name, data|
        all_data[feature_name] ||= {}
        all_data[feature_name].merge!(data)
      end
    rescue StandardError, AdapterError
      # Redis failed, use what we have from AR
    end
  end

  # Populate memory cache in bulk
  if memory_adapter && !all_data.empty?
    all_data.each do |feature_name, data|
      memory_adapter.set_all_data(feature_name, data)
    end
  end

  all_data
end

#publish_cache_invalidation(feature_name) ⇒ Object

Publish cache invalidation message to Redis Pub/Sub (without deleting local memory cache) This is useful when you've just updated the cache and want to notify other processes but keep the local memory cache intact



350
351
352
353
354
355
356
357
358
359
360
# File 'lib/magick/adapters/registry.rb', line 350

def publish_cache_invalidation(feature_name)
  return unless redis_adapter

  begin
    redis_client = redis_adapter.client
    redis_client&.publish(CACHE_INVALIDATION_CHANNEL, feature_name.to_s)
  rescue StandardError => e
    # Silently fail - cache invalidation is best effort
    warn "Failed to publish cache invalidation: #{e.message}" if defined?(Rails) && Rails.env.development?
  end
end

#redis_available?Boolean

Check if Redis adapter is available

Returns:

  • (Boolean)


336
337
338
# File 'lib/magick/adapters/registry.rb', line 336

def redis_available?
  !redis_adapter.nil?
end

#redis_clientObject

Get Redis client (public method for use by other classes)



341
342
343
344
345
# File 'lib/magick/adapters/registry.rb', line 341

def redis_client
  return nil unless redis_adapter

  redis_adapter.client
end

#refresh_all_from_sourceObject

Bulk variant of #authoritative_get_all_data: refresh the local memory cache for EVERY feature from the shared backend in 1-2 queries. Returns the loaded data. Used by the Admin UI index so the full list reflects authoritative state regardless of which container serves it.



246
247
248
249
250
251
252
# File 'lib/magick/adapters/registry.rb', line 246

def refresh_all_from_source
  data = load_all_from_source
  if memory_adapter && !data.empty?
    data.each { |feature_name, feature_data| memory_adapter.set_all_data(feature_name, feature_data) }
  end
  data
end

#set(feature_name, key, value) ⇒ Object



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
# File 'lib/magick/adapters/registry.rb', line 109

def set(feature_name, key, value)
  # Update memory first (always synchronous)
  memory_adapter&.set(feature_name, key, value)

  # Record local write so the subscriber skips self-invalidation
  record_local_write(feature_name)

  # Update Redis if available
  if redis_adapter
    update_redis = proc do
      circuit_breaker.call do
        redis_adapter.set(feature_name, key, value)
      end
    rescue AdapterError => e
      warn "Failed to update Redis: #{e.message}" if defined?(Rails) && Rails.env.development?
    end

    if @async && defined?(Thread)
      spawn_async_write(feature_name, update_redis)
    else
      update_redis.call
      publish_cache_invalidation(feature_name)
    end
  end

  # Always update Active Record if available (as fallback/persistence layer)
  return unless active_record_adapter

  begin
    active_record_adapter.set(feature_name, key, value)
  rescue AdapterError => e
    warn "Failed to update Active Record: #{e.message}" if defined?(Rails) && Rails.env.development?
  end
end

#set_all_data(feature_name, data_hash) ⇒ Object

Bulk set multiple keys for a feature in one call (1 query instead of N)



292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
# File 'lib/magick/adapters/registry.rb', line 292

def set_all_data(feature_name, data_hash)
  memory_adapter&.set_all_data(feature_name, data_hash)

  # Record local write so the subscriber skips self-invalidation
  record_local_write(feature_name)

  if redis_adapter
    update_redis = proc do
      circuit_breaker.call do
        redis_adapter.set_all_data(feature_name, data_hash)
      end
    rescue AdapterError => e
      warn "Failed to bulk update Redis: #{e.message}" if defined?(Rails) && Rails.env.development?
    end

    if @async && defined?(Thread)
      spawn_async_write(feature_name, update_redis)
    else
      update_redis.call
      publish_cache_invalidation(feature_name)
    end
  end

  if active_record_adapter
    begin
      active_record_adapter.set_all_data(feature_name, data_hash)
    rescue AdapterError => e
      warn "Failed to bulk update Active Record: #{e.message}" if defined?(Rails) && Rails.env.development?
    end
  end
end

#shutdown(timeout: 5) ⇒ Object

Gracefully terminate the Pub/Sub subscriber thread and its Redis connection. Without this, Ruby/Puma shutdown waits on the blocking subscribe call.



58
59
60
61
62
63
64
65
66
67
68
69
70
71
# File 'lib/magick/adapters/registry.rb', line 58

def shutdown(timeout: 5)
  @shutdown_mutex.synchronize do
    return if @stopping

    @stopping = true
  end

  close_subscriber_connection(@subscriber)
  terminate_subscriber_thread(@subscriber_thread, timeout)

  @subscriber = nil
  @subscriber_thread = nil
  true
end

#stopping?Boolean

Returns:

  • (Boolean)


73
74
75
# File 'lib/magick/adapters/registry.rb', line 73

def stopping?
  @stopping == true
end