Class: SolidObjects::ActorChannel

Inherits:
ActionCable::Channel::Base show all
Defined in:
lib/solid_objects/actor_channel.rb,
sig/generated/lib/solid_objects/actor_channel.rbs

Constant Summary collapse

REJECT_REASONS =

Returns:

  • (Object) 
{
  UnknownActorType => "unregistered_actor_type",
  InvalidStreamToken => "invalid_stream_token",
  InvalidComponentToken => "invalid_component_token",
  JSON::ParserError => "malformed_component_registration",
  KeyError => "missing_subscription_parameter"
}.freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#component_subscriptions ⇒ Object (readonly)

Returns the value of attribute component_subscriptions.

Returns:

  • (Object) 


62
63
64
 
# File 'lib/solid_objects/actor_channel.rb', line 62

def component_subscriptions
  @component_subscriptions
end

#payload_names ⇒ Object (readonly)

Returns the value of attribute payload_names.

Returns:

  • (Object) 


62
63
64
 
# File 'lib/solid_objects/actor_channel.rb', line 62

def payload_names
  @payload_names
end

#reference ⇒ Object (readonly)

Returns the value of attribute reference.

Returns:

  • (Object) 


62
63
64
 
# File 'lib/solid_objects/actor_channel.rb', line 62

def reference
  @reference
end

#scalar_observables ⇒ Object (readonly)

Returns the value of attribute scalar_observables.

Returns:

  • (Object) 


62
63
64
 
# File 'lib/solid_objects/actor_channel.rb', line 62

def scalar_observables
  @scalar_observables
end

Instance Method Details

#newer_payload_revision?(snapshot) ⇒ Boolean

RBS:

  • (ActorSnapshot) -> bool

Parameters:

Returns:

  • (Boolean) 


165
166
167
168
169
170
 
# File 'lib/solid_objects/actor_channel.rb', line 165

def newer_payload_revision?(snapshot)
  current = @payload_revision
  return true unless current

  (current <=> [ snapshot.instance_id, snapshot.revision ]) == -1
end

#payload_authorization_context(name) ⇒ Object

Resolves the Cable connection to whatever the application uses as an authorization subject, so a payload block and authorize_query see the same object a controller render would pass.

RBS:

  • (String) -> untyped

Parameters:

  • (String)

Returns:

  • (Object) 


157
158
159
160
161
162
 
# File 'lib/solid_objects/actor_channel.rb', line 157

def payload_authorization_context(name)
  callable = SolidObjects.configuration.payload_authorization_context
  return callable.call(connection:) unless CallableKeywords.accepts?(callable, :payload_name)

  callable.call(connection:, payload_name: name)
end

#receive_broadcast(stream) ⇒ void

This method returns an undefined value.

RBS:

  • (String) -> void

Parameters:

  • (String) 


88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
 
# File 'lib/solid_objects/actor_channel.rb', line 88

def receive_broadcast(stream)
  invalidation = TurboStreamRenderer.invalidation(stream)
  revision_only = invalidation &&
    invalidation.fetch("observable_name") == PayloadBroadcast::REVISION_OBSERVABLE
  if !revision_only &&
      (!invalidation ||
        scalar_observables.nil? ||
        scalar_observables.include?(invalidation.fetch("observable_name")))
    transmit stream
  end
  return unless invalidation

  component_subscriptions
    .refreshes_for(invalidation)
    .each { |refresh| transmit refresh }
  transmit_state_payloads(ActorSnapshot.new(reference))
end

#refresh_outdated_components(snapshot) ⇒ void

This method returns an undefined value.

RBS:

  • (ActorSnapshot) -> void

Parameters:



188
189
190
191
192
 
# File 'lib/solid_objects/actor_channel.rb', line 188

def refresh_outdated_components(snapshot)
  component_subscriptions
    .reconnect_refreshes(snapshot)
    .each { |refresh| transmit refresh }
end

#reject_and_report(reason, actor_type:, actor_id:, error: nil) ⇒ void

This method returns an undefined value.

The exception message stays out of the payload, because a component or payload error can carry actor state into logs.

RBS:

  • (String, actor_type: String?, actor_id: String?, ?error: Exception?) -> void

Parameters:

  • (String)
  • actor_type: (String, nil)
  • actor_id: (String, nil)
  • error: (Exception, nil) (defaults to: nil) 


70
71
72
73
74
75
76
77
78
79
 
# File 'lib/solid_objects/actor_channel.rb', line 70

def reject_and_report(reason, actor_type:, actor_id:, error: nil)
  SolidObjects.instrument(
    :"subscription.rejected",
    reason:,
    actor_type:,
    actor_id:,
    error_class: error&.class&.name
  )
  reject
end

#reject_reason(error) ⇒ String

RBS:

  • (Exception) -> String

Parameters:

  • (Exception)

Returns:

  • (String) 


82
83
84
85
 
# File 'lib/solid_objects/actor_channel.rb', line 82

def reject_reason(error)
  match = REJECT_REASONS.find { |error_class, _| error.is_a?(error_class) }
  match ? match.last : "invalid_subscription"
end

#scalar_observable_names(snapshot) ⇒ Array[String]

RBS:

  • (ActorSnapshot) -> Array[String]

Parameters:

Returns:

  • (Array[String]) 


212
213
214
215
216
217
218
219
 
# File 'lib/solid_objects/actor_channel.rb', line 212

def scalar_observable_names(snapshot)
  return scalar_observables if scalar_observables

  definition = snapshot.actor_class.definition
  definition.observables.keys.filter_map do |name|
    name.to_s if definition.broadcasts_observable_value?(name)
  end
end

#subscribed ⇒ void

This method returns an undefined value.

RBS:

  • () -> void



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
 
# File 'lib/solid_objects/actor_channel.rb', line 16

def subscribed
  identity = StreamToken.verify(params.fetch("token"))
  actor_type = identity.fetch("actor_type")
  actor_id = identity.fetch("actor_id")
  SolidObjects.registry.fetch(actor_type)
  authorized = SolidObjects.configuration.authorize_subscription.call(
    actor_type:,
    actor_id:,
    authorization_context: connection
  )
  unless authorized
    return reject_and_report("unauthorized", actor_type:, actor_id:)
  end

  @reference = Reference.new(actor_type:, actor_id:)
  @scalar_observables = identity["observables"]
  @payload_names = identity["payloads"]
  validate_scalar_observables!
  validate_payload_names!
  @component_subscriptions = ComponentSubscriptions.parse(
    params["components"],
    reference:
  )
  stream_from StreamName.for(reference), coder: ActiveSupport::JSON do |stream|
    receive_broadcast(stream)
  end
  snapshot = ActorSnapshot.new(reference)
  scalar_observable_names(snapshot).each do |name|
    transmit TurboStreamRenderer.observable_value(
      reference:,
      name:,
      value: snapshot.observable_value(name)
    )
  end
  refresh_outdated_components(snapshot)
  transmit_state_payloads(snapshot)
rescue KeyError,
  JSON::ParserError,
  InvalidStreamToken,
  InvalidComponentToken,
  UnknownActorType => error
  reject_and_report(reject_reason(error), actor_type:, actor_id:, error:)
end

#transmit_state_payload(snapshot, name) ⇒ Boolean

A payload is one subscriber's view of one name. Letting it raise through here would reject the subscription or abandon the rest of a broadcast, so a failure is confined to the payload that caused it and reported. The exception message is deliberately not instrumented: a payload block reads actor state, so its message is the one place subscriber state could leak into logs.

Returns whether this revision was settled for the name. An unauthorized payload is settled: the decision is stable, so retrying it would only re-deliver its authorized siblings.

RBS:

  • (ActorSnapshot, String) -> bool

Parameters:

Returns:

  • (Boolean) 


132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
 
# File 'lib/solid_objects/actor_channel.rb', line 132

def transmit_state_payload(snapshot, name)
  payload = PayloadBroadcast.new(
    snapshot:,
    name:,
    authorization_context: payload_authorization_context(name)
  ).call
  transmit TurboStreamRenderer.state_payload(payload)
  true
rescue Unauthorized
  true
rescue => error
  SolidObjects.instrument(
    :payload_broadcast_failed,
    actor_type: reference.actor_type,
    actor_id: reference.actor_id,
    payload_name: name,
    error_class: error.class.name
  )
  false
end

#transmit_state_payloads(snapshot) ⇒ void

This method returns an undefined value.

RBS:

  • (ActorSnapshot) -> void

Parameters:



107
108
109
110
111
112
113
114
115
116
117
118
119
 
# File 'lib/solid_objects/actor_channel.rb', line 107

def transmit_state_payloads(snapshot)
  return if payload_names.nil? || payload_names.empty?
  return unless newer_payload_revision?(snapshot)

  # The watermark records what the subscriber has, so a revision with a
  # failed payload must not advance it: dedup would skip every later
  # attempt at that revision and the actor may not mutate again for a long
  # time. Every name is still attempted before the decision is made.
  attempts = payload_names.map { |name| transmit_state_payload(snapshot, name) }
  return if attempts.any?(false)

  @payload_revision = [ snapshot.instance_id, snapshot.revision ]
end

#validate_payload_names! ⇒ void

This method returns an undefined value.

RBS:

  • () -> void



173
174
175
176
177
178
179
180
181
182
183
184
185
 
# File 'lib/solid_objects/actor_channel.rb', line 173

def validate_payload_names!
  return unless payload_names

  broadcasts = SolidObjects
    .registry
    .fetch(reference.actor_type)
    .definition
    .payload_broadcasts
  unknown = payload_names.find { |name| !broadcasts.key?(name.to_sym) }
  return unless unknown

  raise InvalidStreamToken, "unknown payload broadcast #{unknown.inspect}"
end

#validate_scalar_observables! ⇒ void

This method returns an undefined value.

RBS:

  • () -> void



195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
 
# File 'lib/solid_objects/actor_channel.rb', line 195

def validate_scalar_observables!
  return unless scalar_observables

  definition = SolidObjects
    .registry
    .fetch(reference.actor_type)
    .definition
  unknown = scalar_observables.find do |name|
    !definition.observables.key?(name.to_sym) ||
      !definition.broadcasts_observable_value?(name)
  end
  return unless unknown

  raise InvalidStreamToken, "unknown scalar observable #{unknown.inspect}"
end