Class: GraphQL::Subscriptions::AnyCableSubscriptions

Inherits:
GraphQL::Subscriptions show all
Defined in:
lib/graphql/subscriptions/anycable_subscriptions.rb

Constant Summary collapse

SUBSCRIPTION_PREFIX = 
"graphql-subscription:"
EVENT_PREFIX = 
"graphql-event:"
CHANNEL_PREFIX = 
"graphql-channel:"

Instance Method Summary collapse

Constructor Details

#initialize(serializer: Serialize, **rest) ⇒ AnyCableSubscriptions

Returns a new instance of AnyCableSubscriptions.

Parameters:

  • serializer (<#dump(obj), #load(string)] Used for serializing messages before handing them to `.broadcast(msg)`) (defaults to: Serialize) —

    erializer [<#dump(obj), #load(string)] Used for serializing messages before handing them to ‘.broadcast(msg)`



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# File 'lib/graphql/subscriptions/anycable_subscriptions.rb', line 60

def initialize(serializer: Serialize, **rest)
  @serializer = serializer
  super
end

Instance Method Details

#delete_channel_subscriptions(channel_id) ⇒ Object 



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# File 'lib/graphql/subscriptions/anycable_subscriptions.rb', line 127

def delete_channel_subscriptions(channel_id)
  redis.smembers(CHANNEL_PREFIX + channel_id).each do |subscription_id|
    delete_subscription(subscription_id)
  end
  redis.del(CHANNEL_PREFIX + channel_id)
end

#delete_subscription(subscription_id) ⇒ Object

The channel was closed, forget about it.



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# File 'lib/graphql/subscriptions/anycable_subscriptions.rb', line 117

def delete_subscription(subscription_id)
  # Remove subscription ids from all events
  events_data = redis.hget(SUBSCRIPTION_PREFIX + subscription_id, :events)
  events_data && JSON.parse(events_data).each do |event_topic|
    redis.srem(EVENT_PREFIX + event_topic, subscription_id)
  end
  # Delete subscription itself
  redis.del(SUBSCRIPTION_PREFIX + subscription_id)
end

#deliver(subscription_id, result) ⇒ Object

This subscription was re-evaluated. Send it to the specific stream where this client was waiting.



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# File 'lib/graphql/subscriptions/anycable_subscriptions.rb', line 75

def deliver(subscription_id, result)
  payload = { result: result.to_h, more: true }
  anycable.broadcast(SUBSCRIPTION_PREFIX + subscription_id, payload.to_json)
end

#execute_all(event, object) ⇒ Object

An event was triggered. Re-evaluate all subscribed queries and push the data over ActionCable.



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# File 'lib/graphql/subscriptions/anycable_subscriptions.rb', line 67

def execute_all(event, object)
  redis.smembers(EVENT_PREFIX + event.topic).each do |subscription_id|
    execute(subscription_id, event, object)
  end
end

#read_subscription(subscription_id) ⇒ Object

Return the query from “storage” (in redis)



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# File 'lib/graphql/subscriptions/anycable_subscriptions.rb', line 106

def read_subscription(subscription_id)
  redis.mapped_hmget(
    "#{SUBSCRIPTION_PREFIX}#{subscription_id}",
    :query_string, :variables, :context, :operation_name,
  ).tap do |subscription|
    subscription[:context]   = @serializer.load(subscription[:context])
    subscription[:variables] = JSON.parse(subscription[:variables])
  end
end

#write_subscription(query, events) ⇒ Object

Save query to “storage” (in redis)



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# File 'lib/graphql/subscriptions/anycable_subscriptions.rb', line 81

def write_subscription(query, events)
  context = query.context.to_h
  subscription_id = context[:subscription_id] ||= build_id
  channel = context.delete(:channel)
  stream = context[:action_cable_stream] ||= SUBSCRIPTION_PREFIX + subscription_id
  channel.stream_from(stream)

  data = {
    query_string: query.query_string,
    variables: query.provided_variables.to_json,
    context: @serializer.dump(context.to_h),
    operation_name: query.operation_name,
    events: events.map(&:topic).to_json,
  }

  redis.multi do
    redis.sadd(CHANNEL_PREFIX + channel.params["channelId"], subscription_id)
    redis.mapped_hmset(SUBSCRIPTION_PREFIX + subscription_id, data)
    events.each do |event|
      redis.sadd(EVENT_PREFIX + event.topic, subscription_id)
    end
  end
end