PubSubMessage Class - Flutter

Properties

id

• type: String

• Unique id of the pubsub message.

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message

• type: String

• Message that has been published on the specific topic.

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topic

• type: String

• Name of the topic.

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senderId

• type: String

• This is the id of the participant, who has sent this pubsub message.

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senderName

• type: String

• This is the name of the participant, who has sent this pubsub message.

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timestamp

• type: String

• When the message was published, as the server sends it.

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payload

• type: Map<String,dynamic>?

• This is the data that was sent with the message as the payload of publish(). It is null or empty when the sender passed none.

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PubSubMessageListener

Pass a PubSubMessageListener to subscribe(), and the same object to unsubscribe(). Every callback is optional.

onMessageReceived

• type: void Function(PubSubMessage message)?

• Called for each live message.

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onOldMessagesReceived

• type: void Function(List<PubSubMessage> messages, PubSubHistoryInfo info)?

• Called with the topic's stored messages after you subscribe. info.isLast is true on the last delivery.

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onBatchReceived

• type: void Function(List<PubSubMessage> messages)?

• Called with live messages that are delivered together.

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onMessageDrop

• type: void Function(PubSubMessageDropInfo info)?

• Called when live messages are dropped under RealtimeOverflow.DROP. info.droppedCount says how many.

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PubSubSubscribeOptions

Options for subscribe(). A field you leave out takes the server's default.

oldMessageLimit

• type: int?

• How many stored messages to deliver on subscribe. 0 skips them.

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realtimeOverflow

• type: RealtimeOverflow?

• What to do with live messages that arrive faster than the app takes them: RealtimeOverflow.QUEUE keeps them, up to maxQueue, and RealtimeOverflow.DROP drops them and reports the count to onMessageDrop.

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maxQueue

• type: int?

• The queue size for RealtimeOverflow.QUEUE. It is not allowed with RealtimeOverflow.DROP.

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newMessageLimit

• type: int?

• The most live messages delivered in one batch.

Example

final listener = PubSubMessageListener(
  onBatchReceived: (List<PubSubMessage> messages) {
    // live messages, delivered together
  },
  onMessageDrop: (PubSubMessageDropInfo info) {
    print("Dropped ${info.droppedCount} messages");
  },
);

await room.pubSub.subscribe(
  "REACTIONS",
  listener,
  const PubSubSubscribeOptions(
    oldMessageLimit: 0,
    realtimeOverflow: RealtimeOverflow.DROP,
    newMessageLimit: 20,
  ),
);