subscribe method

Future<ResultOfSubscribeCollection> subscribe(
  1. ParamsOfSubscribe params
)

The subscription is a persistent communication channel between client and Everscale Network.

Important Notes on Subscriptions

Unfortunately sometimes the connection with the network breaks down. In this situation the library attempts to reconnect to the network. This reconnection sequence can take significant time. All of this time the client is disconnected from the network.

Bad news is that all changes that happened while the client was disconnected are lost.

Good news is that the client report errors to the callback when it loses and resumes connection.

So, if the lost changes are important to the application then the application must handle these error reports.

Library reports errors with responseType == 101 and the error object passed via params.

When the library has successfully reconnected the application receives callback with responseType == 101 and params.code == 614 (NetworkModuleResumed).

Application can use several ways to handle this situation:

  • If application monitors changes for the single object (for example specific account): application can perform a query for this object and handle actual data as a regular data from the subscription.
  • If application monitors sequence of some objects (for example transactions of the specific account): application must refresh all cached (or visible to user) lists where this sequences presents.

Implementation

Future<ResultOfSubscribeCollection> subscribe(
    ParamsOfSubscribe params) async {
  final res = await _tonCore.request(
      'net.subscribe', params.toString());
  return ResultOfSubscribeCollection.fromMap(res);
}