query_transaction_tree method

Future<ResultOfQueryTransactionTree> query_transaction_tree(
  1. ParamsOfQueryTransactionTree params
)

Performs recursive retrieval of a transactions tree produced by a specific message: in_msg -> dst_transaction -> out_messages -> dst_transaction -> ... If the chain of transactions execution is in progress while the function is running, it will wait for the next transactions to appear until the full tree or more than 50 transactions are received.

All the retrieved messages and transactions are included into result.messages and result.transactions respectively.

Function reads transactions layer by layer, by pages of 20 transactions.

The retrieval process goes like this: Let's assume we have an infinite chain of transactions and each transaction generates 5 messages.

  1. Retrieve 1st message (input parameter) and corresponding transaction - put it into result. It is the first level of the tree of transactions - its root. Retrieve 5 out message ids from the transaction for next steps.
  2. Retrieve 5 messages and corresponding transactions on the 2nd layer. Put them into result. Retrieve 5*5 out message ids from these transactions for next steps
  3. Retrieve 20 (size of the page) messages and transactions (3rd layer) and 20*5=100 message ids (4th layer).
  4. Retrieve the last 5 messages and 5 transactions on the 3rd layer + 15 messages and transactions (of 100) from the 4th layer
  • 25 message ids of the 4th layer + 75 message ids of the 5th layer.
  1. Retrieve 20 more messages and 20 more transactions of the 4th layer + 100 more message ids of the 5th layer.
  2. Now we have 1+5+20+20+20 = 66 transactions, which is more than 50. Function exits with the tree of 1m->1t->5m->5t->25m->25t->35m->35t. If we see any message ids in the last transactions out_msgs, which don't have corresponding messages in the function result, it means that the full tree was not received and we need to continue iteration.

To summarize, it is guaranteed that each message in result.messages has the corresponding transaction in the result.transactions. But there is no guarantee that all messages from transactions out_msgs are presented in result.messages. So the application has to continue retrieval for missing messages if it requires.

Implementation

Future<ResultOfQueryTransactionTree> query_transaction_tree(
    ParamsOfQueryTransactionTree params) async {
  final res = await _tonCore.request(
      'net.query_transaction_tree', params.toString());
  return ResultOfQueryTransactionTree.fromMap(res);
}