bitcoindevkit
User should have a way to know that a transaction changed its state
Right now if users want to know if a transaction was removed from the chain, or dropped from the mempool, they need to compare two versions of list_unspent obtained in different moments.
We should investigate if we can provide some method to do this on our end.
The use case for this is: a user just synced with the backend, wants to know which transactions disappeared.
Edit: this can be further generalized to be a way to notify users when transactions/utxos change state (confirmation, drop from mempool, reorg, but also replacement, etc)
Right now if users want to know if a transaction was removed from the chain, or dropped from the mempool, they need to compare two versions of list_unspent obtained in different moments.
| Module | Data type | Method(s) to compare state with |
|---|---|---|
bdk_chain |
UTXOs | TxGraph::filter_chain_unspents, TxGraph::try_filter_chain_unspents |
bdk_chain |
Transactions | TxGraph::list_chain_txs, TxGraph::try_list_chain_txs |
bdk_wallet |
UTXOs | Wallet::list_unspent |
bdk_wallet |
Transactions | Wallet::transactions |
Before introducing a way of notifying users of a state change we should have a way of determining the current state of a transaction more precisely. Right now we only have canonical (confirmed or unconfirmed) or not canonical. This is not enough -- I want to know why a transaction is non-canonical. This is usually a conflict was confirmed or seen more recently.
In terms of listing I think we should have a way of listing all transactions in the order they were first seen (see: https://github.com/bitcoindevkit/bdk/issues/1333) and what the current state of them is. You usually don't want to just forget about a transaction when you've broadcast it. RBF happens infrequently enough it's better to leave it in the app's transaction list and just indicate that the tx was replaced by another.
