Contains code definining the Miden node's block-producer component. It is responsible for ordering transactions into blocks and submitting these for inclusion in the blockchain.
It serves a small gRPC API which the node's RPC component uses to submit new transactions. In turn,
the block-producer uses the store's gRPC API to submit blocks and query chain state.
For more information on the installation and operation of this component, please see the node's readme.
The full gRPC API can be found here.
Submits a proven transaction to the block-producer, returning the current chain height if successful.
The block-producer does not verify the transaction's proof as it assumes the RPC component has done so. This is done to minimize the performance impact of new transactions on the block-producer.
Transactions are verified before being added to the block-producer's mempool. Transaction which fail verification are rejected and an error is returned. Possible reasons for verification failure include
- current account state does not match the transaction's initial account state
- transaction attempts to consume non-existing, or already consumed notes
- transaction attempts to create a duplicate note
- invalid transaction proof (checked by the RPC component)
Verified transactions are added to the mempool however they are still not guaranteed to make it into a block. Transactions may be evicted from the mempool if their preconditions no longer hold. Currently the only precondition is transaction expiration height. Furthermore, as a defense against bugs the mempool may evict transactions it deems buggy e.g. cause block proofs to fail due to some bug in the VM, compiler, prover etc.
Since transactions can depend on other transactions in the mempool this means a specific transaction may be evicted if:
- it's own expiration height is exceeded, or
- it is deemed buggy by the mempool, or
- any ancestor transaction in the mempool is evicted
This list will be extended in the future e.g. eviction due to gas price fluctuations.
Note that since the RPC response only indicates admission into the mempool, its not directly possible to know if the transaction was evicted. The best way to ensure this is to effectively add a timeout to the transaction by setting the transaction's expiration height. Once the blockchain advances beyond this point without including the transaction you can know for certain it was evicted.
This project is MIT licensed.