Parameters
Pass two parameters. The first is a signed, serialized transaction. The second contains a non-emptyvalidity array.
The validity array must include a block_number predicate with an upper bound (<, <=, or =). The last block it allows must be no earlier than the block being built and within 60 seconds of submission. See Expiry.
The block number in this example is a placeholder. Before you submit, call eth_blockNumber and use the latest block number plus 10, as a 0x-prefixed hexadecimal string.
Predicates
The supported operators are
<, <=, =, !=, >, and >=. Predicate values use 0x-prefixed hexadecimal strings. The mask defaults to all ones.
A flashblock_index value must be between 1 and 10, inclusive (0x1 through 0xa in hexadecimal).
Returns
string
The 32-byte hash of the submitted transaction.