Method: POST signrawtransaction
Sign inputs for raw transaction (serialized, hex-encoded).
The second optional argument (may be null) is an array of previous transaction outputs that this transaction depends on but may not yet be in the block chain.
The third optional argument (may be null) is an array of base58-encoded private keys that, if given, will be the only keys used to sign the transaction.
hexstring - string
The transaction hex string.
prevtxs - string
An json array of previous dependent transaction outputs.
privatekeys - string
A json array of base58-encoded private keys for signing.
sighashtype - string
The signature hash type. Must be one of
branchid - string
The hex representation of the consensus branch id to sign with. This can be used to force signing with consensus rules that are ahead of the node's current height.