class beem.transactionbuilder.TransactionBuilder(tx={}, blockchain_instance=None, **kwargs)

Bases: dict

This class simplifies the creation of transactions by adding operations and signers. To build your own transactions and sign them

  • tx (dict) – transaction (Optional). If not set, the new transaction is created.
  • expiration (int) – Delay in seconds until transactions are supposed to expire (optional) (default is 30)
  • blockchain_instance (Hive/Steem) – If not set, shared_blockchain_instance() is used
from beem.transactionbuilder import TransactionBuilder
from beembase.operations import Transfer
from beem import Hive
wif = "5KQwrPbwdL6PhXujxW37FSSQZ1JiwsST4cqQzDeyXtP79zkvFD3"
hive = Hive(nobroadcast=True, keys={'active': wif})
tx = TransactionBuilder(blockchain_instance=hive)
transfer = {"from": "test", "to": "test1", "amount": "1 HIVE", "memo": ""}
tx.appendSigner("test", "active") # or tx.appendWif(wif)
signed_tx = tx.sign()
broadcast_tx = tx.broadcast()
addSigningInformation(account, permission, reconstruct_tx=False)

This is a private method that adds side information to a unsigned/partial transaction in order to simplify later signing (e.g. for multisig or coldstorage)

Not needed when “appendWif” was already or is going to be used

FIXME: Does not work with owner keys!

Parameters:reconstruct_tx (bool) – when set to False and tx is already contructed, it will not reconstructed and already added signatures remain

Store which accounts/keys are supposed to sign the transaction

This method is used for an offline-signer!

appendOps(ops, append_to=None)

Append op(s) to the transaction builder

Parameters:ops (list) – One or a list of operations
appendSigner(account, permission)

Try to obtain the wif key from the wallet by telling which account and permission is supposed to sign the transaction It is possible to add more than one signer.

  • account (str) – account to sign transaction with
  • permission (str) – type of permission, e.g. “active”, “owner” etc

Add a wif that should be used for signing of the transaction.

Parameters:wif (string) – One wif key to use for signing a transaction.
broadcast(max_block_age=-1, trx_id=True)

Broadcast a transaction to the steem network Returns the signed transaction and clears itself after broadast

Clears itself when broadcast was not successfully.

  • max_block_age (int) – parameter only used for appbase ready nodes
  • trx_id (bool) – When True, trx_id is return

Clear the transaction builder and start from scratch


Clear all stored wifs

constructTx(ref_block_num=None, ref_block_prefix=None)

Construct the actual transaction and store it in the class’s dict store


Auxiliary method to obtain ref_block_num and ref_block_prefix. Requires a connection to a node!


TransactionBuilders don’t have parents, they are their own parent


Returns public key from signature


Returns public key from signature


Returns a hex value of the transaction


Check if ops is empty


Show the transaction as plain json


List all ops

searchPath(account, perm)

Set expiration date


Sign a provided transaction with the provided key(s) One or many wif keys to use for signing a transaction. The wif keys can be provided by “appendWif” or the signer can be defined “appendSigner”. The wif keys from all signer that are defined by “appendSigner will be loaded from the wallet.

Parameters:reconstruct_tx (bool) – when set to False and tx is already contructed, it will not reconstructed and already added signatures remain

Verify the authority of the signed transaction