Wallet Operations Structures
The RawTxInfo object includes the following items:
| Parameter | Type | Description |
|---|---|---|
| tx_hex | string | UTXO only. The raw unsigned hex of a proposed transaction. |
| prev_txns | list | UTXO only. A list of standard InputTxns objects. |
| to | string | ETH/EVM only. A destination address to send the funds to. |
| value | string | ETH/EVM only. The amount of funds to be sent as a string with a 0x prefix, in wei units. |
| gas_limit | string | ETH/EVM only. The maximum gas to be used for sending the transaction, in gwei units. |
| pay_for_gas | object | Optional, ETH/EVM only. Used for EIP-1559 fee policy config. A standard PayForGas object. |
The InputTxns object includes the following items:
| Parameter | Type | Description |
|---|---|---|
| tx_hash | string | The transaction id of an unspent transaction from the same wallet output. |
| index | integer | The output index of this unspent transaction output. |
| script_pub_key | string | The scriptpubkey of this unspent transaction output. |
| amount | float | The value of this unspent transaction output. |
| amount |
The PayForGas object includes the following items:
| Parameter | Type | Description |
|---|---|---|
| tx_type | string | ETH/EVM coins and tokens only. Options are Legacy or Eip1559. The type of transaction values being configured. |
| gas_price | decimal | Only used if tx_type is Legacy. Values are in Gwei. The maximium price per gas unit the user is willing to pay for the transaction. |
| max_fee_per_gas | decimal | Only used if tx_type is Eip1559. Values are in Gwei. The maximum amount to pay per unit of gas to get your transaction included in a block. |
| max_priority_fee_per_gas | decimal | Only used if tx_type is Eip1559. Values are in Gwei. This is paid directly to the miner, and can be set by the user to attract minimal delay in transaction confirmation. |
| min_wait_time | integer | Optional, only used if tx_type is Eip1559. Estimated minimum transaction wait time in mempool (in ms) for this priority level. |
| max_wait_time | integer | Optional, only used if tx_type is Eip1559. Estimated maximum transaction wait time in mempool (in ms) for this priority level. |
Eip1559 allows users to save on gas fees. To use this feature for a coin/token, its entry in your coins file must include fields for chain_id and max_eth_tx_type. To allow eip-1559 transactions, max_eth_tx_type should be set to 2. To find the chain_id for an [EVM network(https://blog.thirdweb.com/evm-compatible-blockchains-and-ethereum-virtual-machine/)], refer to chainlist.org. There is also a new gas_fee_estimator parameter in the coins file, which can be set to Provider or Simple.
By default, Simple gas fee estimation suggests a fee based on fee history. If set gas_fee_estimator is set to Provider, users must set the gas_api setting in their MM2.json file to source recommended fee values from third party providers Infura or Blocknative.
To set or view the current swap transaction fee policy, use the get_swap_transaction_fee_policy and set_swap_transaction_fee_policy methods.
For more information about EIP1559, refer to https://www.blocknative.com/blog/eip-1559-fees