Create a simple transaction
You will need a new payment address (payment2.addr) so that you can send funds to it. First, get a new payment key pair for that:
cardano-cli address key-gen \--verification-key-file payment2.vkey \--signing-key-file payment2.skey
This has created two new keys: payment2.vkey and payment2.skey
To generate payment2.addr we can use the same stake key pair that we already have:
cardano-cli address build \--payment-verification-key-file payment2.vkey \--out-file payment2.addr \--testnet-magic 1097911063
Let's send 100 ada (100,000,000 lovelace) from payment.addr to payment2.addr
Creating a transaction is a process that requires various steps:
Get the protocol parameters
Define the time-to-live (TTL) for the transaction
Calculate the fee
Build the transaction
Sign the transaction
Submit the transaction
Get the protocol parameters and save them to protocol.json with:
cardano-cli query protocol-parameters \--allegra-era \--testnet-magic 1097911063 \--out-file protocol.json
We need the CURRENT TIP of the blockchain, this is, the height of the last block produced. We are looking for the value of SlotNo
cardano-cli query tip --testnet-magic 1097911063​{"blockNo": 16829,"headerHash": "3e6f59b10d605e7f59ba8383cb0ddcd42480ddcc0a85d41bad1e4648eb5465ad","slotNo": 369215}
So at this moment the tip is on block: 369215 .
To build the transaction we need to specify the TTL (Time To Live), this is the block height limit for our transaction to be included in a block, if it is not in a block by that slot the transaction will be cancelled.
From protocol.json we know that we have 1 slot per second. Lets say that it will take us 10 minutes to build the transaction, and that we want to give it another 10 minutes window to be included in a block. So we need 20 minutes or 1200 slots. So we add 1200 to the current tip: 369215 + 1200 = 370415. So our TTL is 370415
We create a draft for the transaction and save it in tx.raw
We need the transaction hash and index of the UTXO we want to spend:
cardano-cli query utxo \--allegra-era \--address $(cat payment.addr) \--testnet-magic 1097911063​> TxHash TxIx Lovelace> ----------------------------------------------------------------------------------------> 4e3a6e7fdcb0d0efa17bf79c13aed2b4cb9baf37fb1aa2e39553d5bd720c5c99 1 1000000000
Note that for --tx-in we use the following syntax: TxId#TxIx where TxId is the transaction hash and TxIx is the index (you found these values in the above step) they will be added like this 4e3a6e7fdcb0d0efa17bf79c13aed2b4cb9baf37fb1aa2e39553d5bd720c5c99#1.
For --tx-out we use: TxOut+Lovelace where TxOut is the hex encoded address followed by the amount in Lovelace. --tx-out $(cat payment.addr)+0, --ttl, --fees, are all 0 for now. We will revisit these in a later step after we calculate fees and ttl.
cardano-cli transaction build-raw \--tx-in 4e3a6e7fdcb0d0efa17bf79c13aed2b4cb9baf37fb1aa2e39553d5bd720c5c99#1 \--tx-out $(cat payment2.addr)+100000000 \--tx-out $(cat payment.addr)+0 \--ttl 0 \--fee 0 \--out-file tx.raw
The transaction needs one (1) input: a valid UTXO from payment.addr, and two (2) outputs: The receiving address payment2.addr and an address to send the change back, in this case we use payment.addr. You also need to include the Draft transaction file. Witnesses are _**_number of signing keys used to sign the transaction.
cardano-cli transaction calculate-min-fee \--tx-body-file tx.raw \--tx-in-count 1 \--tx-out-count 2 \--witness-count 1 \--byron-witness-count 0 \--testnet-magic 1097911063 \--protocol-params-file protocol.json​​> 174433 Lovelace
(--testnet-magic 1097911063 identifies the Shelley Testnet. Other testnets will use other numbers, and mainnet uses --mainnet instead.)
So we need to pay 174433 lovelace fee to create this transaction.
Assuming we want to send 100 ada to payment2.addr spending a UTXO containing 1,000,000 ada (1,000,000,000,000 lovelace), now we need to calculate how much is the change to send back to payment.addr
expr 1000000000 - 100000000 - 174433​> 899825567
Now we revisit the tx.raw file from the "Draft the transaction" section above.
Note that all the arguments will be the same for the first three lines, but we will now add the values we discovered above for the next 3 lines.
cardano-cli transaction build-raw \--tx-in 4e3a6e7fdcb0d0efa17bf79c13aed2b4cb9baf37fb1aa2e39553d5bd720c5c99#1 \--tx-out $(cat payment2.addr)+100000000 \--tx-out $(cat payment.addr)+899825567 \--ttl 370415 \--fee 174433 \--out-file tx.raw
Sign the transaction with the signing key payment.skey and save the signed transaction in tx.signed
cardano-cli transaction sign \--tx-body-file tx.raw \--signing-key-file payment.skey \--testnet-magic 1097911063 \--out-file tx.signed
Make sure that your node is running and set CARDANO_NODE_SOCKET_PATH variable to:
export CARDANO_NODE_SOCKET_PATH=~/cardano-node/relay/db/node.socket
and submit the transaction:
cardano-cli transaction submit \--tx-file tx.signed \--testnet-magic 1097911063
We must give it some time to get incorporated into the blockchain, but eventually, we will see the effect:
cardano-cli query utxo \--allegra-era \--address $(cat payment.addr) \--testnet-magic 1097911063​> TxHash TxIx Lovelace> ----------------------------------------------------------------------------------------> b64ae44e1195b04663ab863b62337e626c65b0c9855a9fbb9ef4458f81a6f5ee 1 899825567​cardano-cli query utxo \--allegra-era \--address $(cat payment2.addr) \--testnet-magic 1097911063​> TxHash TxIx Lovelace> ----------------------------------------------------------------------------------------> b64ae44e1195b04663ab863b62337e626c65b0c9855a9fbb9ef4458f81a6f5ee 0 100000000
QUESTIONS AND FEEDBACK
If you have any questions and suggestions while taking the lessons please feel free to ask in the forum and we will respond as soon as possible.
