Plutus Application Backend
Pre-requisites
- Install Plutus Application Backend.
- In order to be able to balance Plutus transaction we need funds on the wallet. In case of Testnet we can request tADA from the faucet.
Overview
This guide is to show how to invoke Plutus contracts with cardano-wallet.
Workflow
Once you have created a smart contract with PAB you can execute it via cardano-wallet.
There are three endpoints that need to be invoked to follow the workflow:
- POST /wallets/{walletId}/transactions-balance - for balancing transaction from PAB.
- POST /wallets/{walletId}/transactions-sign - for signing transaction.
- POST /wallets/{walletId}/transactions-submit - for submitting transaction to the network.
Balance transaction
Plutus Application Backend provides a payload of an unbalanced transaction. This transaction needs to be balanced with wallet's inputs such that it can be submitted to the network. The response from this endpoint returns fee
and coin_selection
of the balanced transaction as well as CBOR-encoded transaction
represented in base64 encoding. We will need the returned transaction
value to pass on to POST /wallets/{walletId}/transactions-sign endpoint.
> curl -X POST http://localhost:8090/v2/wallets/1b0aa24994b4181e79116c131510f2abf6cdaa4f/transactions-balance \
-d '{"transaction":"84a500800d80018183581d704d72cf569a339a18a7d9302313983f56e0d96cd45bdcb1d6512dca6a1a001e84805820923918e403bf43c34b4ef6b48eb2ee04babed17320d8d1b9ff9ad086e86f44ec02000e80a10481d87980f5f6","redeemers":[],"inputs":[]}' \
-H "Content-Type: application/json" | jq .transaction
hKYAgYJYIJs6ATvbNwo5xpOkjHfUzr9Cv4zuFLFicFwWwpPC4ltBAw2AAYKDWB1wTXLPVpozmhin2TAjE5g/VuDZbNRb3LHWUS3KahoAHoSAWCCSORjkA79Dw0tO9rSOsu4Eur7RcyDY0bn/mtCG6G9E7IJYOQDsKgV69YfvMZdbfIT11OqtWL9bv7n++Jx0f+TDFwodcRLCv14tOV5BoBhV6ODYaS1MNdWnvKCjgBq2bfNOAhoAApgxDoALWCAvUOolRvjOAgykW/zyq+sC/xivIoNGb4iK5IkYSz0tOaEEgdh5gPX2
Sign transaction
Once the transaction is balanced we need to sign it using our wallet's secure passphrase and pass the previously returned CBOR-encoded transaction
. The sign endpoint will again return CBOR-encoded transaction
which is needed to be passed further to POST
/wallets/{walletId}/transactions-submit endpoint.
> curl -X POST http://localhost:8090/v2/wallets/1b0aa24994b4181e79116c131510f2abf6cdaa4f/transactions-sign \
-d '{"passphrase":"Secure Passphrase",
"transaction":"hKYAgYJYIJs6ATvbNwo5xpOkjHfUzr9Cv4zuFLFicFwWwpPC4ltBAw2AAYKDWB1wTXLPVpozmhin2TAjE5g/VuDZbNRb3LHWUS3KahoAHoSAWCCSORjkA79Dw0tO9rSOsu4Eur7RcyDY0bn/mtCG6G9E7IJYOQDsKgV69YfvMZdbfIT11OqtWL9bv7n++Jx0f+TDFwodcRLCv14tOV5BoBhV6ODYaS1MNdWnvKCjgBq2bfNOAhoAApgxDoALWCAvUOolRvjOAgykW/zyq+sC/xivIoNGb4iK5IkYSz0tOaEEgdh5gPX2"}' \
-H "Content-Type: application/json" | jq .transaction
hKYAgYJYIJs6ATvbNwo5xpOkjHfUzr9Cv4zuFLFicFwWwpPC4ltBAw2AAYKDWB1wTXLPVpozmhin2TAjE5g/VuDZbNRb3LHWUS3KahoAHoSAWCCSORjkA79Dw0tO9rSOsu4Eur7RcyDY0bn/mtCG6G9E7IJYOQDsKgV69YfvMZdbfIT11OqtWL9bv7n++Jx0f+TDFwodcRLCv14tOV5BoBhV6ODYaS1MNdWnvKCjgBq2bfNOAhoAApgxDoALWCAvUOolRvjOAgykW/zyq+sC/xivIoNGb4iK5IkYSz0tOaIAgYJYIAVUtVUzi4FodRYiBmO9mD5hQGo2YjjYDoCgw5gn+/w9WEAyVhMWNiK88QKW6HBXIVxQyu0E+9epkIQbCQwNjKur5ORLojHxIZtZDDfkT6caz0yxp92t4Y7rDwsDw4geMOkJBIHYeYD19g==
Submit transaction
We have our balanced and signed CBOR-encoded transaction
represented in base64 encoding. Now we can submit it to the network with POST
/wallets/{walletId}/transactions-submit endpoint.
> curl -X POST http://localhost:8090/v2/wallets/1b0aa24994b4181e79116c131510f2abf6cdaa4f/transactions-submit \
-d '{"transaction":"hKYAgYJYIJs6ATvbNwo5xpOkjHfUzr9Cv4zuFLFicFwWwpPC4ltBAw2AAYKDWB1wTXLPVpozmhin2TAjE5g/VuDZbNRb3LHWUS3KahoAHoSAWCCSORjkA79Dw0tO9rSOsu4Eur7RcyDY0bn/mtCG6G9E7IJYOQDsKgV69YfvMZdbfIT11OqtWL9bv7n++Jx0f+TDFwodcRLCv14tOV5BoBhV6ODYaS1MNdWnvKCjgBq2bfNOAhoAApgxDoALWCAvUOolRvjOAgykW/zyq+sC/xivIoNGb4iK5IkYSz0tOaIAgYJYIAVUtVUzi4FodRYiBmO9mD5hQGo2YjjYDoCgw5gn+/w9WEAyVhMWNiK88QKW6HBXIVxQyu0E+9epkIQbCQwNjKur5ORLojHxIZtZDDfkT6caz0yxp92t4Y7rDwsDw4geMOkJBIHYeYD19g=="}' \
-H "Content-Type: application/json"
{"id":"c287cd5a752ff632e07747109193ed8f8b8e446211563951e7f8e470ed859782"}
We can monitor status of the submitted transaction using GET /wallets/{walletId}/transactions/{transactionId} endpoint.
> curl -X GET http://localhost:8090/v2/wallets/1b0aa24994b4181e79116c131510f2abf6cdaa4f/transactions/c287cd5a752ff632e07747109193ed8f8b8e446211563951e7f8e470ed859782 | jq
{
"status": "in_ledger",
...
"amount": {
"quantity": 2170033,
"unit": "lovelace"
},
"inserted_at": {
"height": {
"quantity": 3324947,
"unit": "block"
},
"epoch_number": 187,
"time": "2022-02-16T11:22:12Z",
"absolute_slot_number": 50641316,
"slot_number": 226916
},
...