ICRC Rosetta construction API reference
The construction API allows for offline signing of transactions and then posting them on ICP at a later point in time. It is recommended to first go through flow of operations of the construction API to gain an understanding of how it works, what endpoints to call with what parameters, and where the user has to take action upon receiving certain responses.
Currently, the construction API of Rosetta supports only one category of transactions, which is the transfer of assets. According to the ICRC-1 and ICRC-2 standards, this can be done in the following ways:
- Direct transfers: This is the most basic functionality. In accordance with the ICRC-1 standard, you can use Rosetta to transfer ICRC tokens.
- Approve spender: You can approve a spender to spend your tokens for you. This feature adheres to the ICRC-2 standard.
Approve a spender
This section will show you how to use the ICRC Rosetta implementation to authorize a spender to spend your ICRC-1 tokens. Make sure you are familiar with the flow of operations for Rosetta.
The request types used for making direct transfers are APPROVE and SPENDER. They consist of two operations, one for the approve operation and another for the spender operation.
You do not have to specify the FEE operation, although the FEE of the ICRC-1 ledger FEE will be deducted automatically by Rosetta.
Calls may include a FEE operation to not overlook unexpected debit operations.
Example
An example of the minimum set of operations that is sent to the construction/payloads endpoint can be found below.
In this example, you are approving the principal xmiu5-jqaaa-aaaag-qbz7q-cai to spend up to 10 e8 ckBTC from the principal.
iowfl-yzooa-br3dt-77erl-nlm7f-kplhq-php75-hw3an-aeqn2-swh4t-3qe.
curl --location '0.0.0.0:8082/construction/payloads' --header 'Content-Type: application/json' --data '{
"network_identifier": {
"blockchain": "Internet Computer",
"network": "mc6ru-gyaaa-aaaar-qaaaq-cai"
},
"public_keys": [
{
"hex_bytes": "047a83e378053f87b49aeae53b3ed274c8b2ffbe59d9a51e3c4d850ca8ac1684f7131b778317c0db04de661c7d08321d60c0507868af41fe3150d21b3c6c757367",
"curve_type": "secp256k1"
}
],
"operations": [
{
"operation_identifier": {
"index": 0
},
"type": "APPROVE",
"account": {
"address": "iowfl-yzooa-br3dt-77erl-nlm7f-kplhq-php75-hw3an-aeqn2-swh4t-3qe",
"sub_account": {
"address": "0000000000000000000000000000000000000000000000000000000000000000"
}
},
"amount": null,
"metadata": {
"allowance": {
"value": "10",
"currency": {
"symbol": "ckBTC",
"decimals": 8
}
},
"expected_allowance": null,
"expires_at": null
}
},
{
"operation_identifier": {
"index": 1
},
"type": "SPENDER",
"account": {
"address": "xmiu5-jqaaa-aaaag-qbz7q-cai",
"sub_account": {
"address": "0000000000000000000000000000000000000000000000000000000000000000"
}
}
}
],
"metadata": null
}'
Direct transfer of tokens
The request type that is used for making direct transfers is TRANSFER. In the simplest form, it consists of two operations, one for the debit operation and one for the credit operation.
You do not have to specify the FEE operation, although the FEE of the ICRC-1 ledger will be deducted automatically by Rosetta.
The call may include a FEE operation to not overlook unexpected debit operations.
Example
An example of the minimum set of operations that is sent to the construction/payloads endpoint can be found below.
In this example, you are sending 10 e8 ckBTC from principal iowfl-yzooa-br3dt-77erl-nlm7f-kplhq-php75-hw3an-aeqn2-swh4t-3qe to principal xmiu5-jqaaa-aaaag-qbz7q-cai.
curl --location '0.0.0.0:8082/construction/payloads' --header 'Content-Type: application/json' --data
'{
"network_identifier": {
"blockchain": "Internet Computer",
"network": "mxzaz-hqaaa-aaaar-qaada-cai"
},
"public_keys": [
{
"hex_bytes": "047a83e378053f87b49aeae53b3ed274c8b2ffbe59d9a51e3c4d850ca8ac1684f7131b778317c0db04de661c7d08321d60c0507868af41fe3150d21b3c6c757367",
"curve_type": "secp256k1"
}
],
"operations": [
{
"operation_identifier": {
"index": 0
},
"type": "TRANSFER",
"account": {
"address": "iowfl-yzooa-br3dt-77erl-nlm7f-kplhq-php75-hw3an-aeqn2-swh4t-3qe",
"sub_account": {
"address": "0000000000000000000000000000000000000000000000000000000000000000"
}
},
"amount": {
"value": "-10",
"currency": {
"symbol": "8",
"decimals": 8
}
}
},
{
"operation_identifier": {
"index": 1
},
"type": "TRANSFER",
"account": {
"address": "xmiu5-jqaaa-aaaag-qbz7q-cai",
"sub_account": {
"address": "0000000000000000000000000000000000000000000000000000000000000000"
}
},
"amount": {
"value": "10",
"currency": {
"symbol": "8",
"decimals": 8
}
}
}
],
"metadata": null
}'