queryNetwork_genesisConfiguration - Cardano

Example code for the queryNetwork_genesisConfiguration JSON-RPC method. Complete guide on how to use queryNetwork_genesisConfiguration JSON-RPC in GetBlock Web3 documentation.

This method returns the genesis configuration for a given era. The configuration holds the constants an era was initialized with, such as the network magic and slot parameters.

Parameters

Parameter	Type	Required	Description
era	string	No	The era to read genesis for: byron, shelley, alonzo, or conway

Request

cURL

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "queryNetwork/genesisConfiguration",
    "params": {
        "era": "shelley"
    },
    "id": "getblock.io"
}'

JavaScript

example.js

const response = await fetch(
    'https://go.getblock.io/<ACCESS-TOKEN>/',
    {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({"jsonrpc": "2.0", "method": "queryNetwork/genesisConfiguration", "params": {"era": "shelley"}, "id": "getblock.io"})
    }
);
console.log(await response.json());

Python

example.py

import requests

response = requests.post(
    'https://go.getblock.io/<ACCESS-TOKEN>/',
    headers={'Content-Type': 'application/json'},
    json={"jsonrpc": "2.0", "method": "queryNetwork/genesisConfiguration", "params": {"era": "shelley"}, "id": "getblock.io"}
)

print(response.json())

Response

{
    "jsonrpc": "2.0",
    "method": "queryNetwork/genesisConfiguration",
    "result": {
        "era": "shelley",
        "startTime": "2017-09-23T21:44:51Z",
        "networkMagic": 764824073,
        "network": "mainnet",
        "activeSlotsCoefficient": "1/20",
        "securityParameter": 2160,
        "epochLength": 432000,
        "slotsPerKesPeriod": 129600,
        "maxKesEvolutions": 62,
        "slotLength": {
            "milliseconds": 1000
        },
        "updateQuorum": 5,
        "maxLovelaceSupply": 45000000000000000,
        "initialParameters": {
            "minFeeCoefficient": 44,
            "minFeeConstant": {
                "ada": {
                    "lovelace": 155381
                }
            },
            "maxBlockBodySize": {
                "bytes": 65536
            },
            "maxBlockHeaderSize": {
                "bytes": 1100
            },
            "maxTransactionSize": {
                "bytes": 16384
            },
            "stakeCredentialDeposit": {
                "ada": {
                    "lovelace": 2000000
                }
            },
            "stakePoolDeposit": {
                "ada": {
                    "lovelace": 500000000
                }
            },
            "stakePoolRetirementEpochBound": 18,
            "desiredNumberOfStakePools": 150,
            "stakePoolPledgeInfluence": "3/10",
            "minStakePoolCost": {
                "ada": {
                    "lovelace": 340000000
                }
            },
            "monetaryExpansion": "3/1000",
            "treasuryExpansion": "1/5",
            "federatedBlockProductionRatio": "1/1",
            "extraEntropy": "neutral",
            "minUtxoDepositConstant": {
                "ada": {
                    "lovelace": 1000000
                }
            },
            "minUtxoDepositCoefficient": 0,
            "version": {
                "major": 2,
                "minor": 0
            }
        },
        "initialDelegates": [
            {
                "issuer": {
                    "id": "162f94554ac8c225383a2248c245659eda870eaa82d0ef25fc7dcd82"
                },
                "delegate": {
                    "id": "4485708022839a7b9b8b639a939c85ec0ed6999b5b6dc651b03c43f6",
                    "vrfVerificationKeyHash": "aba81e764b71006c515986bf7b37a72fbb5554f78e6775f08e384dbd572a4b32"
                }
            },
            {
                "issuer": {
                    "id": "b9547b8a57656539a8d9bc42c008e38d9c8bd9c8adbb1e73ad529497"
                },
                "delegate": {
                    "id": "855d6fc1e54274e331e34478eeac8d060b0b90c1f9e8a2b01167c048",
                    "vrfVerificationKeyHash": "66d5167a1f426bd1adcc8bbf4b88c280d38c148d135cb41e3f5a39f948ad7fcc"
                }
            },
            {
                "issuer": {
                    "id": "f7b341c14cd58fca4195a9b278cce1ef402dc0e06deb77e543cd1757"
                },
                "delegate": {
                    "id": "69ae12f9e45c0c9122356c8e624b1fbbed6c22a2e3b4358cf0cb5011",
                    "vrfVerificationKeyHash": "6394a632af51a32768a6f12dac3485d9c0712d0b54e3f389f355385762a478f2"
                }
            }
        ],
        "initialFunds": {},
        "initialStakePools": {
            "stakePools": {},
            "delegators": {}
        }
    },
    "id": "getblock.io"
}

Response Parameters

Field	Type	Description
networkMagic	integer	Network magic identifying the network
network	string	Network name, mainnet or testnet
epochLength	integer	Number of slots in an epoch
securityParameter	integer	The security parameter k
maxLovelaceSupply	integer	Maximum total supply in lovelace

Use Cases

• Parameter Bootstrapping: Read genesis constants when initializing a client

• Network Detection: Confirm the network magic before submitting transactions

• Slot Math: Use epoch length and slot length for time conversions

• Supply Modeling: Read the maximum lovelace supply for issuance models

Error Handling

Error Code	Message	Description
-32602	Invalid params	A required field is missing or has the wrong type
-32000	Query unavailable	The query is not available in the current ledger era
-32603	Internal error	The node failed to answer the query