Query Balances

Learn how to query balances of IBC Cosmos Coins and ERC-20s on Kynno. {synopsis}

This guide will cover the following query methods:

:::warning Note: In this document, the command line is used to interact with endpoints. For dApp developers, using libraries such as cosmjs and cosmos-sdk-js is recommended instead. :::

kynnod & Tendermint RPC

Upon installation and configuration of the Kynno Daemon, developers can query account balances using kynnod with the following CLI command:

$ kynnod query bank balances $KYNNOADDRESS --count-total=$COUNTTOTAL --height=$HEIGHT --output=$OUTPUT --node=$NODE
balances:
- amount: "1000000000000000000"
  denom: akynno
- amount: "100000"
  denom: ibc/ED07A3391A112B175915CD8FAF43A2DA8E4790EDE12566649D0C2F97716B8518
pagination:
  next_key: null
  total: "0"

where:

  • $KYNNOADDRESS is the Kynno address with balances of interest (eg. kynno1...).
  • (optional) $COUNTTOTAL counts the total number of records in all balances to query for.
  • (optional) $HEIGHT is the specific height to query state at (can error if node is pruning state).
  • (optional) $OUTPUT is the output format (eg. text).
  • (optional if running local node) $NODE is the Tendermint RPC node information is requested from (eg. https://tendermint.kynno.dev).

Details of non-native currencies (ie. not akynno) can be queried with the following CLI command:

$ kynnod query erc20 token-pair $DENOM --node=$NODE --height=$HEIGHT --output=$OUTPUT
token_pair:
  contract_owner: OWNER_MODULE
  denom: ibc/ED07A3391A112B175915CD8FAF43A2DA8E4790EDE12566649D0C2F97716B8518
  enabled: true
  erc20_address: 0xFA3C22C069B9556A4B2f7EcE1Ee3B467909f4864

where $DENOM is the denomination of the coin (eg. ibc/ED07A3391A1...).

JSON-RPC

Developers can query account balances of akynno using the eth_getBalance JSON-RPC method in conjunction with curl:

# Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getBalance","params":[`$ETHADDRESS`, `$BLOCK`],"id":1}' -H "Content-Type: application/json" $NODE

# Result
{"jsonrpc":"2.0","id":1,"result":"0x36354d5575577c8000"}

where:

  • $ETHADDRESS is the Etherum hex-address the balance is to be queried from. Note that Kynno addresses (those beginning with kynno1...) can be converte.d to Ethereum addresses using libraries such as kynno-sdk-js.
  • $BLOCK is the block number or block hash (eg. "0x0"). The reasoning for this parameter is due to EIP-1898.
  • (optional if running local node) $NODE is the JSON-RPC node information is requested from (eg. https://mainnet.kynno.network).

Developers can also query account balances of x/erc20-module registered coins using the eth_call JSON-RPC method in conjunction with curl:

# Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_call","params":[{"from":`SENDERCONTRACTADDRESS`, "to":`ERCCONTRACTADDRESS`, "data":`$DATA`}, `$BLOCK`],"id":1}'  -H "Content-Type: application/json" $NODE

# Result
{"jsonrpc":"2.0","id":1,"result":"0x"}

where:

  • $SENDERCONTRACTADDRESS is the Ethereum hex-address this smart contract call is sent from.
  • $ERCCONTRACTADDRESS is the Ethereum hex-address of the ERC-20 contract corresponding to the coin denomination being queried.
  • $DATA is the hash of the balanceof method signature and encoded parameters. balanceOf is a required method in every ERC-20 contract, and the encoded parameter is the address which is having its balance queried. For additional information, see the Ethereum Contract ABI.
  • $BLOCK is the block number or block hash (eg. "0x0"). The reasoning for this parameter is due to EIP-1898.
  • (optional if running local node) $NODE is the JSON-RPC node information is requested from (eg. https://mainnet.kynno.network).

gRPC

Developers can use grpcurl with the AllBalances endpoint to query account balance by address for all denominations:

# Request
grpcurl $OUTPUT -d '{"address":`$KYNNOADDRESS`}' $NODE cosmos.bank.v1beta1.Query/AllBalances

# Result
{
  "balances": [
    {
      "denom": "stake",
      "amount": "1000000000"
    }
  ],
  "pagination": {
    "total": "1"
  }
}

where:

  • $KYNNOADDRESS is the Kynno address with balances of interest (eg. "kynno1...").
  • $NODE is the Cosmos gRPC node information is requested from (eg. https://grpc.kynno.network).
  • (optional) $OUTPUT is the output format (eg. plaintext).

State can also be queried using gRPC within a Go program. The idea is to create a gRPC connection, then use the Protobuf-generated client code to query the gRPC server.

import (
    "context"
    "fmt"

  "google.golang.org/grpc"

    sdk "github.com/cosmos/cosmos-sdk/types"
  "github.com/cosmos/cosmos-sdk/types/tx"
)

func queryState() error {
    myAddress, err := GetKynnoAddressFromBech32("kynno1...") // kynno address with balances of interest.
    if err != nil {
        return err
    }

    // Create a connection to the gRPC server.
    grpcConn := grpc.Dial(
        "https://grpc.kynno.network", // your gRPC server address.
        grpc.WithInsecure(), // the SDK doesn't support any transport security mechanism.
    )
    defer grpcConn.Close()

    // This creates a gRPC client to query the x/bank service.
    bankClient := banktypes.NewQueryClient(grpcConn)
    bankRes, err := bankClient.AllBalances(
        context.Background(),
        &banktypes.QueryAllBalancesRequest{Address: myAddress},
    )
    if err != nil {
        return err
    }

    fmt.Println(bankRes.GetBalances()) // prints the account balances.

    return nil
}

// kynno-sdk-js address converter.
func GetKynnoAddressFromBech32(address string) (string, error) {...}

:::tip Note: The following tools will be useful when using gRPC:

:::