Get Address / Public Key

The getKey function is used to retrieve addresses and its associated public key. This function is a crucial part of interacting with blockchain accounts, enabling developers to obtain account details securely.

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Function Signature

getKey(chainId: string): Promise<Key>

Parameters

• chainId (string): The unique identifier of the blockchain chain from which the key information should be retrieved.
  • Cosmos-based chainIds (e.g., cosmoshub-4)
  • EVM-based chainIds (e.g., eip155:1)
  • Starknet chainIds (e.g., starknet:SN_MAIN)

If the webpage has the necessary permissions to access the key and Keplr is unlocked, invoking getKey will return the address and public key with information aside in the following structure:

Return Type

interface Key {
  readonly name: string;
  readonly algo: string;
  readonly pubKey: Uint8Array;
  readonly address: Uint8Array;
  readonly bech32Address: string;
  readonly ethereumHexAddress: string;
  readonly isNanoLedger: boolean;
  readonly isKeystone: boolean;
}

Key Properties Table

Property	Type	Description
name	string	The name of the currently selected key store. This is a descriptive label set by the user.
algo	string	The algorithm used to generate the key (e.g., secp256k1).
pubKey	Uint8Array	The public key of the account, provided in binary format (Uint8Array).
address	Uint8Array	The account address, represented in binary format (Uint8Array).
bech32Address	string	The Bech32-encoded address, commonly used in Cosmos-based blockchains.
ethereumHexAddress	string	The Ethereum-compatible address, formatted as a hexadecimal string.
isNanoLedger	boolean	Indicates whether the selected account is from a Ledger Nano hardware wallet.
isKeystone	boolean	Indicates whether the selected account is from a Keystone hardware wallet.

info

Hardware Wallet Support:

• Ledger wallets typically use the Amino JSON sign mode due to limited support for Protobuf-based SIGN_MODE_DIRECT. Check more details here.
• Use the isNanoLedger and isKeystone properties to determine the appropriate signing mode for hardware wallets.

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Example Usage

Here’s an example of how to use the getKey function:

Cosmos-based chain

(async () => {
  try {
    const chainId = "cosmoshub-4";
    const key = await getKey(chainId);

    console.log("Account Name:", key.name);
    console.log("Public Key (Hex):", Buffer.from(key.pubKey).toString("hex"));
    console.log("Bech32 Address:", key.bech32Address);
    console.log("Ethereum Address:", key.ethereumHexAddress);
    console.log("Is from Ledger:", key.isNanoLedger);
  } catch (error) {
    console.error("Error retrieving key:", error);
  }
})();

EVM-based chain

(async () => {
  try {
    const chainId = "eip155:1"; // e.g., Ethereum Mainnet
    const key = await getKey(chainId);

    console.log("Account Name:", key.name);
    console.log("Public Key (Hex):", Buffer.from(key.pubKey).toString("hex"));
    console.log("Ethereum Address:", key.ethereumHexAddress);
    console.log("Is from Ledger:", key.isNanoLedger);
  } catch (error) {
    console.error("Error retrieving key:", error.message);
  }
})();