オフチェーン（任意）データ

(async () => {
  const message = "Offline Sign Message Example";
  const signer = 'inj1...'
  const chainId = 'injective-1'
  
  // Sign Arbitrary Data
  const signature = await window.keplr.signArbitrary(chainId, signer, message)
  
  // Verify Arbitrary Data
  const result = await window.keplr.verifyArbitrary(chainId, signer, message, signature)
  
  if (result) {
    console.log("Signature is valid");
  }
})();

import { config } from "dotenv";
import { PrivateKey } from "@injectivelabs/sdk-ts/core/accounts";
import { generateArbitrarySignDoc } from "@injectivelabs/sdk-ts/core/tx";

config();

(async () => {
  const { privateKey } = PrivateKey.generate();
  const injectiveAddress = privateKey.toBech32();
  const publicKey = privateKey.toPublicKey();
  
  const message = "Offline Sign Message Example";
  const { signDocBuff } = generateArbitrarySignDoc(message, injectiveAddress);

  const signature = await privateKey.sign(signDocBuff);
  const signatureInHex = Buffer.from(signature).toString("hex");

  if (
    PrivateKey.verifyArbitrarySignature({
      signature: signatureInHex,
      signDoc: signDocBuff,
      publicKey: publicKey.toHex(),
    })
  ) {
    console.log("Signature is valid");
  }
})();