# Javascript

{% hint style="warning" %}
The documentation is designed for Liker Land and LikeCoin v2. For information on [3ook.com](https://3ook.com/) and LikeCoin v3, please visit [docs.3ook.com](https://docs.3ook.com) and [dao.like.co](https://dao.like.co/).
{% endhint %}

### Encode and Sign Raw Message

The parameters should consist with your account information. The `accountNumber` and `sequence` could be found by querying LCD `/cosmos/auth/v1beta1/accounts/{fromAddress}` endpoint.

```javascript
const secp256k1 = require('secp256k1');
const createHash = require('create-hash');
const Long = require('long');
const { MsgSend } = require("./build/codec/cosmos/bank/v1beta1/tx");
const { TxBody, AuthInfo, SignDoc, TxRaw } = require("./build/codec/cosmos/tx/v1beta1/tx");
const { PubKey } = require("./build/codec/cosmos/crypto/secp256k1/keys");

// define parameters
const chainId = "likechain-local-testnet";
const privateKey = "69b4e47d3aa61ad6184493529cd0feb0d2dfb55ea31aa9799af42607de3cd1a9";
const publicKey = "A4Fj1Y4k77Qaxuy496CHYB2rpfWXkM3LCnlyrU8eKbH7";
const accountNumber = 2;
const fromAddress = "cosmos1lsagfzrm4gz28he4wunt63sts5xzmczw8pkek3";
const toAddress = "cosmos1mnyn7x24xj6vraxeeq56dfkxa009tvhgknhm04";
const tokenAmount = 1000000;
const memo = "Enjoy your money";
const gasLimit = 100000;
const sequence = 17;

const messages = [{
  typeUrl: "/cosmos.bank.v1beta1.MsgSend",
  value: {
    fromAddress,
    toAddress,
    amount: [
      {
        denom: "nanolike",
        amount: tokenAmount.toString(),
      },
    ],
  }
}];

const wrappedMessages = messages.map(msg => {
  return {
    typeUrl: msg.typeUrl,
    value: MsgSend.encode(msg.value).finish(),
  }
})

const body = {
  typeUrl: "/cosmos.tx.v1beta1.TxBody",
  value: {
    memo,
    messages: wrappedMessages,
    timeoutHeight: Long.UZERO,
    extensionOptions: [],
    nonCriticalExtensionOptions: [],
  },
}
const bodyBytes = TxBody.encode(body.value).finish();

const pubkeyBytes = PubKey.encode({ key: publicKey }).finish();

const authInfo = {
  signerInfos: [
    {
      sequence: Long.fromNumber(sequence),
      publicKey: {
        typeUrl: "/cosmos.crypto.secp256k1.PubKey",
        value: pubkeyBytes,
      },
      modeInfo: {
        single: {
          mode: 1,
        },
      },
    },
  ],
  fee: {
    gasLimit: Long.fromNumber(gasLimit),
    payer: "",
    granter: "",
    amount: [
      {
        denom: "nanolike",
        amount: "0",
      },
    ],
  },
}

const authInfoBytes = AuthInfo.encode(authInfo).finish();
const signDoc = {
  bodyBytes,
  authInfoBytes,
  chainId,
  accountNumber: Long.fromNumber(accountNumber),
}
const signBytes = SignDoc.encode(signDoc).finish();

const privkeyBytes = Buffer.from(privateKey, 'hex')

const sign = (msg, privateKey) => {
  const msgSha256 = createHash('sha256');
  msgSha256.update(msg);
  const msgHash = msgSha256.digest();
  const { signature: signatureArr } = secp256k1.ecdsaSign(msgHash, privateKey);
  const signature = Buffer.from(signatureArr)
  return signature;
}
const signatureBytes = sign(signBytes, privkeyBytes);

const tx = {
  bodyBytes,
  authInfoBytes,
  signatures: [signatureBytes],
}
​
const txBytes = TxRaw.encode(tx).finish();
​
console.log("signature_bytes:", signatureBytes.toString('base64'));
console.log("sign_bytes:", signBytes.toString('base64'));
console.log("tx_bytes:", txBytes.toString('base64'));

// signature_bytes: zIfF132OINwGz0psHn+nxeYVQdHZXiqO/94qaXrowcRFEL2jA0qFarz22VBXYXQudOV6y0BL84/m475awNkiFA==
// sign_bytes: CqgBCpMBChwvY29zbW9zLmJhbmsudjFiZXRhMS5Nc2dTZW5kEnMKLWNvc21vczFsc2FnZnpybTRnejI4aGU0d3VudDYzc3RzNXh6bWN6dzhwa2VrMxItY29zbW9zMW1ueW43eDI0eGo2dnJheGVlcTU2ZGZreGEwMDl0dmhna25obTA0GhMKCG5hbm9saWtlEgcxMDAwMDAwEhBFbmpveSB5b3VyIG1vbmV5EmcKUApGCh8vY29zbW9zLmNyeXB0by5zZWNwMjU2azEuUHViS2V5EiMKIQOBY9WOJO+0GsbsuPegh2Adq6X1l5DNywp5cq1PHimx+xIECgIIARgREhMKDQoIbmFub2xpa2USATAQoI0GGhdsaWtlY2hhaW4tbG9jYWwtdGVzdG5ldCAC
// tx_bytes: CqgBCpMBChwvY29zbW9zLmJhbmsudjFiZXRhMS5Nc2dTZW5kEnMKLWNvc21vczFsc2FnZnpybTRnejI4aGU0d3VudDYzc3RzNXh6bWN6dzhwa2VrMxItY29zbW9zMW1ueW43eDI0eGo2dnJheGVlcTU2ZGZreGEwMDl0dmhna25obTA0GhMKCG5hbm9saWtlEgcxMDAwMDAwEhBFbmpveSB5b3VyIG1vbmV5EmcKUApGCh8vY29zbW9zLmNyeXB0by5zZWNwMjU2azEuUHViS2V5EiMKIQOBY9WOJO+0GsbsuPegh2Adq6X1l5DNywp5cq1PHimx+xIECgIIARgREhMKDQoIbmFub2xpa2USATAQoI0GGkDMh8XXfY4g3AbPSmwef6fF5hVB0dleKo7/3ippeujBxEUQvaMDSoVqvPbZUFdhdC505XrLQEvzj+bjvlrA2SIU
```

### Commit a Transaction

Put the `tx_bytes` from above step in the JSON request body as below, and post the LCD`/cosmos/tx/v1beta1/txs` endpoint.

```javascript
{
  "tx_bytes": "Your tx bytes here",
  "mode": "BROADCAST_MODE_SYNC"
}
```

For details of the [`POST /txs`](/developer/likecoin-chain-api/rpc-api.md#post-txs) and other chain RPC API, please refer to the [LikeCoin chain RPC API section](/developer/likecoin-chain-api/rpc-api.md).

### Verify Transaction Signature

```javascript
const secp256k1 = require('secp256k1');
const createHash = require('create-hash');

const publicKey = Buffer.from("A4Fj1Y4k77Qaxuy496CHYB2rpfWXkM3LCnlyrU8eKbH7", "base64");
const signature = Buffer.from("zIfF132OINwGz0psHn+nxeYVQdHZXiqO/94qaXrowcRFEL2jA0qFarz22VBXYXQudOV6y0BL84/m475awNkiFA==", "base64");
const signBytes = Buffer.from("CqgBCpMBChwvY29zbW9zLmJhbmsudjFiZXRhMS5Nc2dTZW5kEnMKLWNvc21vczFsc2FnZnpybTRnejI4aGU0d3VudDYzc3RzNXh6bWN6dzhwa2VrMxItY29zbW9zMW1ueW43eDI0eGo2dnJheGVlcTU2ZGZreGEwMDl0dmhna25obTA0GhMKCG5hbm9saWtlEgcxMDAwMDAwEhBFbmpveSB5b3VyIG1vbmV5EmcKUApGCh8vY29zbW9zLmNyeXB0by5zZWNwMjU2azEuUHViS2V5EiMKIQOBY9WOJO+0GsbsuPegh2Adq6X1l5DNywp5cq1PHimx+xIECgIIARgREhMKDQoIbmFub2xpa2USATAQoI0GGhdsaWtlY2hhaW4tbG9jYWwtdGVzdG5ldCAC", "base64");
const msgSha256 = createHash('sha256');
msgSha256.update(signBytes);
const msgHash = msgSha256.digest();
console.log(secp256k1.ecdsaVerify(signature, msgHash, publicKey));

// true
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.v2.like.co/developer/likecoin-chain-api/sample/javascript.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.