> ## Documentation Index
> Fetch the complete documentation index at: https://injectivelabs-docs-ai-sdk.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Web3 Gateway 트랜잭션

Indexer에서 트랜잭션 모듈 관련 데이터를 쿼리하는 예제 코드 스니펫입니다. [Web3Gateway](../transactions/web3-gateway/)와 상호작용할 때만 사용됩니다.

## gRPC 사용

### 트랜잭션 준비 응답 조회

```ts theme={null}
import { EvmChainId } from '@injectivelabs/ts-types'
import { Msgs } from '@injectivelabs/sdk-ts/core/modules'
import { getNetworkEndpoints, Network } from '@injectivelabs/networks'
import { IndexerGrpcTransactionApi } from '@injectivelabs/sdk-ts/client/indexer'

const endpoints = getNetworkEndpoints(Network.Testnet)
const indexerGrpcTransactionApi = new IndexerGrpcTransactionApi(endpoints.indexer)

const address = '0x...' // ethereum 주소
const chainId = EvmChainId.Sepolia
const message = { ... } as Msgs
const memo = '...'

const prepareTxResponse = await indexerGrpcTransactionApi.prepareTxRequest({
  address,
  chainId,
  message,
  memo
})

console.log(prepareTxResponse)
```

### Cosmos 트랜잭션 준비 응답 조회

```ts theme={null}
import { getNetworkEndpoints, Network } from '@injectivelabs/networks'
import { IndexerGrpcTransactionApi } from '@injectivelabs/sdk-ts/client/indexer'

const endpoints = getNetworkEndpoints(Network.Testnet)
const indexerGrpcTransactionApi = new IndexerGrpcTransactionApi(endpoints.indexer)

const address = 'inj...'
const message = { ... }

const prepareCosmosTxResponse = await indexerGrpcTransactionApi.prepareCosmosTxRequest({
  address,
  message
})

console.log(prepareCosmosTxResponse)
```

### Web3Gateway Fee Payer 조회

```ts theme={null}
import { getNetworkEndpoints, Network } from "@injectivelabs/networks";
import { IndexerGrpcTransactionApi } from "@injectivelabs/sdk-ts/client/indexer";

const endpoints = getNetworkEndpoints(Network.Testnet);
const indexerGrpcTransactionApi = new IndexerGrpcTransactionApi(
  endpoints.indexer
);

const feePayer = await indexerGrpcTransactionApi.fetchFeePayer();

console.log(feePayer);
```