> For the complete documentation index, see [llms.txt](https://docs.flashback.tech/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.flashback.tech/support-reference/supported-sdks/cloud-storage/google-gcs/node.js-with-custom-endpoint.md).

# Node.js with custom endpoint

```typescript
import { Storage } from '@google-cloud/storage';
import { FlashgateGCSStorage } from '@flashgatetech/flashgateclient/gcs';

const config = {
    apiEndpoint: process.env.TEST_GCS_AWS_PROVIDER_URL,
    tokenUri: process.env.TEST_GCS_AWS_PROVIDER_URL + '/token',
    credentials: {
      client_email: process.env.TEST_GCS_CLIENT_EMAIL!,
      private_key: process.env.TEST_GCS_PRIVATE_KEY,
    },
  },
}

// Use custom auth client with custom token endpoint
const tokenUri = config.tokenUri || `${config.apiEndpoint}/token`;
const authClient = new FlashgateAuthClient(
  tokenUri,
  config.credentials,
  [
    'https://www.googleapis.com/auth/devstorage.full_control',
    'https://www.googleapis.com/auth/devstorage.read_only',
    'https://www.googleapis.com/auth/devstorage.read_write'
  ]
);

const storage = new Storage({
  apiEndpoint: config.apiEndpoint,
  authClient,
  useAuthWithCustomEndpoint: true,
});

const bucket = storage.bucket(bucketName);

// 1. Check if bucket exists
try {
  const [exists] = await storage.bucket(bucketName).exists();
  expect(exists).toBe(true);
} catch (error) {
  console.error('Error checking bucket existence:', error);
  throw error;
}
```


---

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