# Subscription

***Github repository:*** [***https://github.com/zetamarkets/sdk/tree/main/examples/subscription***](https://github.com/zetamarkets/sdk/tree/main/examples/subscription)

Subscribing to changes to onchain is easy using `subscription.subscribeProgramAccounts`. In this example we subscribe to any SOL margin account changes, but you can subscribe to any account types you wish to track.

<details>

<summary>Code</summary>

```typescript
require("dotenv").config();

import {
  Exchange,
  Network,
  utils,
  types,
  programTypes,
  subscription,
  constants,
} from "@zetamarkets/sdk";

import { PublicKey, Connection } from "@solana/web3.js";

const NETWORK_URL = process.env["network_url"]!;

let network: Network;

switch (process.env["network"]) {
  case "localnet":
    network = Network.LOCALNET;
    break;
  case "devnet":
    network = Network.DEVNET;
    break;
  case "mainnet":
    network = Network.MAINNET;
    break;
  default:
    throw Error("Unsupported network type!");
}

async function main() {
  // Create a solana web3 connection to devnet.
  const connection = new Connection(NETWORK_URL, "confirmed");

  const loadExchangeConfig = types.defaultLoadExchangeConfig(
    network,
    connection,
    utils.defaultCommitment(),
    0, // ThrottleMs - increase if you are running into rate limit issues on startup.
    true
  );

  await Exchange.load(
    loadExchangeConfig,
    // Exchange wallet can be ignored for normal clients.
    undefined
  );

  subscription.subscribeProgramAccounts<programTypes.CrossMarginAccount>(
    types.ProgramAccountType.CrossMarginAccount,
    async (
      data: subscription.AccountSubscriptionData<programTypes.CrossMarginAccount>
    ) => {
      // Here you can filter for only accounts you care about (such as your own)
      console.log(data);
    }
  );

  await utils.sleep(100_000);

  // Close to end the websockets.
  // await Exchange.close();
}

main().catch(console.error.bind(console));
```

</details>


---

# 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.zeta.markets/build-with-zeta/sdks/typescript-sdk/examples/subscription.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.