# signatureSubscribe

Subscribe to receive a notification when the transaction with the given signature reaches the specified commitment level.

{% hint style="danger" %}
This is a subscription to a single notification. It is automatically cancelled by the server once the notification, `signatureNotification`, is sent by the RPC.
{% endhint %}

#### Parameters required for this RPC call

* The transaction signature, as base-58 encoded string. The transaction signature must be the first signature from the transaction (see [transaction id](https://solana.com/docs/references/terminology#transaction-id) for more details).
* **configuration object**: This contains the following parameters, all are optional fields.
  * **commitment**: The commitment describes how finalized a block is at that point in time. Commitment levels <mark style="color:yellow;">processed</mark>, <mark style="color:yellow;">confirmed</mark> and <mark style="color:yellow;">finalized</mark> are supported, defaults to <mark style="color:yellow;">finalized</mark>.
  * **enableReceivedNotification**: Whether or not to subscribe for notifications when signatures are received by the RPC, in addition to when they are processed.

{% tabs %}
{% tab title="Websocket" %}

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "signatureSubscribe",
  "params": [
    "2EBVM6cB8vAAD93Ktr6Vd8p67XPbQzCJX47MpReuiCXJAtcjaxpvWpcg9Ege1Nr5Tk3a2GFrByT7WPBjdsTycY9b",
    {
      "commitment": "finalized",
      "enableReceivedNotification": false
    }
  ]
}
```

{% endtab %}

{% tab title="Response" %}

```json
{
  "jsonrpc": "2.0",
  "result": 0, //required to unsubscribe
  "id": 1
}
```

{% endtab %}
{% endtabs %}

**Notification Format:**

The notification will be an RpcResponse JSON object with value containing an object with:

* `slot: <u64>` - The corresponding slot.
* `value: <object|string>` - a notification value of [`RpcSignatureResult`](https://github.com/solana-labs/solana/blob/6d28fd455b07e3557fc6c0c3ddf3ba03e3fe8482/rpc-client-api/src/response.rs#L265-L268), resulting in either:
  * when `enableReceivedNotification` is `true` and the signature is received: the literal string [`"receivedSignature"`](https://github.com/solana-labs/solana/blob/6d28fd455b07e3557fc6c0c3ddf3ba03e3fe8482/rpc-client-api/src/response.rs#L286-L288), or
  * when the signature is processed: `err: <object|null>`:
    * `null` if the transaction succeeded in being processed at the specified commitment level, or
    * a [`TransactionError`](https://github.com/solana-labs/solana/blob/6d28fd455b07e3557fc6c0c3ddf3ba03e3fe8482/sdk/src/transaction/error.rs#L15-L164), if the transaction failed

**Examples Responses:**&#x20;

{% tabs %}
{% tab title="Successfully Processed Transaction" %}

```json
{
  "jsonrpc": "2.0",
  "method": "signatureNotification",
  "params": {
    "result": {
      "context": {
        "slot": 5207624
      },
      "value": {
        "err": null
      }
    },
    "subscription": 24006
  }
}
```

{% endtab %}

{% tab title="Successfully received transaction Signature" %}

```json
{
  "jsonrpc": "2.0",
  "method": "signatureNotification",
  "params": {
    "result": {
      "context": {
        "slot": 5207624
      },
      "value": "receivedSignature"
    },
    "subscription": 24006
  }
}
```

{% endtab %}
{% endtabs %}