> For the complete documentation index, see [llms.txt](https://docs.getblock.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.getblock.io/api-reference/midnight/system_syncstate-midnight.md).

# system\_syncState - Midnight

Example code for the system\_syncState JSON-RPC method. Complete guide on how to use system\_syncState JSON-RPC in GetBlock Web3 documentation.

This method returns the node's synchronization state, including the block it started from, the block it has reached, and the highest known block on the network.

## Parameters

* None

## Request Example

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

```bash
curl --location --request POST 'https://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "system_syncState",
    "params": [],
    "id": "getblock.io"
}'
```

{% endtab %}

{% tab title="JavaScript (Axios)" %}

```javascript
import axios from 'axios';

const data = JSON.stringify({
    "jsonrpc": "2.0",
    "method": "system_syncState",
    "params": [],
    "id": "getblock.io"
});

const config = {
    method: 'post',
    url: 'https://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/',
    headers: {
        'Content-Type': 'application/json'
    },
    data: data
};

axios(config)
    .then(response => console.log(JSON.stringify(response.data, null, 2)))
    .catch(error => console.log(error));
```

{% endtab %}

{% tab title="Python (Requests)" %}

```python
import requests
import json

url = "https://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/"

payload = json.dumps({
    "jsonrpc": "2.0",
    "method": "system_syncState",
    "params": [],
    "id": "getblock.io"
})

headers = {
    'Content-Type': 'application/json'
}

response = requests.post(url, headers=headers, data=payload)
print(response.text)
```

{% endtab %}

{% tab title="Rust (Reqwest)" %}

```rust
use reqwest::Client;
use serde_json::json;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();

    let payload = json!({
        "jsonrpc": "2.0",
        "method": "system_syncState",
        "params": [],
        "id": "getblock.io"
});

    let response = client
        .post("https://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&payload)
        .send()
        .await?;

    let result: serde_json::Value = response.json().await?;
    println!("{:#?}", result);

    Ok(())
}
```

{% endtab %}
{% endtabs %}

## Response Example

```json
{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": {
        "startingBlock": 657521,
        "currentBlock": 967344,
        "highestBlock": 967344
    }
}
```

## Response Parameters

| Field                | Type    | Description                                    |
| -------------------- | ------- | ---------------------------------------------- |
| result.startingBlock | integer | Block number at which the node started syncing |
| result.currentBlock  | integer | Block number the node has synced up to         |
| result.highestBlock  | integer | Highest block known to the network             |

## Use Cases

* Detecting whether a node is behind the tip
* Computing sync progress as `(currentBlock - startingBlock) / (highestBlock - startingBlock)`
* Monitoring dashboards and alerting on lagging nodes

## Error Handling

| Status Code | Error Message     | Cause                                       |
| ----------- | ----------------- | ------------------------------------------- |
| 403         | Forbidden         | Missing or invalid `<ACCESS-TOKEN>`         |
| -32602      | Invalid params    | Request parameters are missing or malformed |
| 429         | Too Many Requests | Rate limit exceeded for your plan           |

## SDK Integration

{% tabs %}
{% tab title="@polkadot/api (JavaScript)" %}

```javascript
import { ApiPromise, WsProvider } from '@polkadot/api';

const wsProvider = new WsProvider('wss://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/');
const api = await ApiPromise.create({ provider: wsProvider });

// Call via the typed API:
const result = await api.rpc.system.syncState();
console.log(result.toJSON());

// Or call the raw JSON-RPC method:
const raw = await api.rpc.rpc.methods();
// const raw = await (api as any)._rpcCore.provider.send('system_syncState', []);
```

{% endtab %}

{% tab title="substrate-interface (Python)" %}

```python
from substrateinterface import SubstrateInterface

substrate = SubstrateInterface(url='wss://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/')

# Generic RPC call:
result = substrate.rpc_request('system_syncState', [])
print(result)
```

{% endtab %}
{% endtabs %}