> For the complete documentation index, see [llms.txt](https://docs.expand.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.expand.network/how-to/stream-data-websocket/stream-trade.md).

# Stream Trade

Stream trade is a method used to obtain the prices of a specific pair of tokens across multiple decentralized exchanges (DEXs).\
(Currently Available for Ethereum Only)

### Response Schema: 

| Field    | Description                     |
| -------- | ------------------------------- |
| type     | Type of transaction.            |
| platform | Specific name of  DEX platform. |
| symbol   | Token pair.                     |
| price    | Price of token pair.            |

### Streaming trades:

Users can stream trades in two ways:

#### Example 1: via wscat script (For Linux based distro)

First, the user needs to run the following command in their terminal to install wscat in their system: 

```shell
npm install -g wscat 
```

After installing wscat, the user needs to create a shell script and paste the following sample code:

**Client Side Sample Socket Code** :

```shell
#!/bin/bash

echo "Price Discovery\n"
read -p "x-api-key: " YOUR_API_KEY
wscat -c wss://pricediscovery.expand.network -H authorization:secret-token -H x-api-key:$YOUR_API_KEY
```

{% hint style="info" %}
Once the file has been saved, the user will need to grant permission for it to be executed. This can be accomplished by executing the following command:
{% endhint %}

```bash
chmod +x YOUR_FILE_NAME.sh
```

After following the above steps, the user needs to run the file. This can be done by entering the filename in the console.

**Executing a query**: 

After executing the aforementioned file(shell script), the user will be prompted to input the appropriate API key.

After entering the API key, the user can subscribe to the following actions:

```shell
{"action": "streamTrade"}
```

{% hint style="info" %}
Make sure you are connected to the WebSocket before you perform the following queries. 
{% endhint %}

**Applying a filter in the query**: 

Users can apply the following filters in their query:-

* token0
* token1

**The above filters can be applied in any combination, using the following syntax**: 

```shell
{"action": "streamTrade", "token0": "token_address", "token1": "token_address" }
```

**Sample Query**:

```shell
{"action": "streamTrade", "token0": "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2", "token1": "0xdAC17F958D2ee523a2206206994597C13D831ec7" }
```

#### Example 2. via javascript code

First, the user needs to run the following command in their terminal to install wscat in their system: 

```shell
npm i ws
```

After installing ws, the user needs to run the following sample code on their device to start streaming: 

**Client Side Sample Socket Code** :

```javascript
const WebSocket = require('ws');
const url = 'wss://pricediscovery.expand.network';
const options = {
  headers: {
    Authorization: 'secret-token',
    'x-api-key': 'YOUR_API_KEY', // Replace this with your API Key
  }
};

const ws = new WebSocket(url, options);

ws.on('open', () => {
  console.log('WebSocket connection established.');
  const payload = {
    action: "streamTrade",
    token0: "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
    token1: "0xdAC17F958D2ee523a2206206994597C13D831ec7"
  };
  ws.send(JSON.stringify(payload));
});


ws.on('message', (data) => {
  console.log(`Received data: ${data}`);
});

ws.on('close', () => {
  console.log('WebSocket connection closed.');
});
```

{% hint style="info" %}
The payload can be modified, depending on the action.
{% endhint %}

### Expected Output:

```javascript
{
  "type": "DEX",
  "platform": "UniswapV2",
  "symbol": "ETHUSDT",
  "price": "1731798672"
}
```

### How to disconnect: 

To disconnect from our API, enter `ctrl-c`  in the connected console.