# Stream Gas

Stream Gas is a method used to obtain the gas fees given by a public address.

### Response Schema: 

| Field        | Description                                                                                            |
| ------------ | ------------------------------------------------------------------------------------------------------ |
| address      | The public address that is subscribed for Gas Streaming                                                |
| blockNumber  | The BlockNumber where the Transaction Occured.                                                         |
| currentPrice | The Current Price for ETH (in USD).                                                                    |
| gas          | The Gas Object that consists of totalGasUsed and the transactionList with the Current Price (in cents) |

### Streaming Gas:

Users can stream gas 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 needs 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": "streamGas"}
```

{% 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:-

* addresses

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

```shell
{"action":"streamGas","addresses":["address1" , "address2" , ...]}
```

**Sample Query**:

```shell
{"action":"streamGas","addresses":["0x690B9A9E9aa1C9dB991C7721a92d351Db4FaC990"]}
```

#### 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: "streamGas",
    addresses: ["0x690B9A9E9aa1C9dB991C7721a92d351Db4FaC990"]
  };
  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
"blockNumber": 17336355,
"currentPrice": "1799.59",
"gas": {
"totalFeesSpent": 41231312312212312,
"transactionList": {
"0x7a29adcfad36eb70c1fb1b7b15b7779ac347c41a758ac13bade5627d1afb3379": 41231312312212312
},
"totalCurrentPrice": "7480"
}}
```

### How to disconnect: 

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