# App Server

{% hint style="info" %}
A React frontend connected to a Node backend is a rock-solid combination for any application.

Connecting React.js to Node.js involves setting up a client-server architecture where React.js serves as the front-end (client) and Node.js serves as the back-end (server) of your application. This allows your React.js application to make requests to the Node.js server to fetch data or perform other server-side operations.
{% endhint %}

{% hint style="danger" %}
The following guide is intended to highlight the flow of requests from the client front-end to the back-end. 

**Please do not modify any files**.
{% endhint %}

<figure><img src="/files/GUZB1Z0NbiUoDpbhskK0" alt=""><figcaption><p>Application Server - Front End / Back End</p></figcaption></figure>

{% tabs %}
{% tab title="Install nano" %}
{% hint style="info" %}
Before you can update the package index or install Vim or Nano, you need to identify the Linux distribution used in the Docker container.
{% endhint %}

1. Log into Portainer either by clicking on the bookmark or&#x20;

   [**https://localhost:9443/#!/auth**](https://localhost:9443/#!/auth)
2. Enter credentials.

<table data-header-hidden><thead><tr><th width="148"></th><th></th></tr></thead><tbody><tr><td>Username</td><td>admin</td></tr><tr><td>Password</td><td>Portainer123</td></tr></tbody></table>

3. Click on 'Live Connect' option.
4. Click on: pdc-fe-1 container

<figure><img src="/files/MgX3nlWMTQuElesyGpEJ" alt=""><figcaption><p>pdc-fe-1</p></figcaption></figure>

5. Exec into the container.

<figure><img src="/files/4X9z0N4hBNBYYDcu3WlW" alt=""><figcaption><p>Exec into pdc-fe-1 container</p></figcaption></figure>

6. Determine the contaner OS.

```bash
cat /etc/os-release
```

7. Install nano.

```bash
apt-get update && apt-get install nano -y

```

<figure><img src="/files/1mJSg7YfuEUEp5IM4aGM" alt=""><figcaption><p>Install nano</p></figcaption></figure>
{% endtab %}

{% tab title="Front End / Back End" %}

#### Front End React

{% hint style="info" %}
One of the main features of React is client-side routing:

In traditional websites, the browser requests a document from a web server, downloads and evaluates CSS and JavaScript assets, and renders the HTML sent from the server. When the user clicks a link, it starts the process all over again for a new page.

Client side routing allows your app to update the URL from a link click without making another request for another document from the server. Instead, your app can immediately render some new UI and make data requests with `fetch` to update the page with new information.
{% endhint %}

x

x
{% endtab %}
{% endtabs %}


---

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Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
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```

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