Technical ramblings - Exposing Local Applications: Cloudflare and Gradio Tunnels

When developing or testing applications locally, you may need to share them quickly over the internet. Whether it’s for demos, hackathons, or collaborative projects, tunneling tools like Cloudflare’s TryCloudflare and Gradio’s Share Feature provide effective solutions to expose local services to the public.

This guide focuses on setting up tunnels for various workloads (e.g., web services, web apps, TGI servers, VLLM services) and provides detailed steps for using these tools. The examples assume your service is running locally on a specific port (e.g., http://localhost:8080).

Cloudflare’s TryCloudflare

Cloudflare’s TryCloudflare lets you quickly expose local services to the internet with no Cloudflare account required. While it’s intended for testing or temporary use, Cloudflare also offers premium tunnels for production-grade needs.

Why Use Cloudflare?

Quick Setup: A single command is enough to expose your service.
Secure: It uses Cloudflare’s global network, protecting your IP address.
Temporary Usage: Ideal for demos or quick sharing during development.

Setting Up TryCloudflare

Install cloudflared:

sudo apt update
sudo apt install -y wget
wget https://github.com/cloudflare/cloudflared/releases/latest/download/cloudflared-linux-amd64.deb
sudo dpkg -i cloudflared-linux-amd64.deb

Expose a Local Service (replace 8080 with your service’s port):
```
cloudflared tunnel --url http://localhost:8080
```
Share the Public URL:

After running the command, you’ll receive a public URL like:
```
https://<random-subdomain>.trycloudflare.com
```
This link is temporary and only works while the cloudflared process is running.

Example Workloads:

Web Service: Start your web service (e.g., Flask, FastAPI, Node.js) locally on port 8080 and use cloudflared to expose it.
TGI or VLLM Server: Run your inference server locally, bound to a port, and use cloudflared to expose it for collaborators or clients to test.

For Production Use:

For permanent, production-grade tunnels with custom domains, better reliability, and SLAs, consider upgrading to Cloudflare’s premium tunnel services.

Gradio’s Share Feature

Gradio is widely used for creating interfaces for machine learning models, but its share=True option can also be repurposed to expose general-purpose applications.

Why Use Gradio?

Ease of Use: Designed for developers, with minimal configuration required.
Temporary Links: Ideal for demos, with links valid for up to 72 hours.
Integrated with Python: Perfect for exposing Python-based services.

Setting Up Gradio Tunnels

Install Gradio:
```
pip install gradio
```

Expose a Local Service:

Create a minimal Gradio app to expose your service (replace 8080 with your service’s port):

import gradio as gr

def expose_app():
    return "Service running on http://localhost:8080"

demo = gr.Interface(fn=expose_app, inputs=[], outputs="text")
demo.launch(share=True)

Share the Public URL:

Running the script provides a public URL like:
```
https://<random-subdomain>.gradio.live
```
This link is active for 72 hours.

Example Workloads:

Web Service: Use Gradio to describe and share your web service running on localhost:8080.
Web App: Expose your local React, Vue, or other frontend applications by sharing the port they’re hosted on.
Inference Servers: Provide lightweight interaction interfaces for machine learning models.

For Production Use:

Gradio’s share links are temporary and not intended for production. For permanent hosting, consider deploying on platforms like Hugging Face Spaces.

Recommendations and When to Use

Cloudflare TryCloudflare: Best for quick exposure of services without additional Python dependencies. Use it for secure sharing during hackathons or short-lived projects. For production or long-term use, consider Cloudflare’s premium tunnels.
Gradio Share Feature: Ideal for Python developers or when you need a simple interface to accompany your service. Use it to share ML demos, Python apps, or lightweight experiments.

Both tools are great for development and testing but remember their limitations for production-grade usage. Choose based on your workflow and requirements.

This guide equips you with two powerful tools to expose local applications to the world, simplifying collaboration and testing. Happy sharing!