Running Web Application Locally

 To create a local-only web application that can still receive patches from outside your network, you can set up a configuration like this:

1. Host the Web Application Locally

• Local Network Hosting: Host the web application on a server or computer accessible only within your internal network. Restrict access to local IP ranges only to ensure that it cannot be accessed from outside.
• Firewall Settings: Set up firewall rules to block external traffic to the app’s port(s). This will prevent any outside access to the app.

2. Set Up an Update Server

To update the local app, you can have a server outside your local network (e.g., on a cloud server) to serve as the patch/update server.

• Patch Server: Host a separate, secure server with patch files and updates. You could use a cloud service or a remote server with restricted access.
• Patch Files: Store updates in a version-controlled system (such as Git) on the patch server. Keep patch files in a directory that your local server can access for downloading.

3. Use a Secure Script to Fetch Updates

• Secure Fetch Script: Set up a script on your local server to periodically check the patch server for new updates. The script could be a cron job (Linux) or Task Scheduler task (Windows) to check for patches and apply them.
• VPN or SSH: Establish a secure VPN or SSH tunnel for the local server to connect to the patch server. This allows only authorized local machines to access patches, maintaining network security.
• Checksum or Signature Verification: Validate the integrity and authenticity of patch files by verifying checksums or using digital signatures.

4. Apply Patches to the Local App

• Once updates are downloaded, automate the patch application to minimize downtime and ensure the app is always up to date. Ensure you have a rollback mechanism to prevent issues in case of failed updates.

Example Setup

1. Patch Server: Git server (on cloud), hosting versioned code and patches.
2. Local Server:
   • Fetch script to connect to Git server for updates.
   • Firewall rules allow access only to the update server’s IP or VPN connection.
   • Apply updates on schedule or manually as needed.

This approach gives you a local-only app with a controlled update process through an external server, ensuring privacy and minimizing external access to your network.