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DW Spectrum - Hosting an Automated Local HTML PLC Interface

Updated

 

Hosting an Automated Local HTML Panel

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Affected Roles: Administrator, Power Users

Related DW Software: DW Spectrum Professional

Software Version: Client & Server Versions 6.1

Last Edit: March 11, 2026

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Adding a Local HTTP Webpage Item in Spectrum

DW Spectrum Professional’s desktop client software provides users with an intuitive dashboard through which they may monitor camera streams, view playback, and interact with I/O devices for their Site. There are sometimes circumstances where users will have multiple security tools deployed in addition to their DW MEGApix and DW Spectrum products, such as security access panels, door/gate controls, or environmental controls, that are also locally managed.

Rather than having to switch between multiple applications and dashboards to manage a location’s security solutions, Administrators and Power Users can implement the DW Spectrum Client’s Web Pages feature to add a means for viewing and using a local PLC and simplify operations.

This article will provide an example scenario and guidance on the setup process for using Python to create a local HTML webpage such as building management pages, PLC control pages, and more in DW Spectrum Professional.

 

Example Scenario

The Request

An end-user wants to display a locally hosted programmable logic controller (PLC) webpage within DW Spectrum Professional to maintain a "single pane of glass" for the system's users. The customer’s goal is to have operators be able to both view camera video streams and the PLC controls from a single interface, often colloquially referred to as “a single pane of glass”, so that users can monitor and interact with multiple systems without switching applications.

Many PLC control systems provide an HTML interface for display and control including:

  • Door or gate controls
  • Environmental controls
  • Machinery monitoring

 

The Challenge

DW Spectrum allows users to embed web pages into the desktop client interface via a webpage widget. However, for security reasons, Spectrum does not allow loading local HTML files directly (e.g., “file:///” protocol). This restriction exists because allowing arbitrary local file executions could:

  • Expose the client machine to malicious scripts
  • Bypass browser security protections
  • Create privilege escalation risks

In consideration of this obstacle, the following work-around allows local static or dynamic HTML files to be displayed within Spectrum.

 

Setup Process

Part 1: Install Python

  1. Download installer from the official Python website: https://www.python.org/downloads/windows/.

NOTE: “Python” is a general-purpose programming language known for its clear, readable syntax that supports multiple programming models.

IMPORTANT: During installation, you must check the box "Add python.exe to PATH" at the bottom of the installer window before clicking "Install Now."

  1. Run the Python Installation Manager and allow the program to
  2. Once finished, restart the computer to ensure that system variables are updated.

 

Part 2 (Optional): Create the Silent Auto-Launch Script

This configuration allows the web server to run invisibly in the background every time the computer logs in.

Step 1: Create the Server Batch File

  1. Right-click your desktop and select New > Text Document.
  2. Paste the following code:
@echo off
cd C:\Users\DWUSER\Desktop\HTML
python -m http.server 8080
  1. Save this file as "server_start.bat" (ensure it is not saved as .txt).

 

Step 2: Create the Silent Wrapper

  1. Create a second New Text Document on your desktop.
  2. Paste the following line:
CreateObject("Wscript.Shell").Run "server_start.bat", 0, True
  1. Save this file as "RunSilent.vbs".

 

Step 3: Add to Windows Startup

  1. Open the Run (+R) application and enter:
shell:startup
  1. Move both "server_start.bat" and "RunSilent.vbs" into the folder that opens.

 

Part 3: Configure DW Spectrum

  1. Launch the DW Spectrum Client desktop software.
  2. Right-click "Web Pages" in the Resource Tree and select "Add Web Page."
  3. Enter the following:

IMPORTANT: Uncheck the box "Proxy this web page through the server."

  1. Click “OK”.

 

Maintenance Notes

  • To stop the server: Open Task Manager (Ctrl+Shift+Esc), find "Python" in the Background Processes list, and select "End Task."
  • Recommended Persistence: If the files remain in the Startup folder, the server will initialize automatically upon login without displaying a command window.

 

 

 

 

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