FSDH Redirector Service

A simple static-site toolchain to generate and serve tracked, secure redirects via GitHub Pages.

Purpose

• Maintain a centrally managed list of approved destination URLs in allowed.json.
• Provide an interactive form (generate.html) for users to generate UTM‑tagged redirect links.
• Enforce domain/URL whitelisting in the redirect logic (index.html).
• Track every redirect in Google Analytics before handing off users to the final destination.

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📁 Repository Structure

├── allowed.json          # Whitelist of fully-qualified URLs
├── generate.html         # Interactive redirect‑link generator UI
├── index.html            # Secure redirect page with GA tracking
├── README.md             # This documentation
├── .github/              # CI/CD, linting, security workflows
└── renovate.json         # Dependency update config

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🚀 Quick Start

1. Web Editor: Navigate to this repository on GitHub and press the . key to open the cloud IDE.
2. Add URL: In the web editor, open allowed.json and add your destination URL to the allowed_urls array.
3. Commit & PR: Commit your changes (directly or via a branch) and open a Pull Request against main to approve new URLs.
4. Deploy: Once merged, GitHub Pages will automatically deploy your updates.
5. Generate: Open generate.html to build UTM-tagged redirect links.
6. Track & Redirect: Visitors clicking those links will hit index.html, fire a GA event, then be forwarded to the allowed URL.

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✏️ Adding a New Allowed URL

1. Open allowed.json in the repository root.

2. Add your new, fully URL‑encoded destination to the allowed_urls array:

   {
     "allowed_urls": [
       "https://example.com/page?utm_source=...",
       "https://another.allowed.site/path"
     ]
   }

3. Create a Pull Request targeting main:

   • Title: **Add allowed URL: **<your URL>
   • Body: short description and reason for the redirect.

4. After review and merge, your URL is live and can be used in generate.html.

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🛠 Generating Redirect Links

1. Open generate.html in your browser (e.g. via GitHub Pages).

2. Enter:

   • Destination URL (must match an entry in allowed.json).
   • UTM parameters (source, medium, campaign, etc.).

3. Click Generate Link.

4. The full redirect URL (pointing to index.html?…) is produced and auto‑copied to your clipboard.

5. Share that link in your newsletter, email, or other channels.

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🔒 Secure Redirect Logic

• index.html fetches allowed.json at runtime.
• It rejects any redirect-url not exactly listed in allowed_urls.
• Fires the GA gtag('config',…) call with campaign data.
• Redirects only valid, whitelisted URLs after a short delay.

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📦 Deployment

• Written as a fully static site.
• GitHub Actions workflow (.github/workflows/deploy-static.yml) auto‑deploys on every main push.
• SSL and custom domain support via GitHub Pages settings.