uTPro URL Viewer for Umbraco

Fetch any URL from inside the Umbraco backoffice and see exactly what a search engine or browser sees — redirect chain, response headers, HTML source, and a full static analysis including a composite SEO score.

Supports Umbraco 16, 17 and 18.

What it does

Installing this package adds a URL Viewer section to the backoffice navigation. Users assigned to the section get a single URL Viewer tab.

URL Viewer tab

Enter any URL, pick the scheme (HTTP/HTTPS), user agent and referrer, then fetch. You get:

• Full redirect chain — every hop with status code and raw response headers.
• HTML source viewer — line numbers, word-wrap toggle, copy-to-clipboard, spam-word highlighting.
• Composite SEO score (0–100) — Lighthouse-style checklist with per-category sub-scores (SEO / Technical / Content / Accessibility) and individual check pass/fail + remediation advice.
• On-page SEO analysis — title, meta description, canonical, H1/H2/H3 list, noindex / nofollow, lang.
• Social tags — Open Graph and Twitter Card, social-profile links, pixel detection (Facebook, Twitter, LinkedIn, Google Analytics).
• Technical SEO — charset, gzip/br compression, browser caching, HTTPS, schema.org markup, viewport, favicon.
• Content metrics — word and paragraph count, Flesch readability, keyword density, thin-content flag.
• Accessibility subset — aria-label / aria-describedby counts, skip-to-content link, heading structure, inputs missing a label.
• Carbon estimate — CO₂e per page view with an A–F rating.
• Spam / hidden-CSS / JavaScript analysis — common hack injection patterns, hidden elements, eval / document.write / base64 obfuscation and more.
• Cloaking detection — compares what the bot sees versus what Chrome sees (title, status code, content-size difference).
• VirusTotal link for the fetched domain.

REST API

Every fetch is also available as an authenticated JSON API (POST /umbraco/management/api/v1/utpro/url-viewer/fetch) — useful for CI pipelines or external tooling. The response includes the full analysis.audit object and the seoScore.

Architecture

This package is built on the framework-agnostic T4VN.Seo.Core engine, which provides the fetch pipeline, all analysis and SeoScorer — the single source of truth for the SEO score. Both this package and the companion site crawler (uTPro.Feature.SEOAudit) share the same engine, so scores are identical everywhere.

T4VN.Seo.Core  (engine, no Umbraco)
      ▲                  ▲
      │                  │
uTPro.Feature.UrlViewer  uTPro.Feature.SEOAudit
(this package)           (site-wide crawler — optional companion)

Security

All API endpoints are backoffice-secured under /umbraco/management/api/v1/utpro/... and require Settings-section access. Server-side fetches run behind an SSRF guard that blocks private/local addresses (RFC-1918, localhost, .local, CGNAT, link-local, IPv6 ULA/loopback) and re-checks on every redirect hop.

Installation

dotnet add package uTPro.Feature.UrlViewer

Configuration

No configuration is required for the URL Viewer tool itself. If you need to fetch internal/dev hosts:

{
  "uTPro": {
    "Feature": {
      "UrlViewer": {
        "AllowInternalHosts": false,
        "AllowInvalidCertificates": false
      }
    }
  }
}

Key	Default	Description
AllowInternalHosts	false	Relax the SSRF guard to allow fetching private/local addresses. Only for internal dev sites.
AllowInvalidCertificates	false	Accept self-signed / invalid TLS certificates. Only for internal dev sites.

License

Free to use (including commercially) under a proprietary End User License Agreement. Distributed as a compiled NuGet package — source is not published; modification, reverse-engineering and redistribution are not permitted.