Help4 Net
Joomla extension tutorial

Clear only the Joomla content that changed

Help4 CDN can clear selected local paths or the registered domain. The content plugin handles routine publishing while browser-cache policy stays separate from private Joomla sessions.

Choose the narrowest clear

ChangeActionReason
One article, image, CSS, or scriptClear selected pathsEvicts only the affected public objects.
Several known routesEnter one local path per linePaths are normalized and foreign-host URLs fail closed.
Template, menu, module, or global layoutClear domainUse when the public change reaches many routes.
Routine content save/delete/state changeAutomatic invalidationThe enabled content plugin requests a site-scoped clear after Joomla completes the change.

Clear selected paths

  1. Open Components, Help4 CDN.
    Confirm the dashboard shows a Help4 site ID.
  2. Enter local paths.
    Use one path per line, such as /news/launch or /images/site/hero.webp. Same-host absolute URLs are normalized.
  3. Select Clear selected paths.
    The request includes the registered site identity and Joomla origin context.
  4. Check the last-purge status.
    An accepted request records its time and status. An error remains visible without changing unrelated cache.
  5. Verify body and headers.
    Confirm a known content marker or checksum and the expected Help4 POP; HTTP 200 by itself is not sufficient.
Use Clear domain deliberately. A domain clear is appropriate after a global template or navigation change, not after every article edit.

Automatic invalidation

When Content - Help4 CDN automatic invalidation is enabled and automatic cache management is selected, Joomla content save, delete, and state-change events request a public domain invalidation at most once per request.

Fail-open publishing

A Help4 API error does not block the Joomla content save. The site remains editable while the stale-object condition is reported for follow-up.

Private-route safety

The invalidation request does not authorize public caching of administrator, login, cookie-bearing, personalized, or non-200 responses.

Browser cache policy

Respect origin

Use Joomla or the origin's deliberate Cache-Control policy when it already separates mutable HTML from versioned static files.

Custom policy

Set a bounded max age for public assets. Select immutable only when the filename changes with the file contents.

Never use immutable for unversioned files or personalized HTML. Authentication, administrator, account, session, and cookie-bearing responses must remain BYPASS/no-store at the edge.

Freshness verification

  1. Load the updated route without a Joomla administrator cookie.
  2. Confirm the expected text, asset version, or SHA-256 body hash.
  3. Inspect X-Help4-Pop, cache state, proxy mode, WAF mode, and content type.
  4. Test administrator and login routes separately and confirm they remain private.
curl -sSI https://example.com/news/launch
curl -sS https://example.com/news/launch | openssl dgst -sha256
Next: configure WAF, managed bot challenge, headers, and access policy in the Joomla security tutorial.