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Introduction

The Problem: 20 Years of Temporal Cache Issues

TYPO3 Forge Issue #14277 was reported in August 2004 and remains unsolved as of 2025.

Root Cause

TYPO3's cache invalidation architecture is event-driven (invalidates when data changes) but doesn't handle temporal dependencies (when time passes).

The cache system supports:

  • ✅ Event-driven invalidation: Invalidate when page edited/deleted
  • ✅ Tag-based invalidation: Flush specific cache entries by tag
  • ✅ Relative TTL: Cache for N seconds from NOW

But it's missing:

  • ❌ Temporal invalidation: Invalidate at absolute timestamp
  • ❌ Time-aware caching: Understand time-based visibility rules

Symptoms

When pages or content elements have starttime or endtime values set:

Expiring Content:
Pages with endtime remain visible in menus after expiration until cache is manually cleared.
Scheduled Content:
Pages with starttime don't appear in menus when their scheduled time arrives until cache is manually cleared.
Content Elements:
Content blocks with starttime/endtime don't update automatically in cached page output.
Other Components:
Sitemaps, search results, breadcrumbs, and any cached listings don't reflect time-based visibility changes.

Impact

This affects ALL TYPO3 installations using:

  • Navigation menus (HMENU)
  • Scheduled content publication
  • Content elements with time restrictions
  • News/blog posts with publication dates
  • Event calendars
  • Any extension using starttime/endtime fields

Severity: HIGH

  • Core CMS functionality (content scheduling) is unreliable
  • No automatic solution exists in TYPO3 core
  • Manual cache clearing required for every time-based transition
  • Affects production sites' editorial workflows

Community Impact

  • Age: 20+ years unresolved (2004-2025)
  • Watchers: 5+ users actively tracking
  • Versions: Confirmed affecting v9.5.7 through v14
  • Scope: System-wide architectural limitation

Related Issues

  • #16815 - Sitemap ignoring start/end flags
  • #98964 - Menu caching excessive cache_hash records

Why It Took 20 Years to Solve

The issue manifests differently across components:

Menus:
"Page is live but not in navigation"
Content Elements:
"I had to clear cache to make scheduled content appear"
Search:
"Search results show expired pages"

Same root cause, different symptoms - making systematic diagnosis difficult.

What This Extension Does

Important

Extension Status: This extension is stable and production-ready. The code is thoroughly tested, follows TYPO3 best practices, and is professionally maintained.

Approach Status: The temporal cache solution is experimental. This extension implements Phase 1 as a pragmatic workaround with known limitations (site-wide cache synchronization) until TYPO3 core provides native temporal cache support (Phase 2/3).

Implements Phase 1 of a three-phase solution:

  1. Phase 1 (This Extension): Dynamic cache lifetime based on next temporal transition - works TODAY with current TYPO3 versions
  2. Phase 2 (Future Core): Absolute expiration API in TYPO3 cache system (planned for v15/v16)
  3. Phase 3 (Future Core): Automatic temporal cache awareness (long-term vision)

See :ref:`phases` for complete roadmap, migration path, and detailed explanation of why Phase 1 is necessary today.

Quick Start

Installation:

composer req netresearch/typo3-temporal-cache

Configuration:

None required! Extension works automatically after installation.

Result:

✅ Menus update when pages reach starttime/endtime ✅ Content elements appear/disappear automatically ✅ Sitemaps and listings stay current ✅ Zero manual cache clearing needed

Next Steps