Caching

Caching can significantly improve performance when rendering the same content repeatedly. The bundle integrates with Symfony's cache component.

Enable Caching

# config/packages/symfony_djot.yaml
symfony_djot:
    cache:
        enabled: true
        pool: cache.app    # Uses Symfony's default cache pool

How It Works

1. Content is hashed using xxHash (fast, collision-resistant)
2. Rendered HTML is stored in the cache pool
3. Subsequent renders of identical content return cached HTML
4. Cache keys are prefixed with symfony_djot_html_

Cache Pools

Use any Symfony cache pool:

# config/packages/cache.yaml
framework:
    cache:
        pools:
            cache.djot:
                adapter: cache.adapter.redis
                default_lifetime: 3600

# config/packages/symfony_djot.yaml
symfony_djot:
    cache:
        enabled: true
        pool: cache.djot

Common Pool Configurations

Redis (recommended for production):

framework:
    cache:
        pools:
            cache.djot:
                adapter: cache.adapter.redis
                provider: 'redis://localhost'

Filesystem (development):

framework:
    cache:
        pools:
            cache.djot:
                adapter: cache.adapter.filesystem
                directory: '%kernel.cache_dir%/djot'

APCu (single server):

framework:
    cache:
        pools:
            cache.djot:
                adapter: cache.adapter.apcu

Cache Invalidation

The cache is keyed by content hash, so:

• Changed content automatically gets a new cache entry
• Old entries expire based on the pool's TTL
• Manual clearing via Symfony's cache:clear command

# Clear all caches
php bin/console cache:pool:clear cache.djot

# Or clear everything
php bin/console cache:clear

When to Use Caching

Good candidates:

• Static content (about pages, documentation)
• Blog posts that don't change often
• Repeated rendering of the same content

Skip caching for:

• User-specific content with variables
• Rapidly changing content
• Very short content (overhead > benefit)

Performance Considerations

Scenario	Recommendation
Blog with 100 posts	Enable caching with Redis
User comments	Usually skip (too many unique entries)
Documentation site	Enable with filesystem cache
Real-time editor preview	Disable caching

Measuring Impact

Enable Symfony's profiler to see cache hit/miss rates:

# config/packages/dev/cache.yaml
framework:
    cache:
        pools:
            cache.djot:
                adapter: cache.adapter.filesystem
                tags: true  # Enables tagging/tracking

Check the profiler's Cache panel to see symfony_djot_html_* entries.

Next Steps

• Configuration — full configuration reference
• Service Usage — using the converter in code