Cache Services Overview

DreamFactory supports multiple caching backends to improve API performance. Caching stores frequently accessed data in memory, reducing database load and improving response times for read-heavy workloads.

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Supported Cache Services

Service	Type	Use Case	Documentation
Redis	In-memory store	Production caching, sessions, queues	Redis Guide
Memcached	In-memory cache	Simple key-value caching	Memcached Guide
Local	File-based	Development, single-instance deployments	Built-in
File	File-based	Development, disk-based persistence	Built-in
Database	SQL-backed	Simple deployments without external cache	Built-in

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Cache Use Cases in DreamFactory

API Response Caching

Cache API responses to reduce database queries:

• Per-service caching: Enable caching on individual database or file services
• TTL configuration: Set expiration times based on data volatility
• Cache invalidation: Automatic clearing on write operations

Session Storage

Store user sessions in a distributed cache:

• Scalability: Share sessions across multiple DreamFactory instances
• Performance: Faster session lookups than database
• Persistence: Redis can persist sessions across restarts

Rate Limiting

Track API request counts per user or role:

• Distributed counting: Works across load-balanced instances
• Atomic operations: Accurate request tracking
• Automatic expiry: Counters reset after time windows

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Choosing a Cache Backend

Redis vs Memcached

Feature	Redis	Memcached
Data structures	Strings, lists, sets, hashes, sorted sets	Strings only
Persistence	Optional disk persistence	Memory only
Replication	Master-slave, clustering	None (client-side)
Pub/Sub	Yes	No
Lua scripting	Yes	No
Memory efficiency	Good	Excellent for simple data
Max key size	512 MB	1 MB
Use case	Feature-rich, sessions, queues	Simple caching

Recommendation

• Production: Use Redis for its flexibility, persistence options, and support for sessions
• Development: Use Local cache for simplicity
• High-volume simple caching: Use Memcached for maximum memory efficiency

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Cache Architecture

┌─────────────────┐     ┌──────────────────┐     ┌─────────────────┐
│   API Client    │────▶│   DreamFactory   │────▶│    Database     │
│                 │◀────│                  │◀────│                 │
└─────────────────┘     └────────┬─────────┘     └─────────────────┘
                                 │
                                 │ Cache check
                                 ▼
                        ┌─────────────────┐
                        │  Cache Backend  │
                        │  (Redis/Memcached)
                        └─────────────────┘

Cache Flow

1. Request arrives at DreamFactory
2. Cache check: If cached response exists and is valid, return it
3. Cache miss: Query the database/service
4. Store in cache: Save response with configured TTL
5. Return response to client

Cache Invalidation

DreamFactory automatically invalidates cache entries when:

• POST/PUT/PATCH/DELETE operations modify data
• TTL expires based on configured duration
• Manual flush via admin API

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Configuring Cache Services

System-Wide Cache

Configure the default cache backend in DreamFactory's environment:

CACHE_DRIVER=redis
REDIS_HOST=localhost
REDIS_PORT=6379
REDIS_PASSWORD=your_password

Per-Service Caching

Enable caching on individual services:

1. Navigate to the service configuration
2. Enable Cache Enabled option
3. Set Cache TTL in seconds
4. Save the service

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Cache API Endpoints

DreamFactory exposes a Cache API for direct cache operations:

Method	Endpoint	Description
GET	/api/v2/{cache_service}/{key}	Get cached value
POST	/api/v2/{cache_service}	Store value in cache
DELETE	/api/v2/{cache_service}/{key}	Delete cached value
DELETE	/api/v2/{cache_service}	Flush all cached values

Example: Store a Value

curl -X POST "https://example.com/api/v2/cache" \
  -H "X-DreamFactory-API-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "key": "user:123:profile",
    "value": {"name": "John", "email": "john@example.com"},
    "ttl": 3600
  }'

Example: Retrieve a Value

curl -X GET "https://example.com/api/v2/cache/user:123:profile" \
  -H "X-DreamFactory-API-Key: YOUR_API_KEY"

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Performance Best Practices

TTL Configuration

Data Type	Recommended TTL	Rationale
Static reference data	24 hours	Rarely changes
User profiles	5-15 minutes	Balances freshness and performance
Real-time data	30-60 seconds	Frequently updated
Session data	30 minutes - 2 hours	Matches session duration

Cache Key Design

Use structured, predictable key patterns:

{resource_type}:{id}:{sub_resource}

Examples:

• user:123:profile
• product:456:inventory
• order:789:items

Memory Management

• Monitor memory usage to prevent eviction
• Set appropriate TTLs to expire stale data
• Use Redis maxmemory-policy for graceful eviction

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Common Errors

Error Code	Message	Cause	Solution
400	Bad Request	Invalid key or value format	Check request payload
401	Unauthorized	Missing API key	Add API key header
404	Not Found	Key does not exist	Handle cache miss in client
503	Service Unavailable	Cache backend unreachable	Check cache server status

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Next Steps

• Redis: Configure Redis for production caching
• Memcached: Configure Memcached for simple caching
• Performance Tuning: Optimize DreamFactory performance