Redis Caching¶

R Commerce uses Redis for high-performance caching and session storage. This guide covers configuration, monitoring, and best practices.

Overview¶

Redis is used for:

Product Catalog Caching - Fast product lookups
Session Storage - Shopping cart and user sessions
Rate Limiting - API throttling
Token Blacklist - JWT revocation
WebSocket Sessions - Real-time connection state

Configuration¶

Basic Configuration¶

[cache]
cache_type = "Redis"
redis_url = "redis://localhost:6379/0"
redis_pool_size = 20

Production Configuration¶

[cache]
cache_type = "Redis"
redis_url = "redis://redis-cluster:6379/0"
redis_pool_size = 50

Environment Variable¶

You can also set Redis URL via environment:

export REDIS_URL=redis://localhost:6379/0

Running Redis¶

Docker¶

docker run -d \
  --name rcommerce-redis \
  -p 6379:6379 \
  redis:7-alpine

Docker Compose¶

version: '3.8'
services:
  redis:
    image: redis:7-alpine
    ports:
      - "6379:6379"
    volumes:
      - redis_data:/data
    command: redis-server --appendonly yes

volumes:
  redis_data:

Homebrew (macOS)¶

brew install redis
brew services start redis

Cache Namespaces¶

R Commerce uses key prefixes to avoid collisions:

Namespace	Purpose	Example Key
`product`	Product catalog cache	`product:123e4567`
`session`	User sessions	`session:abc123`
`cart`	Shopping carts	`cart:user:123`
`rate:limit`	Rate limiting	`rate:limit:ip:192.168.1.1`
`token:blacklist`	Revoked tokens	`token:blacklist:xyz789`

Monitoring¶

Redis CLI¶

# Connect to Redis
redis-cli

# Check connected clients
INFO clients

# Memory usage
INFO memory

# Key statistics
DBSIZE

# Slow queries
SLOWLOG GET 10

Health Check¶

The server logs Redis connection status on startup:

INFO Connecting to Redis at redis://localhost:6379/0...
INFO Redis connected successfully

If Redis is unavailable, the server continues without caching:

WARN Failed to connect to Redis: Connection refused. Continuing without cache.

Performance Tuning¶

Connection Pool Size¶

Recommended pool sizes:

Environment	Pool Size	Notes
Development	5	Minimal connections
Production	20-50	Based on load
High Traffic	100+	With Redis Cluster

TTL Configuration¶

Default TTL values:

Products: 1 hour
Sessions: 2 hours
Rate Limits: 1 hour
API Cache: 5 minutes

High Availability¶

Redis Sentinel¶

For automatic failover:

[cache]
redis_url = "redis://sentinel:26379"
sentinel_enabled = true
sentinel_nodes = ["sentinel1:26379", "sentinel2:26379"]
sentinel_service = "mymaster"

Redis Cluster¶

For horizontal scaling:

[cache]
redis_url = "redis://node1:6379"
cluster_enabled = true
cluster_nodes = [
    "node1:6379",
    "node2:6379",
    "node3:6379"
]

Troubleshooting¶

Connection Errors¶

ERROR: Redis connection error: Connection refused

Solution: Check Redis is running and URL is correct.

Memory Issues¶

WARNING: Redis memory usage high

Solution: - Enable key expiration (TTL) - Set maxmemory-policy allkeys-lru - Increase Redis server memory

Slow Queries¶

# Find slow commands
redis-cli SLOWLOG GET 10

Security¶

Enable Authentication¶

[cache]
redis_url = "redis://:password@localhost:6379/0"

TLS/SSL¶

[cache]
redis_url = "rediss://localhost:6380/0"
use_tls = true
verify_certificate = true

Network Security¶

Use firewall rules to restrict Redis access
Bind Redis to localhost or private network
Never expose Redis to the public internet