yoga-redis

Type-safe PureScript FFI bindings for Redis using ioredis.

Overview

This package provides comprehensive bindings to Redis operations including:

• String operations (get, set, setex, etc.)
• Hash operations (hget, hset, hgetall, etc.)
• List operations (lpush, rpush, lpop, rpop, lrange, etc.)
• Set operations (sadd, srem, smembers, etc.)
• Sorted set operations (zadd, zrem, zrange, etc.)
• Pub/Sub support
• Connection management
• TTL and expiry operations

Installation

spago install yoga-redis

Make sure to also install the ioredis npm package:

npm install ioredis

Usage

Basic Operations

import Yoga.Redis as Redis
import Effect.Aff (launchAff_)

main = launchAff_ do
  -- Create and connect
  client <- Redis.createClient { url: "redis://localhost:6379" }
  Redis.connect client
  
  -- String operations
  Redis.set client (Redis.RedisKey "mykey") "myvalue"
  value <- Redis.get client (Redis.RedisKey "mykey")
  
  -- With expiry
  Redis.setex client (Redis.RedisKey "tempkey") (Redis.RedisTTL 60) "tempvalue"
  
  -- Hash operations
  Redis.hset client (Redis.RedisKey "user:1") "name" "John"
  Redis.hset client (Redis.RedisKey "user:1") "email" "john@example.com"
  user <- Redis.hgetall client (Redis.RedisKey "user:1")
  
  -- List operations
  Redis.lpush client (Redis.RedisKey "mylist") ["item1", "item2"]
  items <- Redis.lrange client (Redis.RedisKey "mylist") 0 (-1)
  
  -- Cleanup
  Redis.disconnect client

Configuration

import Yoga.Redis as Redis

config :: Redis.RedisConfig
config = 
  { host: Redis.RedisHost "localhost"
  , port: Redis.RedisPort 6379
  , password: Just (Redis.RedisPassword "mypassword")
  , db: Just (Redis.RedisDatabase 0)
  , keyPrefix: Just (Redis.RedisKeyPrefix "myapp:")
  , connectTimeout: Just (Redis.ConnectTimeout (Milliseconds 10000.0))
  }

main = launchAff_ do
  client <- Redis.createClientWithConfig config
  -- ... use client

Pub/Sub

import Yoga.Redis.PubSub as RedisPubSub

main = launchAff_ do
  -- Create separate clients for pub and sub
  pubClient <- Redis.createClient { url: "redis://localhost:6379" }
  subClient <- Redis.createClient { url: "redis://localhost:6379" }
  
  -- Subscribe to channel
  RedisPubSub.subscribe subClient "notifications" \message -> do
    log $ "Received: " <> message
  
  -- Publish message
  RedisPubSub.publish pubClient "notifications" "Hello, World!"

Type Safety

All Redis keys are wrapped in a RedisKey newtype for type safety:

newtype RedisKey = RedisKey String

Similarly, TTL values, passwords, and other configuration values use newtypes:

newtype RedisTTL = RedisTTL Int
newtype RedisPassword = RedisPassword String
newtype RedisHost = RedisHost String
newtype RedisPort = RedisPort Int

API Reference

Connection Management

• createClient - Create Redis client from URL
• createClientWithConfig - Create client with detailed configuration
• connect - Connect to Redis
• disconnect - Disconnect from Redis
• quit - Gracefully quit connection
• ping - Test connection

String Operations

• get - Get value by key
• set - Set key to value
• setex - Set key with expiry time
• del - Delete key(s)
• exists - Check if key exists
• incr / incrBy - Increment value
• decr / decrBy - Decrement value

Hash Operations

• hget - Get field from hash
• hset - Set field in hash
• hgetall - Get all fields from hash
• hdel - Delete field from hash
• hexists - Check if field exists
• hkeys - Get all field names
• hlen - Get number of fields

List Operations

• lpush / rpush - Push to list
• lpop / rpop - Pop from list
• lrange - Get range of elements
• llen - Get list length

Set Operations

• sadd - Add members to set
• srem - Remove members from set
• smembers - Get all members
• sismember - Check membership
• scard - Get set size

Sorted Set Operations

• zadd - Add members with scores
• zrem - Remove members
• zrange - Get range by index
• zcard - Get sorted set size
• zscore - Get member score

TTL Operations

• expire - Set key expiry
• ttl - Get time to live

Integration with Om

For Om-based applications, see yoga-redis-om which provides Om-wrapped operations and layer management.

Related Packages

• yoga-redis-om - Om-wrapped Redis operations
• ioredis - The underlying Node.js Redis client

License

MIT