purescript-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