# Go Redis Inventory

A Go library for managing inventory using Redis.

## Features

- Get and update inventory quantities
- Reserve inventory with atomic operations using Lua scripts
- Temporary cart-based reservations with expiration to prevent overselling
- Optimized available inventory calculation using maintained reservation totals
- Listen to inventory changes via Redis pub/sub

## Installation

```bash
go get github.com/matst80/go-redis-inventory
```

## Usage

Import the package:

```go
import "git.k6n.net/go-redis-inventory/pkg/inventory"
```

Create a Redis client and initialize the service:

```go
client := redis.NewClient(&redis.Options{
    Addr: "localhost:6379",
})
service, err := inventory.NewRedisInventoryService(client)
if err != nil {
    log.Fatal(err)
}
```

For cart reservations:

```go
cartService, err := inventory.NewRedisCartReservationService(client)
if err != nil {
    log.Fatal(err)
}

// Reserve items for a cart with 10-minute TTL
err = cartService.ReserveForCart(ctx, inventory.CartReserveRequest{
    InventoryReference: &inventory.InventoryReference{SKU: "item1", LocationID: "warehouse1"},
    CartID: "cart123",
    Quantity: 2,
    TTL: 10 * time.Minute,
})

// Get available inventory (accounting for reservations)
available, err := cartService.GetAvailableInventory(ctx, "item1", "warehouse1")

// Get reservation summary for an item
summary, err := cartService.GetReservationSummary(ctx, "item1", "warehouse1")
fmt.Printf("Reservations: %d, Next release: %v, Remaining: %d\n", summary.ReservationCount, summary.EarliestRelease, summary.RemainingItems)
```

## Dependencies

- Go 1.25.1 or later
- Redis server
- [github.com/redis/go-redis/v9](https://github.com/redis/go-redis)