gofr-dev/gofr

# Connecting to Redis

GoFr simplifies the process of connecting to Redis.

## Setup:

Ensure you have Redis installed on your system.

Optionally, you can use Docker to set up a development environment as described below.

```bash
docker run --name gofr-redis -p 6379:6379 -d redis
```

You can also set up a development environment with password authentication as described below.

```bash
docker run --name gofr-redis -p 2002:6379 -d \
  -e REDIS_PASSWORD=password \
  redis:7.0.5 --requirepass password
```

You can set a sample key `greeting` using the following command:

```bash
docker exec -it gofr-redis bash -c 'redis-cli SET greeting "Hello from Redis."'
```

## Configuration & Usage

GoFr applications relies on environment variables to configure and connect to a Redis server. 
These variables are stored in a file named `.env` located within the configs directory in your project root.

Following configuration keys are required for Redis connectivity:

* `REDIS_HOST`: It specifies the hostname or IP address of your Redis server.
* `REDIS_PORT`: It specifies the port number on which your Redis server is listening. The default Redis port is 6379.
* `REDIS_USER` : This is the user you'll use to connect to your Redis server. You can configure multiple users with different permissions in a single Redis container. For more details, refer to the [official docs](https://redis.io/docs/latest/operate/oss_and_stack/management/security/acl/)
* `REDIS_PASSWORD`: The password is required only if your Redis server is configured for authentication; if authentication is not enabled, no password is necessary.
* `REDIS_DB`: The database number to use for the Redis server. The default value is 0.
```dotenv
APP_NAME=test-service
HTTP_PORT=9000

REDIS_HOST=localhost
REDIS_PORT=6379
REDIS_PASSWORD=password
REDIS_DB=2
```

The following code snippet demonstrates how to retrieve data from a Redis key named "greeting":

```go
package main

import (
    "errors"

    "github.com/redis/go-redis/v9"

    "gofr.dev/pkg/gofr"
)

func main() {
    // Initialize GoFr object
    app := gofr.New()

    app.GET("/redis", func(ctx *gofr.Context) (interface{}, error) {
        // Get the value using the Redis instance

        val, err := ctx.Redis.Get(ctx.Context, "greeting").Result()
        if err != nil && !errors.Is(err, redis.Nil) {
            // If the key is not found, we are not considering this an error and returning ""
            return nil, err
        }

        return val, nil
    })

    // Run the application

    app.Run()
}
```