github.com/alexedwards/scs/redisstore

redisstore

A Redis based session store for SCS.

Setup

You should follow the instructions to setup a connection pool, and pass the pool to redisstore.New() to establish the session store.

Example

package main

import (
	"io"
	"net/http"

	"github.com/alexedwards/scs/v2"
	"github.com/alexedwards/scs/redisstore"
	"github.com/gomodule/redigo/redis"
)

var sessionManager *scs.SessionManager

func main() {
	// Establish connection pool to Redis.
	pool := &redis.Pool{
		MaxIdle: 10,
		Dial: func() (redis.Conn, error) {
			return redis.Dial("tcp", "host:6379")
		},
	}
	
	// Initialize a new session manager and configure it to use redisstore as the session store.
	sessionManager = scs.New()
	sessionManager.Store = redisstore.New(pool)

	mux := http.NewServeMux()
	mux.HandleFunc("/put", putHandler)
	mux.HandleFunc("/get", getHandler)

	http.ListenAndServe(":4000", sessionManager.LoadAndSave(mux))
}

func putHandler(w http.ResponseWriter, r *http.Request) {
	sessionManager.Put(r.Context(), "message", "Hello from a session!")
}

func getHandler(w http.ResponseWriter, r *http.Request) {
	msg := sessionManager.GetString(r.Context(), "message")
	io.WriteString(w, msg)
}

Expired Session Cleanup

Redis will automatically remove expired session keys.

Key Collisions

By default keys are in the form scs:session:<token>. For example:

"scs:session:ZnirGwi2FiLwXeVlP5nD77IpfJZMVr6un9oZu2qtJrg"

Because the token is highly unique, key collisions are not a concern. But if you're configuring multiple session managers, both of which use redisstore, then you may want the keys to have a different prefix depending on which session manager wrote them. You can do this by using the NewWithPrefix() method like so:

pool := &redis.Pool{
    MaxIdle: 10,
    Dial: func() (redis.Conn, error) {
        return redis.Dial("tcp", "host:6379")
    },
}

sessionManagerOne = scs.New()
sessionManagerOne.Store = redisstore.NewWithPrefix(pool, "scs:session:1:")

sessionManagerTwo = scs.New()
sessionManagerTwo.Store = redisstore.NewWithPrefix(pool, "scs:session:2:")

Iterating over all Sessions

If you intend to use the sessionstore.Iterate() function to iterate over all sessions on a busy Redis server with many keys stored, be warned that this can take a long time and is therefore probably only interesting for debugging purposes.