Feature Request: enumerate all sessions

[Delphier]

In our application, want to implement a feature that is to view all online users and terminate a user session. I tried to get all the sessions to complete this feature, but did not find any method.

If using dbStore, I can get it directly from the database, but we use a memstore. I tried to read * MemStore directly, but his items field is private.

Hope to add a interface that can enumerate all sessions, which is very useful.

[alexedwards]

I can see that this would be useful, but would require changing the Store interface, which would be a breaking change for anyone using their own custom Store.

In the past, my response for this kind of request has always been to access the database directly like you suggest. But you're quite right... that doesn't work for MemStore.

We could potentially add a MemStore.Tokens() method which returns a slice of all non-expired tokens? You could then iterate through that, calling the MemStore.Find() method to fetch the user details and MemStore.Delete() method to remove a specific session.

Would that work?

[Delphier]

Thanks for your response, I think it works, and the changes are minimal.

[alexedwards]

I've just added an Iterate() method to SCS in commit https://github.com/alexedwards/scs/commit/eb62bb0aaffff869692cdb516da5bee65d62e3a2. Essentially, you pass the Iterate() method a closure with the signature func(ctx context.Context) error which contains the logic that you want to execute against each session.

For example, if you want to revoke all sessions with contain a userID value equal to 4 you can do the following:

err := sessionManager.Iterate(func(ctx context.Context) error {
    userID := sessionManager.GetInt(ctx, "userID")

    if userID == 4 {
        return sessionManager.Destroy(ctx)
    }

    return nil
})

if err != nil {
    log.Fatal(err)
}

Session iteration is currently supported by memstore and postgresstore store implementations via an new IterableStore interface. The Iterate() method checks that the store supports iteration before doing anything (it panics if it is not supported). I felt that this approach was better than making a breaking change to the Store interface.

[alexedwards]

Thanks to @gandaldf the IterableStore interface is now also supported by:

• redisstore
• buntdbstore
• mysqlstore
• sqlite3store
• pgxstore

This leaves only the following stores which need to be updated still:

• badgerstore
• boltstore
• mockstore
• mongodbstore

[gandaldf]

I'm planning to complete the list asap! I will PR a mssql store too, so scs will support more or less the same RDBMS that most ORMs support.

[alexedwards]

@gandaldf That sounds great, thank you :pray:

[gandaldf]

Here we go: #121

[alexedwards]

@gandaldf Thanks so much for your time and effort on this :+1:

I've merged your PR just now.