Best practice to maintain a mgo session

Question

I\'m currently using a mongodb with mgo lib for a web application, but I\'m not sure if the way I\'m using it, is good one ..

package db

import (
    \"gopk         


        

Answer 1

With go 1.7, the most idiomatic way of handling mongo session on a webserver is to use the new standard library package context to write a middleware that can attach the defer session.Close() to whenever the request context Done() is called. So you do not need to remeber to close

AttachDeviceCollection = func(next http.Handler) http.Handler {
        return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
            db, err := infra.Cloner()
            if err != nil {
                http.Error(w, err.Error(), http.StatusInternalServerError)
                return
            }
            collection, err := NewDeviceCollection(db)

            if err != nil {
                db.Session.Close()
                http.Error(w, err.Error(), http.StatusInternalServerError)
                return
            }
            ctx := context.WithValue(r.Context(), DeviceRepoKey, collection)
            go func() {
                select {
                case <-ctx.Done():
                    collection.Session.Close()
                }
            }()

            next.ServeHTTP(w, r.WithContext(ctx))
        })
    }