permissions.go

package config

import (
    "time"
)

// Here we declare an interface representing our local
// needs from the configuration db, namely,
// the `AllPermissions` method.
type PermissionDB interface {
    AllPermissions() map[string][]string // maps from role to its permissions
}

// Then we export a service than will provide the
// permissions from memory, to use it, another package
// will have to declare a local interface.
type PermissionStorage struct {
    permissions map[string][]string
}

func NewPermissionStorage(db PermissionDB) *PermissionStorage {
    s := &PermissionStorage{}
    s.permissions = db.AllPermissions()
    go func() {
        for {
            time.Sleep(time.Hour)
            s.permissions = db.AllPermissions()
        }
    }()
    return s
}

func (s *PermissionStorage) RolePermissions(role string) []string {
    return s.permissions[role]
}