Performing one time migrations with RavenDB

gistfile1.cs

    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Starting migration.");

            using (var store = new DocumentStore { ConnectionStringName = "RavenDb" }.Initialize()) 
            {
                using (var session = store.OpenSession())
                {
                    var applications = session
					.Query<VacancyApplication>()
					.Include(a => a.VacancyId)
					.As<RavenJObject>();

                    foreach (var application in applications)
                    {
                        var vacancy = session.Load<Vacancy>(application["VacancyId"].Value<string>());
                        if (vacancy == null)
                            throw new Exception();

                        // copy client id from vacancy
                        if (!application.ContainsKey("ClientId"))
                        {
                            application["ClientId"] = vacancy.ClientId;
                        }

                        // set reason for approving
                        if (!application.ContainsKey("ReasonForApproving"))
                        {
                            application["ReasonForApproving"] = application["ReasonForShortlisting"];

                            // transition anything that is shortlisted to approved
                            if (application["StateId"].Value<string>() == "Shortlisted")
                            {
                                application["StateId"] = "Approved";
                            }
                        }
                    }

                    session.SaveChanges();
                }
            }

            Console.WriteLine("Migration complete.");
            Console.ReadLine();
        }
    }