public static void UseMessageQueue(this Configuration config, string tablename = "messages")
{
config.GetOrAddTable(new QueueTable(tablename));
config.Decorate <Func <DocumentTransaction, DmlCommand, Func <object> > >((_, decoratee) => (tx, command) => () =>
Switch <object> .On(command)
.Match <EnqueueCommand>(enqueueCommand => EnqueueCommand.Execute(config.Serializer.Serialize, tx, enqueueCommand))
.Match <DequeueCommand>(dequeueCommand => DequeueCommand.Execute(config.Serializer.Deserialize, tx, dequeueCommand))
.Else(() => decoratee(tx, command)()));
}
public static string Execute(Func <object, string> serializer, DocumentTransaction tx, EnqueueCommand command)
{
var tablename = tx.Store.Database.FormatTableNameAndEscape(command.Table.Name);
var discriminator = tx.Store.Configuration.TypeMapper.ToDiscriminator(command.Message.GetType());
try
{
tx.SqlConnection.Execute(@$ "
set nocount on;
insert into {tablename} (Topic, Id, CommitId, Discriminator, Message)
values (@Topic, @Id, @CommitId, @Discriminator, @Message);
set nocount off;",
new
{
command.Topic,
command.Message.Id,
tx.CommitId,
Discriminator = discriminator,
Message = serializer(command.Message)
},
tx.SqlTransaction);
}
catch (SqlException e)
{
// Enqueuing is idempotent. It should ignore exceptions from primary key violations and just not insert the message.
if (e.Number == 2627)
{
return(command.Message.Id);
}
throw;
}
return(command.Message.Id);
}