BeginTransaction is not async results in connection to be opened async

[ramonsmits]

BeginTransaction is not async results in connection to be opened async. I'm not entirely sure but I assume BeginTransaction will result in a transaction to be started if not already running thus a connection to be opened. I'm getting FirstChangeExceptions on my NpgSql setup

System.Net.Internals.SocketExceptionFactory+ExtendedSocketException (10035): A non-blocking socket operation could not be completed immediately. 192.168.149.149:5433

In https://github.com/npgsql/npgsql/issues/1183 it is mentioned this is because the connection is opened via .Open instead of .OpenAsync. I looked in the code and DriverConnectionProvider supports async but it seems it isn't used. Further analys shows that DriverBase doesn't have an async BeginTransaction.

I think an async BeginTransaction makes sense but maybe there is a workaround?

[bahusoid]

but maybe there is a workaround

You can try to force session to open async connection before calling session.BeginTransaction. Something like:

await (session.GetSessionImplementation().ConnectionManager.GetConnectionAsync(cancelationToken)).ConfigureAwait(false);

[ramonsmits]

@bahusoid thanks for that tip, I've created the following extension method around it which I'll test later.

static class SessionExt
{
    public async static Task<ITransaction> BeginTransactionAsync(
        this ISession session,
        IsolationLevel isolationLevel = IsolationLevel.Unspecified,
        CancellationToken cancellationToken = default
        )
    {
        await session
            .GetSessionImplementation()
            .ConnectionManager
            .GetConnectionAsync(cancellationToken)
            .ConfigureAwait(false);

        return session.BeginTransaction(isolationLevel);
    }
}