Wait for Power BI to Get Going

[saviourofdp]

currently I think the PBI support checks for the existence of the msmdsrv process before throwing if it can't find it.

https://github.com/Seddryck/NBi/blob/620544d23c0f52eb606c0c6dfcd67548fce538df/NBi.Core/PowerBiDesktop/PowerBiDesktopConnectionStringBuilder.cs

protected virtual string BuildLocalConnectionString(string name)
  {
      var processes = System.Diagnostics.Process.GetProcessesByName("msmdsrv");
      if (processes==null || processes.Count()==0)
      {
          throw new ConnectionException
                  (
                      new InvalidOperationException("No process found with the name 'msmdsrv'. Are you sure your Power BI desktop solution is running?")
                      , string.Format("PBIX = {0}", name)
                  );
      }

 // ...
 }

If NBi is configured to start the PBIDesktop.exe in <setup />, the current version takes a while to get going which means this is very likely to fail. Would it be possible to poll until the process is up, only failing after a timeout? Something like this perhaps:

private static async Task DelayUntilServerIsRunningAsync(int delay = 2000, int timeout = 10000)
{
   var end = DateTime.Now.AddMilliseconds(timeout);
    var processes = System.Diagnostics.Process.GetProcessesByName("msmdsrv");
    while (!processes.Any() && DateTime.Now < end)
    {
        await Task.Delay(delay);
        processes = System.Diagnostics.Process.GetProcessesByName("msmdsrv");
    }
    if(!processes.Any()) {
         throw new ConnectionException
                  (
                      new InvalidOperationException("No process found with the name 'msmdsrv'. Are you sure your Power BI desktop solution is running?")
                 );
    }
}

Also I have noticed that Power BI accepts a /diagnosticsPort command line parameter which allows you to specify the port of the AS server.

[Seddryck]

Thanks for the feedback and the contribution. Sounds great, will add that to the next release.

[Seddryck]

Code added and bug fix available in 1.23.0-beta0167