[twsocket] SmtpClient and aborting connection
Hello, I finally got it working now by using (and somewhat enhancing) that thread approach. I've left out the cancelling on long lasting connection attempts right now, maybe I add it later and I think I might want to do it on shutdown as well. Greetings Markus -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
[twsocket] SmtpClient and aborting connection
Hello, I#ve a new idea and would like some expert opinions about it before wasting time on it: what if I put the e-mail sending in a seperate thread where the SmptCLient is bound to the thread (execute)? So it would have its own message loop which hopefully wouldn't interfere with the rest of the com-server. The only thing are the test and the other synchronously sending method which should return success or not and shutting down the com-server might be another problem. Btw. and off topic: why is there a initialization method in the automation server you can override but no finalization? So you never know within the com server when it's time to finish/clean up, right? Greetings Markus -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
[twsocket] SmtpClient and aborting connection
Hello, my COM server goes havoc when the e-mail has been sent. If the client calls some simple functions which normally would only read something from the database and return the value they fail instead. Functions which aren't really interdependant or so. I'm wondering now why. It also happens with my printing code as it seems. So my guess now is that it's related that both are (at least this is what I think) within the context of a TWSocket's OnDataAvailable. Could it be that the message handling for the e-mailing etc. can cause this? If yes, how to circumvent this? Greetings Markus -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
Re: [twsocket] SmtpClient and aborting connection
Hello Markus, You dont have to loop. Just set a Timer and Connect, that's all. You can disable the Timer in OnSessionConnected. If timer expires just call Abort. When OnSessionClosed is called set a flag. When OnRequestDone is called and session is closed start your next connection (depending on success or not what you can set in in one of the events). --- Rgds, Wilfried [TeamICS] http://www.overbyte.be/eng/overbyte/teamics.html http://www.mestdagh.biz -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
[twsocket] SmtpClient and aborting connection
Hello, I've still or even worse trouble with this e-mail sending. maybe I should explain it more in detail what my environment is and what I want to do. Okay I have this: COM Client - COM-Server - ICS SmtpClient | Other application connected via TWSocket (TCP) The com server provides 3 functions for sending e-mails, one is used internally triggered by certain events sent by the other application. The two methods for sending e-mails (one for a testmail for testing the connection) the other for sending something specific shall send the e-mail and return whether this was successfull or not. If the sending takes more that a certain time it shall be aborted and counted as unsuccessfull. Sending is done in a loop over a list possibly containing more that one e-mail server address to that if the first fails the second will be tried etc. After the connect I've this here: t:=GetTickCount; while ((isemail_connection = true) and (mailerror = 0)) and (((GettickCount = t) and (GetTickCount-t timeout)) xor ((GettickCount t) and (t-GetTickCount timeout))) do begin sleep(10); Application.ProcessMessages; end; if (mailerror 0) or (isemail_connection = true) then begin try datenmodul.SmtpCli.CtrlSocket.Close; except end; end else begin try if datenmodul.SmtpCli.Connected then datenmodul.SmtpCli.Quit; except end; It shall wait for either the timeout or the finish of the e-mail sending process. In the OnRequestDone I've nearly 100% identical code to your mail sending excample (the all in one demo) except that the screen output is missing, the case is put into a try/except and the 10004 error won't lead to a abort of the eventhandler. The handler will set the isemail_connection flag when the quit stage is arrived and will set mailerror to the errorcode and leave the handler if there is some error. I also want the com server to handle the communication to that other program (not it's client) and process (at least partially) the data he gets from it. Unfortunatelly he can raise the event which also triggers a mail sending operation. And then I think the trouble starts. I've implemented there another loop which waits if a mail is currently sent on either the completion (because the same function and thus SmtpClient instance) will be user or a timeout. The waiting loop is similar to the one above. If the mailserver can be reached, all seems to be well, but if I give a non reachable one it miserably fails and the COM-server starts to do weired things! Have you any hints for me? I want the mailing to be partially blocking to be able to handle the other communication but timely tell the user whether seinding was ok or not. And what happens if sending takes place and the program get's closed? Greetings Markus -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
[twsocket] SmtpClient and aborting connection
Hello, Wilfried suggested today that I should use a timer. Basically a good idea, but how to do? The com-server's function should send the mail and either return sort of true if successfull or false if not (it actually would return the mail server's address or a empty string if not successfull). How to do this fashion with the timer based approach? Greetings Markus -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
[twsocket] SmtpClient and aborting connection
Hello, I'm using your SmtpClient component for sending e-mails. I'm trying to built in a failover in my application so that if the first configured mail server can't be reached a second etc. will be tried. The problem is now that I like to cancel the connect if it takes too long. timeout:=timeout+text.Count*10; for i := 0 to length(emailservers) - 1 do begin with datenmodul.SmtpCli do begin try // setup e-mail parameters like server and content mailerror:=0; mailerrortext:=''; isemail_connection:=true; Connect; except mailerror:=1; mailerrortext:=ErrorMessage; try datenmodul.SmtpCli.Quit; except end; continue; end; end; // wait for timeout or success t:=GetTickCount; while ((isemail_connection = true) and (mailerror = 0)) and (((GettickCount = t) and (GetTickCount-t timeout)) xor ((GettickCount t) and (t-GetTickCount timeout))) do begin sleep(10); Application.ProcessMessages; end; // in case of error disconnect asap if (mailerror 0) or (isemail_connection = true) then begin try // datenmodul.SmtpCli.Abort; doesn't work better! datenmodul.SmtpCli.CtrlSocket.cose; except end; end else begin try if datenmodul.SmtpCli.Connected then datenmodul.SmtpCli.Abort; except end; break; end; end; The OnRequestDone is nearly your demo code (the output has been disabled and the case has been packed into a try/except block. I do get 10004 errors or component not ready. It works now since I packed it into try/except blocks but I wonder if this will make further problems. The problems only occur if the first e-mailserver is bot reachable and the connection has to be cancelled. This is in a normal function which makes it blocking for the direct caller but since it's part of a COM-server the COM server could do some things internally while trying to send this e-mail. Greetings Markus PS: somebody should document this component in the wiki, obviously not me! ;-) -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
Re: [twsocket] SmtpClient and aborting connection
The problem is now that I like to cancel the connect if it takes too long. Essentially, you have no control over how long connect takes to time out. There are registry settings relating to TCP attempts and retry delays, but messing with them is dangerous and unpredictable, and effects all Windows applications. The default timeout is usually about 40 seconds, if I remember correctly. I always ping servers first before connecting to them, that way you can set a timeout of a few seconds before trying the next one in the list. Ping will not fail if the server is running, but nothing is listening on the port, but then you should get a much shorter timeout. My threaded ping works asynchronously very nicely, you put the actual connection attempt or ping next server code in the event that's called on successful ping or timeout. MagIpLog on the same page illustrates ping before connection, and reconnection on lost connection. http://www.magsys.co.uk/delphi/magics.asp Angus -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
