Re: [twsocket] No response problem [THttpServer - TCustomLineWSocket]
Ok, thanks so much. I made the changes and it works (though I didn't
tested extensively yet).
For reference, this is what I did:
- use of Connection.PostedDataReceived in the PostedData-event
- I don't use LineMode at all (no change if I do)
- Changing the way I was answering to GET commands from SendStream to
AnswerString. I guess my calculation of the size in the header was
wrong. Anyway it simplifies the code.
I did ICS updates frequently, but I realized I didn't checked the new
webserv demo correctly. I didn't know at all for the AnswerString
function, for example. And if my memory is correct I never used
PostedDataReceived either. First time I downloaded ICS was maybe 4 years
ago or something ;-)
Anyway, it works now, it seems.
Thanks to all the people who help me on this, and a special thanks to
Francois (BTW I won't publish the code since this problem is solved...)
Christophe
Bjørnar Nielsen wrote:
I checked this and I am pretty sure it happens only on second
time connections. When I first do a GET or POST, it always works.
Just out of my head, here is som possible reasons that maybe can cause your
problem.
- The header you generate has wrong content length that tells the length of
the body you send.
- You don't provide a content length in your header, in that case the
browser don't know that he has received all data untill you close the
connection.
- You don't call Connection.PostedDataReceived when all data is received
inside PostedData-event.
If you close the connection, then you should also indicate this happening in
the header ("Connection: Close", instead of "Connection: Keep-Alive")
Regards
Bjørnar
--
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] No response problem [THttpServer - TCustomLineWSocket]
> I checked this and I am pretty sure it happens only on second
> time connections. When I first do a GET or POST, it always works.
Just out of my head, here is som possible reasons that maybe can cause your
problem.
- The header you generate has wrong content length that tells the length of
the body you send.
- You don't provide a content length in your header, in that case the
browser don't know that he has received all data untill you close the
connection.
- You don't call Connection.PostedDataReceived when all data is received
inside PostedData-event.
If you close the connection, then you should also indicate this happening in
the header ("Connection: Close", instead of "Connection: Keep-Alive")
Regards
Bjørnar
--
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] No response problem [THttpServer - TCustomLineWSocket]
> I tried to find a reproductible case, and it seems I found one, with a Very interesting. Can you publish this sample code and related pages so that we can have a look at it and reproduce the problem ourself ? I always say: "If I can reproduce a problem, I can fix it !". -- [EMAIL PROTECTED] http://www.overbyte.be - Original Message - From: "Christophe" <[EMAIL PROTECTED]> To: "ICS support mailing" Sent: Tuesday, June 21, 2005 4:40 AM Subject: Re: [twsocket] No response problem [THttpServer - TCustomLineWSocket] > Ok, still with my problem...sorry it's gonna be a little long mail. > > Bjørnar wrote: > > It would be interesting to se if the lost requests is happening on > > newly created connections, or maybe only on connections that are used > > a second time (many requests on same connection, http1.1 and > > keepalive). > I checked this and I am pretty sure it happens only on second time > connections. When I first do a GET or POST, it always works. > > This brings me to this: > I tried to find a reproductible case, and it seems I found one, with a > solution that works (but it is not nice I think). Anyway, here it is: > > I have a page called login.htm, that contain a form (action="Login") > with a text input, a password input, and a submit button. A page > loginfailed.htm exists and is displayed when the user didn't input the > correct login/password. In this loginfailed.htm there is a link to go > back to login.htm so the user can retry. > When I do the following operations, the bug always happens: > - get login.htm >always OK > - leave username and login blank (or input wrong username/password) > - click Submit, post the data >always OK > - get loginfailed.htm >always OK > - click retry, get login.htm >always OK > - repost some data (any username/password) >ALWAYS BUG: no communication > until timeout. The PostDocument or PostedData functions never execute. > > The functions for GetDocument, PostDocument and PostedData are similar > to the ones of the WebServ example. The password checking (called from > PostedData, when all the data has been received) does a simple test > (using AnsiSameText) and: >if Allowed then >begin > Body := //a string > Header := //another string > Stream.Write(Header[1], Length(Header)); > Stream.Write(Body[1], Length(Body)); > Stream.Seek(0, 0); > Client.DocStream := Stream; > Client.SendStream; >end >else >begin > Client.Document:=HttpServer.DocDir+'\loginfailed.htm'; > Client.SendDocument(httpSendDoc); >end; > > Now, as I said, I found a solution, that is to do a > Client.TriggerSessionClosed(0) after the POST command is handled and the > answer sent to the client. > For now, it seems to works in 100% of the time, but: > 1-Does it sounds you normal to have to use TriggerSessionClosed ? > 2-What are the consequences of using TriggerSessionClosed ? > 3-Is there something "softer" than closing the session ? I tried > TriggerHttpRequestDone but it doesn't work. > > Thanks for all your help ! > Christophe > > Francois Piette wrote: > >>>Does it occurs with the sample "WebServ" delivered with ICS ? > > > > > >>Well it seems it doesn't (at least I didn't experienced the problem > >>yet), which is surprising because my program is quite identical to the > >>demo (I mean, I implemented some functions but nothing that directly > >>change the way THttpServer works). > > > > > > It is likely that you introduced something wrong. Or failed to follow some > > programming rule. > > > > One important thing: never call the message pump, directly or indirectly > > from one of the ICS > > component event. You would get all kind of strange results. Be aware that > > some VCL internally call > > the message pump, like ShowMessage. > > > > -- > > [EMAIL PROTECTED] > > http://www.overbyte.be > > > > > > > -- > 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 > -- 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] No response problem [THttpServer - TCustomLineWSocket]
Ok, still with my problem...sorry it's gonna be a little long mail. Bjørnar wrote: > It would be interesting to se if the lost requests is happening on > newly created connections, or maybe only on connections that are used > a second time (many requests on same connection, http1.1 and > keepalive). I checked this and I am pretty sure it happens only on second time connections. When I first do a GET or POST, it always works. This brings me to this: I tried to find a reproductible case, and it seems I found one, with a solution that works (but it is not nice I think). Anyway, here it is: I have a page called login.htm, that contain a form (action="Login") with a text input, a password input, and a submit button. A page loginfailed.htm exists and is displayed when the user didn't input the correct login/password. In this loginfailed.htm there is a link to go back to login.htm so the user can retry. When I do the following operations, the bug always happens: - get login.htm >always OK - leave username and login blank (or input wrong username/password) - click Submit, post the data >always OK - get loginfailed.htm >always OK - click retry, get login.htm >always OK - repost some data (any username/password) >ALWAYS BUG: no communication until timeout. The PostDocument or PostedData functions never execute. The functions for GetDocument, PostDocument and PostedData are similar to the ones of the WebServ example. The password checking (called from PostedData, when all the data has been received) does a simple test (using AnsiSameText) and: if Allowed then begin Body := //a string Header := //another string Stream.Write(Header[1], Length(Header)); Stream.Write(Body[1], Length(Body)); Stream.Seek(0, 0); Client.DocStream := Stream; Client.SendStream; end else begin Client.Document:=HttpServer.DocDir+'\loginfailed.htm'; Client.SendDocument(httpSendDoc); end; Now, as I said, I found a solution, that is to do a Client.TriggerSessionClosed(0) after the POST command is handled and the answer sent to the client. For now, it seems to works in 100% of the time, but: 1-Does it sounds you normal to have to use TriggerSessionClosed ? 2-What are the consequences of using TriggerSessionClosed ? 3-Is there something "softer" than closing the session ? I tried TriggerHttpRequestDone but it doesn't work. Thanks for all your help ! Christophe Francois Piette wrote: Does it occurs with the sample "WebServ" delivered with ICS ? Well it seems it doesn't (at least I didn't experienced the problem yet), which is surprising because my program is quite identical to the demo (I mean, I implemented some functions but nothing that directly change the way THttpServer works). It is likely that you introduced something wrong. Or failed to follow some programming rule. One important thing: never call the message pump, directly or indirectly from one of the ICS component event. You would get all kind of strange results. Be aware that some VCL internally call the message pump, like ShowMessage. -- [EMAIL PROTECTED] http://www.overbyte.be -- 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] No response problem [THttpServer - TCustomLineWSocket]
> Yes, as I explained in my last mail, when a user makes a > request (GET or > POST or HEAD or whatever), the server get it, and start to analyze it > but stops inside TCustomLineWSocket.TriggerDataAvailable. Ok, I missed that part, my previos message does not explain your problem. In PostedData-event, be sure to call PostedDataReceived on the client-connection (linemode is set to true and FState is set to hcRequest). This will enable the client to receive more requests on same connection (if http1.1 and keepalive). It would be interesting to se if the lost requests is happening on newly created connections, or maybe only on connections that are used a second time (many requests on same connection, http1.1 and keepalive). Regards Bjørnar -- 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] No response problem [THttpServer - TCustomLineWSocket]
> > Does it occurs with the sample "WebServ" delivered with ICS ? > Well it seems it doesn't (at least I didn't experienced the problem > yet), which is surprising because my program is quite identical to the > demo (I mean, I implemented some functions but nothing that directly > change the way THttpServer works). It is likely that you introduced something wrong. Or failed to follow some programming rule. One important thing: never call the message pump, directly or indirectly from one of the ICS component event. You would get all kind of strange results. Be aware that some VCL internally call the message pump, like ShowMessage. -- [EMAIL PROTECTED] http://www.overbyte.be -- 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] No response problem [THttpServer - TCustomLineWSocket]
Francois Piette wrote: The first important thing is: Are you using the very latest ICS version downloaded from my website ? Yes, I re-installed the last version this morning. When users clicks links or post forms in their browsers, sometimes they don't get any answer. By debugging the server I realized that in such a case the OnPostDocument event is never triggered. Do you have a reproductible case ? > No and that's my main problem. I tested this morning, it was awful (like 25% of connections "lost", on two different PCs. But now I'm trying again and it works better (I didn't change anything to the program since this morning, but now I only get very few connections loss). Also, this morning I talked about the OnPostDocument event because at that time, nearly only POST commands had a problem. Now the post commands work totally fine, and the few errors concern basic GET commands. Does it occurs with the sample "WebServ" delivered with ICS ? Well it seems it doesn't (at least I didn't experienced the problem yet), which is surprising because my program is quite identical to the demo (I mean, I implemented some functions but nothing that directly change the way THttpServer works). -- [EMAIL PROTECTED] http://www.overbyte.be - Original Message - From: "Christophe" <[EMAIL PROTECTED]> To: Sent: Monday, June 20, 2005 4:01 AM Subject: [twsocket] No response problem [THttpServer - TCustomLineWSocket] Hi, First of all, I'd like to apologize if my question is inapropriate, it is the first time I am using a mailing list (I usually use php based forums for development issues). I searched a lot about the following problem, but I still don't have a clue of what's happening: I have been developping few applications that use the THttpServer component. I noticed that sometimes (randomly), the server gives no answer to clients. When users clicks links or post forms in their browsers, sometimes they don't get any answer. By debugging the server I realized that in such a case the OnPostDocument event is never triggered. I checked the call stack at that time, and it seems the problem is in TCustomLineWSocket.TriggerDataAvailable (Unit WSocket). At the beginning of this function there is the following test: if (not FLineMode) or (Length(FLineEnd) = 0) or (FSocksState <> socksData) then begin Result := inherited TriggerDataAvailable(Error); Exit; end; I placed breakpoints and I am pretty sure that if FLineMode is false, then there is no problem (the component will continue and send back data to the client). If FLineMode is false, the component will stop here (after the Exit), and will never send anything back to the client browsers (they wait, and, after a while, they fail because of a timeout). It brings 2 questions: - For the same link (GET) or form (POST), why does sometimes FlineMode is true and sometimes false ? - How to force FLineMode to be true, or more generally how to solve such a problem. (I tried to do a (Client as THTTPConnection).LineMode:=true in the OnClientConnect event but it doesn't change a thing). PS: It is the first time I checked ICS source, so my analysis of the problem is maybe totally wrong. PS2: I tested this on two different PCs with WindowsXP (no firewall, no antivirus) on a LAN. I re-downloaded ICS today to be sure, but the problem is still there. Thank you, Christophe -- 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 -- 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] No response problem [THttpServer - TCustomLineWSocket]
Bjørnar Nielsen wrote: When users clicks links or post forms in their browsers, sometimes they don't get any answer. By debugging the server I realized that in such a case the OnPostDocument event is never triggered. Are you sure the request you don't get an answer from is received on the server? Yes, as I explained in my last mail, when a user makes a request (GET or POST or HEAD or whatever), the server get it, and start to analyze it but stops inside TCustomLineWSocket.TriggerDataAvailable. When you run a server on a non-server-platform you might miss some requests when many requests arrive at the same time. On a non-server-platform (w2000, XP etc) there is a listen backlog set to 5. That means that 5 connects is queued by the os if your server is not ready to accept the connection yet. The sixth connection will be lost. On a server-platform (w2000 server, w2003 server etc), this backlog is set to 200. > Well I can understand that, except that this problem occurs even when I do debugging (which means only one client, on the local machine). Also, I checked in the MS event manager (I guess if windows drops some connections it would place an entry here), but I found nothing. Regards Bjørnar -- 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] No response problem [THttpServer - TCustomLineWSocket]
Hello Christophe, > - How to force FLineMode to be true, or more generally how to solve such > a problem. (I tried to do a (Client as THTTPConnection).LineMode:=true > in the OnClientConnect event but it doesn't change a thing). In OnPostDocument you have to set LineMode to False (since binary data can be posted), and when data posting is complete you have to set LineMode of that data socket back to true. --- Rgds, Wilfried 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
Re: [twsocket] No response problem [THttpServer - TCustomLineWSocket]
The first important thing is: Are you using the very latest ICS version downloaded from my website ? > When users clicks links or post forms in their browsers, sometimes they > don't get any answer. By debugging the server I realized that in such a > case the OnPostDocument event is never triggered. Do you have a reproductible case ? Does it occurs with the sample "WebServ" delivered with ICS ? -- [EMAIL PROTECTED] http://www.overbyte.be - Original Message - From: "Christophe" <[EMAIL PROTECTED]> To: Sent: Monday, June 20, 2005 4:01 AM Subject: [twsocket] No response problem [THttpServer - TCustomLineWSocket] > Hi, > > First of all, I'd like to apologize if my question is inapropriate, it > is the first time I am using a mailing list (I usually use php based > forums for development issues). > > I searched a lot about the following problem, but I still don't have a > clue of what's happening: > > I have been developping few applications that use the THttpServer > component. I noticed that sometimes (randomly), the server gives no > answer to clients. > When users clicks links or post forms in their browsers, sometimes they > don't get any answer. By debugging the server I realized that in such a > case the OnPostDocument event is never triggered. > > I checked the call stack at that time, and it seems the problem is in > TCustomLineWSocket.TriggerDataAvailable (Unit WSocket). At the beginning > of this function there is the following test: > if (not FLineMode) or (Length(FLineEnd) = 0) or (FSocksState <> socksData) > then begin >Result := inherited TriggerDataAvailable(Error); >Exit; > end; > > I placed breakpoints and I am pretty sure that if FLineMode is false, > then there is no problem (the component will continue and send back data > to the client). > If FLineMode is false, the component will stop here (after the Exit), > and will never send anything back to the client browsers (they wait, > and, after a while, they fail because of a timeout). > > It brings 2 questions: > - For the same link (GET) or form (POST), why does sometimes FlineMode > is true and sometimes false ? > - How to force FLineMode to be true, or more generally how to solve such > a problem. (I tried to do a (Client as THTTPConnection).LineMode:=true > in the OnClientConnect event but it doesn't change a thing). > > PS: It is the first time I checked ICS source, so my analysis of the > problem is maybe totally wrong. > PS2: I tested this on two different PCs with WindowsXP (no firewall, no > antivirus) on a LAN. I re-downloaded ICS today to be sure, but the > problem is still there. > > Thank you, > Christophe > > -- > 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 > -- 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] No response problem [THttpServer - TCustomLineWSocket]
> When users clicks links or post forms in their browsers, > sometimes they don't get any answer. By debugging the server > I realized that in such a case the OnPostDocument event is > never triggered. Are you sure the request you don't get an answer from is received on the server? When you run a server on a non-server-platform you might miss some requests when many requests arrive at the same time. On a non-server-platform (w2000, XP etc) there is a listen backlog set to 5. That means that 5 connects is queued by the os if your server is not ready to accept the connection yet. The sixth connection will be lost. On a server-platform (w2000 server, w2003 server etc), this backlog is set to 200. Regards Bjørnar -- 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] No response problem [THttpServer - TCustomLineWSocket]
Hi, First of all, I'd like to apologize if my question is inapropriate, it is the first time I am using a mailing list (I usually use php based forums for development issues). I searched a lot about the following problem, but I still don't have a clue of what's happening: I have been developping few applications that use the THttpServer component. I noticed that sometimes (randomly), the server gives no answer to clients. When users clicks links or post forms in their browsers, sometimes they don't get any answer. By debugging the server I realized that in such a case the OnPostDocument event is never triggered. I checked the call stack at that time, and it seems the problem is in TCustomLineWSocket.TriggerDataAvailable (Unit WSocket). At the beginning of this function there is the following test: if (not FLineMode) or (Length(FLineEnd) = 0) or (FSocksState <> socksData) then begin Result := inherited TriggerDataAvailable(Error); Exit; end; I placed breakpoints and I am pretty sure that if FLineMode is false, then there is no problem (the component will continue and send back data to the client). If FLineMode is false, the component will stop here (after the Exit), and will never send anything back to the client browsers (they wait, and, after a while, they fail because of a timeout). It brings 2 questions: - For the same link (GET) or form (POST), why does sometimes FlineMode is true and sometimes false ? - How to force FLineMode to be true, or more generally how to solve such a problem. (I tried to do a (Client as THTTPConnection).LineMode:=true in the OnClientConnect event but it doesn't change a thing). PS: It is the first time I checked ICS source, so my analysis of the problem is maybe totally wrong. PS2: I tested this on two different PCs with WindowsXP (no firewall, no antivirus) on a LAN. I re-downloaded ICS today to be sure, but the problem is still there. Thank you, Christophe -- 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
