Re: Apache server returns early before process is complete

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Thanks, all.
Is that Apache timeout controlled by its configuration "Timeout"?
I don't think it has anything to do with modPerl. Am I missing something?
Thanks.

On Wed, Apr 23, 2025 at 1:41=E2=80=AFPM Mithun Bhattacharya <[email protected]=
om>
wrote:

> Timeout happens because of how we handle the request. Timeout is basicall=
y
> no response came back. Why that happens is because we think we want to ha=
ve
> a correct response. Unfortunately for long running requests the correct
> response shouldn't be via http response code or we face situations like
> this. Instead reply with a 200 OK immediately and then provide correct
> status in the message body. Once a response code/header has been sent
> timeout won't trigger and you could potentially hold the connection for
> hours without a problem.
>
> On Wed, Apr 23, 2025, 9:32=E2=80=AFAM Andreas Mock <[email protected]> =
wrote:
>
>> Hi Joseph,
>>
>> your description is very vague, so can only answer on some assumptions:
>>
>> It sounds like a timeout is fired somewhere.
>>
>> Best advice in these situations: Log as many steps as you can. Keep your
>> eyes open on TCP/IP and higher level timeouts.
>>
>> Declare only ONE instance responsible for a retry: Either the app server
>> calling the dispatcher with several tries or the dispatcher trying for
>> himself. Not both.
>>
>> Best regards
>> Andreas
>>
>>
>> Am 23.04.2025 um 16:21 schrieb Joseph He:
>> > All, good day.
>> >
>> > Here is the issue I have.
>> > My entire application is running on ModPerl/Apache environment.
>> > I send Http::Request with data load from my App server to a dispatch
>> > server thru LWP::UserAgent, I set the timeout 600 seconds.
>> >
>> > The dispatch server is supposed to manipulate the data and send the
>> > data to an external SFTP server. Because the SFTP can fail, it will
>> > keep trying up to 4 times with 30 seconds sleep in case that SFTP
>> > connection fails.
>> >
>> > Recently, I found that I uploaded the file twice sometimes. I figured
>> > out the root cause is that my Dispatch server returns 'failure' at 6
>> > minutes while it keeps trying to do the SFTP. The App server
>> > received HTTP::Response with error status so it issued another call to
>> > send data. It turns out I uploaded the identified file twice.
>> >
>> > Anybody has this sort of experience? Why does the dispatch server
>> > return 'error' while it still processes the data?
>> >
>> > Thanks a lot,
>> > Joseph
>> >
>>
>

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<div dir=3D"ltr">Thanks, all.<div>Is that Apache timeout controlled by its =
configuration=C2=A0&quot;Timeout&quot;?=C2=A0</div><div>I don&#39;t think i=
t has anything to do with modPerl. Am I=C2=A0missing something?</div><div>T=
hanks.</div></div><br><div class=3D"gmail_quote gmail_quote_container"><div=
 dir=3D"ltr" class=3D"gmail_attr">On Wed, Apr 23, 2025 at 1:41=E2=80=AFPM M=
ithun Bhattacharya &lt;<a href=3D"mailto:[email protected]">[email protected]=
</a>&gt; wrote:<br></div><blockquote class=3D"gmail_quote" style=3D"margin:=
0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">=
<div dir=3D"auto">Timeout happens because of how we handle the request. Tim=
eout is basically no response came back. Why that happens is because we thi=
nk we want to have a correct response. Unfortunately for long running reque=
sts the correct response shouldn&#39;t be via http response code or we face=
 situations like this. Instead reply with a 200 OK immediately and then pro=
vide correct status in the message body. Once a response code/header has be=
en sent timeout won&#39;t trigger and you could potentially hold the connec=
tion for hours without a problem.</div><br><div class=3D"gmail_quote"><div =
dir=3D"ltr" class=3D"gmail_attr">On Wed, Apr 23, 2025, 9:32=E2=80=AFAM Andr=
eas Mock &lt;<a href=3D"mailto:[email protected]" target=3D"_blank">andre=
[email protected]</a>&gt; wrote:<br></div><blockquote class=3D"gmail_quote" st=
yle=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padd=
ing-left:1ex">Hi Joseph,<br>
<br>
your description is very vague, so can only answer on some assumptions:<br>
<br>
It sounds like a timeout is fired somewhere.<br>
<br>
Best advice in these situations: Log as many steps as you can. Keep your <b=
r>
eyes open on TCP/IP and higher level timeouts.<br>
<br>
Declare only ONE instance responsible for a retry: Either the app server <b=
r>
calling the dispatcher with several tries or the dispatcher trying for <br>
himself. Not both.<br>
<br>
Best regards<br>
Andreas<br>
<br>
<br>
Am 23.04.2025 um 16:21 schrieb Joseph He:<br>
&gt; All, good day.<br>
&gt;<br>
&gt; Here is the issue I have.<br>
&gt; My entire application is running on ModPerl/Apache environment.<br>
&gt; I send Http::Request with data load from my App server to a dispatch <=
br>
&gt; server thru LWP::UserAgent, I set the timeout 600 seconds.<br>
&gt;<br>
&gt; The dispatch server is supposed to manipulate the data and send the <b=
r>
&gt; data to an external SFTP server. Because the SFTP can fail, it will <b=
r>
&gt; keep trying up to 4 times with 30 seconds sleep in case that SFTP <br>
&gt; connection fails.<br>
&gt;<br>
&gt; Recently, I found that I uploaded the file twice sometimes. I figured =
<br>
&gt; out the root cause is that my Dispatch server returns &#39;failure&#39=
; at 6 <br>
&gt; minutes while it keeps trying to do the SFTP. The App server <br>
&gt; received=C2=A0HTTP::Response with error status so it issued another ca=
ll to <br>
&gt; send data. It turns out I uploaded the identified file twice.<br>
&gt;<br>
&gt; Anybody has this sort of experience? Why does the dispatch=C2=A0server=
 <br>
&gt; return &#39;error&#39; while it still processes the data?<br>
&gt;<br>
&gt; Thanks a lot,<br>
&gt; Joseph<br>
&gt;<br>
</blockquote></div>
</blockquote></div>

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