soaplite-devel

[Soaplite-devel] bug: SOAP calls fail when folder with the same name as the dispatch_to location exists

[Tom S. <acc...@ze...>]

Hi All,

I posted a question to the mod_perl mailing list but it would be better
served here.

8<-- snip --------------------

Im having some mod_perl2 wierdness. Im trying to run some SOAP requests and
Im getting odd things happening.

Is there any reason that I should be experiencing intermittant issues
dispatching SOAP methods to my class?

Sometimes the methods work fine and sometimes they don't.

When they don't I get the error returned in a fault string:
Failed to locate method (getSession) in class (TestSpace) at
/usr/local/lib/perl5/site_perl/5.8.8/SOAP/Lite.pm line 2586.

And then sometimes it all works perfectly.

Ive tried boiling all this down to a simple test case.

TestSpace.pm
------------
package MediaSpace;

sub getSession {
    return 1;
}

1;

I would estimate that 50% of the requests fail.

Im using Apache-2.2.4 PreforkMPM/Perl 5.8.8 with no threads support, and
mod_perl-2.0.3.

Any ideas would be welcomed at this point in time as Im out of ideas.

Cheers,
Tom

8<-- snip --------------------



I did some testing and found that the reason some of the requests and some
didn't failed was because of the number of httpd processes.  I cut those
down and found that the problem was there all the time.
 
After some more testing I found the solution by accident.

I should probably explain what my setup is doing.

/viewspace generates some HTML, which in turn loads a piece of Flash into
the browser.  This flash content once loaded, sends some SOAP calls to the
server.

It seems that the combination of running the handler to generate the HTML,
followed quickly by the hander for the soap calls generates the conditions
for this error. A little bit more testing and I found that slightly loading
The webserver triggered this condition and once it was triggered any request
to the soap handler failed.

If I rename my MediaSpace folder, update the /viewspace handler and
httpd.conf to reflect the change my /soap handler works perfectly.  Is the
/soap handler having some troubles processing the call dispatch if a folder
of the same name exists in the same location? It certainly looks that way. 

Anyone else care to verify?

My actual filestructure is like so:

/webhome/MediaSpace.pm           -> used to handle SOAP requests
/webhome/MediaSpace/ViewSpace.pm -> mod_perl handler to generate HTML
/webhome/MediaSpace/Media.pm     -> media functions
Some other files...
.
etc

MediaSpace.pm
-------------
package MediaSpace;

sub getSession {
    return 1;
}

1;

My httpd.conf SOAP entry and mod_perl handler for the HTML generation:
<Location /soap>
    SetHandler perl-script
    PerlResponseHandler Apache2::SOAP
    PerlSetVar dispatch_to '/webhome/'
    PerlSetVar options "compress_threshold => 1000"
</Location>

Debian on a 2.6 kernel
Apache 2.2.4 (Prefork MPM) / Perl 5.8.8 (NO threads support) / mod_perl 2.03
SOAP::Lite v0.69
Apache2::SOAP v0.72

Cheers,
Tom

Re: [Soaplite-devel] bug: SOAP calls fail when folder with thesame name as the dispatch_to location exists

[Tom S. <acc...@ze...>]

Thanks for the reply.

I am using SOAP::Lite under mod_perl, not CGI.

Ive tried altering my SOAP requests but I still get this intermittant
problem.  I have used your SOAP requests as models and the problem
continues.  I have further updated my SOAP requests to include a full =
URI as
per the SOAP spec.

I just tried it now and made two requests.  The first failed...the =
second
worked.  As you suggested I set 'MaxClients 1' in my httpd.conf.
=20
Heres the trace...
------------------

HTTP-Trace-Version: 1.0
Generator: Charles/3.0.2

Method: POST
Protocol-Version: HTTP/1.1
Protocol: http
Host: echo.localhost
File: /soap
Remote-Address: 172.30.6.60
Client-Address: 127.0.0.1
Start-Time: 2007-05-08T10:46:56.250+01:00
Response-Time: 2007-05-08T10:46:56.471+01:00
End-Time: 2007-05-08T10:46:56.481+01:00
Request-Header-Size: 668
Response-Header-Size: 248
Request-Body-Size: 454
Response-Body-Size: 576
Request-Body-Decoded: false
Response-Body-Decoded: false
Request-Header:<<--EOF-1178618598002-
POST /soap HTTP/1.1
Host: echo.localhost
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.3)
Gecko/20070309 Firefox/2.0.0.3
Accept:
application/x-shockwave-flash,text/xml,application/xml,application/xhtml+=
xml
,text/html;q=3D0.9,text/plain;q=3D0.8,image/png,*/*;q=3D0.5
Accept-Language: en-us,en;q=3D0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=3D0.7,*;q=3D0.7
Keep-Alive: 300
Referer: http://echo.localhost/interface/interface.swf?spaceid=3D
Content-type: text/xml; charset=3Dutf-8
SOAPAction: "http://echo.localhost/echo/getSession"
Content-length: 454
Pragma: no-cache
Cache-Control: no-cache


--EOF-1178618598002-
Response-Header:<<--EOF-1178618598002-
HTTP/1.1 200 OK
Date: Tue, 08 May 2007 09:45:42 GMT
Server: Apache/2.2.4 (Unix) DAV/2 PHP/5.2.1 mod_apreq2-20051231/2.6.0
mod_perl/2.0.3 Perl/v5.8.8
Content-Length: 576
Content-Type: text/xml; charset=3Dutf-8
SOAPServer: SOAP::Lite/Perl/0.69
Expires: 0
Cache-Control: no-cache


--EOF-1178618598002-
Request-Body:<<--EOF-1178618598002-
<?xml version=3D"1.0" encoding=3D"utf-8"?> <SOAP-ENV:Envelope
xmlns:xsi=3D"http://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd=3D"http://www.w3.org/2001/XMLSchema"
xmlns:SOAP-ENV=3D"http://schemas.xmlsoap.org/soap/envelope/"><SOAP-ENV:Bo=
dy
xmlns:ns1=3D"http://echo.localhost/echo"><ns1:getSession
SOAP-ENV:encodingStyle=3D"http://schemas.xmlsoap.org/soap/encoding/"><cli=
entid
xsi:type=3D"xsd:string"
/></ns1:getSession></SOAP-ENV:Body></SOAP-ENV:Envelope>
--EOF-1178618598002-
Response-Body:<<--EOF-1178618598002-
<?xml version=3D"1.0" encoding=3D"UTF-8"?><soap:Envelope
xmlns:xsi=3D"http://www.w3.org/2001/XMLSchema-instance"
xmlns:soapenc=3D"http://schemas.xmlsoap.org/soap/encoding/"
xmlns:xsd=3D"http://www.w3.org/2001/XMLSchema"
soap:encodingStyle=3D"http://schemas.xmlsoap.org/soap/encoding/"
xmlns:soap=3D"http://schemas.xmlsoap.org/soap/envelope/"><soap:Body><soap=
:Faul
t><faultcode>soap:Client</faultcode><faultstring>Failed to locate method
(getSession) in class (echo) at
/usr/local/lib/perl5/site_perl/5.8.8/SOAP/Lite.pm line 2587.
</faultstring></soap:Fault></soap:Body></soap:Envelope>
--EOF-1178618598002-


<< SECOND REQUEST A FEW MINS LATER

Method: POST
Protocol-Version: HTTP/1.1
Protocol: http
Host: echo.localhost
File: /soap
Remote-Address: 172.30.6.60
Client-Address: 127.0.0.1
Start-Time: 2007-05-08T10:52:43.420+01:00
Response-Time: 2007-05-08T10:52:43.910+01:00
End-Time: 2007-05-08T10:52:43.910+01:00
Request-Header-Size: 668
Response-Header-Size: 248
Request-Body-Size: 454
Response-Body-Size: 889
Request-Body-Decoded: false
Response-Body-Decoded: false
Request-Header:<<--EOF-1178618598002-
POST /soap HTTP/1.1
Host: echo.localhost
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.3)
Gecko/20070309 Firefox/2.0.0.3
Accept:
application/x-shockwave-flash,text/xml,application/xml,application/xhtml+=
xml
,text/html;q=3D0.9,text/plain;q=3D0.8,image/png,*/*;q=3D0.5
Accept-Language: en-us,en;q=3D0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=3D0.7,*;q=3D0.7
Keep-Alive: 300
Referer: http://echo.localhost/interface/interface.swf?spaceid=3D
Content-type: text/xml; charset=3Dutf-8
SOAPAction: "http://echo.localhost/echo/getSession"
Content-length: 454
Pragma: no-cache
Cache-Control: no-cache


--EOF-1178618598002-
Response-Header:<<--EOF-1178618598002-
HTTP/1.1 200 OK
Date: Tue, 08 May 2007 09:51:29 GMT
Server: Apache/2.2.4 (Unix) DAV/2 PHP/5.2.1 mod_apreq2-20051231/2.6.0
mod_perl/2.0.3 Perl/v5.8.8
Content-Length: 889
Content-Type: text/xml; charset=3Dutf-8
SOAPServer: SOAP::Lite/Perl/0.69
Expires: 0
Cache-Control: no-cache


--EOF-1178618598002-
Request-Body:<<--EOF-1178618598002-
<?xml version=3D"1.0" encoding=3D"utf-8"?> <SOAP-ENV:Envelope
xmlns:xsi=3D"http://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd=3D"http://www.w3.org/2001/XMLSchema"
xmlns:SOAP-ENV=3D"http://schemas.xmlsoap.org/soap/envelope/"><SOAP-ENV:Bo=
dy
xmlns:ns1=3D"http://echo.localhost/echo"><ns1:getSession
SOAP-ENV:encodingStyle=3D"http://schemas.xmlsoap.org/soap/encoding/"><cli=
entid
xsi:type=3D"xsd:string"
/></ns1:getSession></SOAP-ENV:Body></SOAP-ENV:Envelope>
--EOF-1178618598002-
Response-Body:<<--EOF-1178618598002-
<?xml version=3D"1.0" encoding=3D"UTF-8"?><soap:Envelope
xmlns:namesp1=3D"http://namespaces.soaplite.com/perl"
xmlns:xsi=3D"http://www.w3.org/2001/XMLSchema-instance"
xmlns:soapenc=3D"http://schemas.xmlsoap.org/soap/encoding/"
xmlns:xsd=3D"http://www.w3.org/2001/XMLSchema"
soap:encodingStyle=3D"http://schemas.xmlsoap.org/soap/encoding/"
xmlns:soap=3D"http://schemas.xmlsoap.org/soap/envelope/"><soap:Body><getS=
essio
nResponse xmlns=3D"http://echo.localhost/echo"><getSessionObject
xsi:type=3D"namesp1:getSessionObject"><SessionMeta
xsi:type=3D"namesp1:SessionMeta"><hash
xsi:type=3D"xsd:string">2710c1b6d0001d394af973a96cb8252d</hash><uid
xsi:type=3D"xsd:string">guest</uid><created
xsi:type=3D"xsd:epoch">1178617889</created><poll
xsi:type=3D"xsd:epoch">1178617889</poll><timeout
xsi:type=3D"xsd:epoch">1178618489</timeout></SessionMeta></getSessionObje=
ct></
getSessionResponse></soap:Body></soap:Envelope>
--EOF-1178618598002-



As you can see the SOAP request does not change.

As I said before if I rename the folder (echo) to sometehing else =
everything
works perfectly.

Cheers,
Tom
-----Original Message-----
From: J=F6rg Prante [mailto:joe...@ne...]=20
Sent: 27 April 2007 21:26
To: Tom Shaw
Subject: Re: [Soaplite-devel] bug: SOAP calls fail when folder with =
thesame
name as the dispatch_to location exists

Hello,

> When they don't I get the error returned in a fault string:
> Failed to locate method (getSession) in class (TestSpace) at
> /usr/local/lib/perl5/site_perl/5.8.8/SOAP/Lite.pm line 2586.

This is typically an misconfigured SOAP client call, without namespace
and incorrect or empty URI in SOAPAction.

> Im using Apache-2.2.4 PreforkMPM/Perl 5.8.8 with no threads support, =
and
> mod_perl-2.0.3.

Same here.

> /viewspace generates some HTML, which in turn loads a piece of Flash =
into
> the browser.  This flash content once loaded, sends some SOAP calls to =
the
> server.

Do you really store your Perl modules right on your web server directory
where your HTML is generated? This is a bad idea.

> It seems that the combination of running the handler to generate the =
HTML,
> followed quickly by the hander for the soap calls generates the =
conditions
> for this error. A little bit more testing and I found that slightly
loading
> The webserver triggered this condition and once it was triggered any
request
> to the soap handler failed.

Test with "MaxClients 1" in your httpd.conf and it will fail straight.
You see the Apache children loading mod_perl resources during their
lifecycles.

> If I rename my MediaSpace folder, update the /viewspace handler and
> httpd.conf to reflect the change my /soap handler works perfectly.  Is =
the
> /soap handler having some troubles processing the call dispatch if a
folder
> of the same name exists in the same location? It certainly looks that =
way.

>
> Anyone else care to verify?

Please provide your SOAP client calls and/or SOMs. In particular, the
SOAPAction header. It is impossible to verify without being able to
reproduce.

Here is my test scenario from what I could understand from your
description.


ll /var/www/cgi-bin/

drwxr-xr-x 2 apache apache 4096 27. Apr 21:41 Echo
-rwx------ 1 apache apache   87 27. Apr 21:27 Echo.pm


httpd.conf:
-------------------
<Location /soaptest>
        SetHandler perl-script
        PerlResponseHandler Apache2::SOAP
        PerlSetVar dispatch_to '/var/www/cgi-bin/'
        PerlSetVar options "compress_threshold =3D> 1000"
</Location>
-------------------
Echo.pm:
-------------------
package Echo;
sub echo {
   my ($self, @args) =3D @_;
   return join(",", @args);
}

1;
-------------------
echoclient.pl:
-------------------
#!/usr/bin/perl
use SOAP::Lite +trace =3D> 'debug';

my $soap =3D SOAP::Lite
  ->readable(1)
  ->uri("urn:Echo")
  ->proxy("http://localhost/soaptest");
my $som =3D $soap->echo(SOAP::Data->name("whatToEcho"=3D>"Hello =
World"));
print "The response from the server was:\n".$som->result."\n";
-------------------

Invoking the SOAP client echoclient.pl gives:

SOAP::Transport::HTTP::Client::send_receive: POST
http://localhost/soaptest HTTP/1.1
Accept: text/xml
Accept: multipart/*
Accept: application/soap
Content-Length: 506
Content-Type: text/xml
SOAPAction: "urn:Echo#echo"

<?xml version=3D"1.0" encoding=3D"UTF-8"?>
<soap:Envelope=20
    xmlns:xsi=3D"http://www.w3.org/2001/XMLSchema-instance"=20
    xmlns:soapenc=3D"http://schemas.xmlsoap.org/soap/encoding/"=20
    xmlns:xsd=3D"http://www.w3.org/2001/XMLSchema"=20
    soap:encodingStyle=3D"http://schemas.xmlsoap.org/soap/encoding/"=20
    xmlns:soap=3D"http://schemas.xmlsoap.org/soap/envelope/">
  <soap:Body>
    <echo xmlns=3D"urn:Echo">
      <whatToEcho xsi:type=3D"xsd:string">Hello World</whatToEcho>
    </echo>
  </soap:Body>
</soap:Envelope>
SOAP::Transport::HTTP::Client::send_receive: HTTP/1.1 200 OK
Connection: close
Date: Fri, 27 Apr 2007 20:14:28 GMT
Server: Apache/2.2.4 (Fedora)
Content-Length: 469
Content-Type: text/xml; charset=3Dutf-8
Client-Date: Fri, 27 Apr 2007 20:14:28 GMT
Client-Peer: 127.0.0.1:80
Client-Response-Num: 1
SOAPServer: SOAP::Lite/Perl/0.69

<?xml version=3D"1.0" encoding=3D"UTF-8"?><soap:Envelope
xmlns:xsi=3D"http://www.w3.org/2001/XMLSchema-instance"
xmlns:soapenc=3D"http://schemas.xmlsoap.org/soap/encoding/"
xmlns:xsd=3D"http://www.w3.org/2001/XMLSchema"
soap:encodingStyle=3D"http://schemas.xmlsoap.org/soap/encoding/"
xmlns:soap=3D"http://schemas.xmlsoap.org/soap/envelope/"><soap:Body><echo=
Respo
nse xmlns=3D"urn:Echo"><s-gensym3 xsi:type=3D"xsd:string">Hello
World</s-gensym3></echoResponse></soap:Body></soap:Envelope>
The response from the server was:
Hello World

Fedora Core 6
Perl 5.8.8
SOAP::Lite 0.69
httpd 2.2.4 (prefork)
mod_perl 2.0.3
Apache2::SOAP 0.72