We should raise an error when wkhtmltopdf fails

[Alexis de Lattre]

Dear Camptocamp dream team,

In c2c-financial-addons/account_financial_report_webkit/report/webkit_parser_header_fix.py, there is the following code arround line 119 :

        try:
            status = subprocess.call(command, stderr=subprocess.PIPE) # ignore stderr
            if status :
                raise except_osv(
                                _('Webkit raise an error' ),
                                status
                            )
        except Exception:
            for f_to_del in file_to_del :
                os.unlink(f_to_del)

The problem is the following :
if the wkhtmltopdf command fails, then status <> 0 and you raise an exception ; this exception is catched and you remove the HTML file... and then the program goes on ! No error message is displayed to the user !

In my case, wkhtmltopdf failed with the error "wkhtmltopdf: cannot connect to X server"... and it eventually crashes later on in the code and I get the Publisher warranty error pop-up with message :

OpenERP-Client Version : 6.1.1
Last revision No. & ID :2059 <email address hidden>
<ProtocolError for localhost:9998/xmlrpc/report: 500 INTERNAL SERVER ERROR>

and on the server side, the message was :

2012-05-23 17:10:33,208 20396 ERROR ? openerp.service.web_services: Exception: [Errno 2] No such file or directory: '/tmp/webkit.tmp.McE6mh.pdf'
Traceback (most recent call last):
  File "/opt/openerp/prod/server/openerp/service/web_services.py", line 727, in go
    (result, format) = obj.create(cr, uid, ids, datas, context)
  File "/opt/openerp/prod/addons/report_webkit/webkit_report.py", line 325, in create
    result = self.create_source_pdf(cursor, uid, ids, data, report_xml, context)
  File "/opt/openerp/prod/server/openerp/report/report_sxw.py", line 511, in create_source_pdf
    return self.create_single_pdf(cr, uid, ids, data, report_xml, context)
  File "/opt/openerp/prod/c2c-financial-addons-6.1/account_financial_report_webkit/report/webkit_parser_header_fix.py", line 223, in create_single_pdf
    pdf = self.generate_pdf(bin, report_xml, head, foot, htmls)
  File "/opt/openerp/prod/c2c-financial-addons-6.1/account_financial_report_webkit/report/webkit_parser_header_fix.py", line 130, in generate_pdf
    pdf = file(out_filename, 'rb').read()
IOError: [Errno 2] No such file or directory: '/tmp/webkit.tmp.McE6mh.pdf'
2012-05-23 17:10:33,966 20396 ERROR ? openerp.netsvc: 2
No such file or directory
(<type 'exceptions.IOError'>, IOError(2, 'No such file or directory'), <traceback object at 0xb194ae3c>)
2012-05-23 17:10:33,983 20396 INFO ? werkzeug: 127.0.0.1 - - [23/May/2012 17:10:33] "POST /xmlrpc/report HTTP/1.1" 500 -
2012-05-23 17:10:33,993 20396 ERROR ? werkzeug: Error on request:
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/werkzeug/serving.py", line 159, in run_wsgi
    execute(app)
  File "/usr/local/lib/python2.7/dist-packages/werkzeug/serving.py", line 146, in execute
    application_iter = app(environ, start_response)
  File "/opt/openerp/prod/server/openerp/wsgi/core.py", line 397, in application
    result = handler(environ, start_response)
  File "/opt/openerp/prod/server/openerp/wsgi/core.py", line 222, in wsgi_xmlrpc_legacy
    return xmlrpc_return(start_response, path, method, params, True)
  File "/opt/openerp/prod/server/openerp/wsgi/core.py", line 83, in xmlrpc_return
    response = xmlrpc_handle_exception_legacy(e)
  File "/opt/openerp/prod/server/openerp/wsgi/core.py", line 124, in xmlrpc_handle_exception_legacy
    fault = xmlrpclib.Fault('warning -- ' + e.name + '\n\n' + e.value, '')
TypeError: coercing to Unicode: need string or buffer, tuple found

The enclosed patch will block the execution if wkhtmltopdf fails and will display the error code to the user in a nice pop-up.

It would be even better to display the output of stderr, so that it's easier for the user to understand the cause of the issue. With my enclosed patch, the pop-up would say "The command 'wkhtmltopdf' failed with error code = 1", which won't help me solve the issue. If I get the message "The command 'wkhtmltopdf' failed with the following message : wkhtmltopdf: cannot connect to X server", then it would be easier for me to solve it. But I am not an expert of subprocess.call and I don't know how it can be done.

The enclosed patch has been successfully tested on the branch lp:c2c-financial-addons/6.1/

P.S. : for those we have the same error with wkhtmltopdf, here is the explaination : http://code.google.com/p/wkhtmltopdf/issues/detail?id=3

[Alexandre Fayolle - camptocamp (alexandre-fayolle-c2c)]

On mer. 23 mai 2012 19:28:33 CEST, Alexis de Lattre wrote:
> ** Patch added: "patch-c2c-financial-addons-6.1_webkit-error.diff"
> https://bugs.launchpad.net/bugs/1003563/+attachment/3159753/+files/patch-c2c-financial-addons-6.1_webkit-error.diff
>

Thanks for the bug report Alexis.

I'm going to look into this, and propose an updated version of the
patch to include the output of the failing command. Stay tuned.

--
Alexandre Fayolle
Chef de Projet
Tel : + 33 (0)4 79 26 57 92

Camptocamp France SAS
Savoie Technolac, BP 352
73377 Le Bourget du Lac Cedex
http://www.camptocamp.com

[Alexandre Fayolle - camptocamp (alexandre-fayolle-c2c)]

Alexis,

I've just submitted a fix for this bug as a merge request. Could you take the time to check that it does fix your issue (I don't have an instance at hand with no X server which I can use to generate a systematic error) and report as a review of https://code.launchpad.net/~c2c/c2c-financial-addons/6.1-fix-1003563/+merge/107169 ?

Thanks in advance

--
Alexandre

[Alexandre Fayolle - camptocamp (alexandre-fayolle-c2c)]

it looks like I goofed my merge request. Will try again. Sorry for the inconvenience.

[Alexandre Fayolle - camptocamp (alexandre-fayolle-c2c)]

looks better now.

[Alexis de Lattre (alexis-via)]

OK, I added my comment on the merge proposal (according to my tests, the issue is still present).

[Guewen Baconnier @ Camptocamp (gbaconnier-c2c)]

Can we put this bug to "Fix Released" ?

[Alexandre Fayolle - camptocamp (alexandre-fayolle-c2c)]

done