Using ReportLab with ZipImport

[Arun Shanker Prasad]

Hi,

I have a requirement to generate dynamic PDFs from HTML source. I
included the Pisa, html5lib and the reportlab packages for this.
Everything works fine in the local environment as long I keep all the
packages in the initial source ie I do not zip it.

Keeping the whole ReportLab package (204 files) might take me way
close to the allowed file limit. I tried to convert the ReportLab
package into a zip and use zipimport to use it. This causes the
following error,

AttributeError: 'HardenedModulesHook' object has no attribute '_files'

My source where the imports are called,
import sys
sys.path.insert(0, 'ho.zip')
sys.path.insert(0, 'html5lib.zip')
sys.path.insert(0, 'sx.zip')
sys.path.insert(0, 'reportlab.zip')
import ho.pisa as pisa

Googled a bit for the solution found another mention of this in issue
tracker,
http://code.google.com/p/googleappengine/issues/detail?id=1085.

Can anyone help me get around this problem? I have seen many use
reportlab in Google App Engine how do you guys get around this issue??

Any help will be greatly appreciated.

Thanks,
Arun Shanker Prasad.

[Arun Shanker Prasad]

Hi,

Anyone got any work-around for my situation? I am stuck at this
point...

Thanks,
Arun Shanker Prasad.

On Apr 6, 5:12 pm, Arun Shanker Prasad <ArunShankerPra...@gmail.com>
wrote:

> Hi,
>
> I have a requirement to generate dynamic PDFs from HTML source. I
> included the Pisa, html5lib and the reportlab packages for this.
> Everything works fine in the local environment as long I keep all the
> packages in the initial source ie I do not zip it.
>
> Keeping the whole ReportLab package (204 files) might take me way
> close to the allowed file limit. I tried to convert the ReportLab
> package into a zip and use zipimport to use it. This causes the
> following error,
>
> AttributeError: 'HardenedModulesHook' object has no attribute '_files'
>
> My source where the imports are called,
> import sys
> sys.path.insert(0, 'ho.zip')
> sys.path.insert(0, 'html5lib.zip')
> sys.path.insert(0, 'sx.zip')
> sys.path.insert(0, 'reportlab.zip')
> import ho.pisa as pisa
>
> Googled a bit for the solution found another mention of this in issue

> tracker,http://code.google.com/p/googleappengine/issues/detail?id=1085.

[Jeff S]

Hello Arun Shanker Prasad,

I'm not familiar with ReportLab, but from reading a tiny bit of their
documentation it seems like they are interested in making their
software usable from within App Engine.

(They mention App Engine on this page http://www.reportlab.org/downloads.html#reportlab
)

Have you tried contacting the ReportLab developers? It looks this the
issue is related to secure runtime restrictions and are triggered by
the module loader during the import. It would be great if this library
worked on App Engine, so I'm hoping that we collectively will figure
this out. I'm not sure if I'll have time to dig in to this issue, as
much as I'd like to.

Thank you,

Jeff

On Apr 6, 10:23 pm, Arun Shanker Prasad <ArunShankerPra...@gmail.com>

[Arun Shanker Prasad]

Thank you Jeff for the help.

I was actually using ReportLab along with Pisa, I had posted a similar
question on their forum as the demo for this (http://www.xhtml2pdf.com/
demo) seems to be hosted in Google App Engine.

I will try the ReportLab developers also and hope they have a
solution.

Meanwhile can I go ahead and upload the libraries to Google App Engine
and convert it to Zip and reduce the number of files later?

Thanks,
Arun Shanker Prasad.

On Apr 8, 2:09 am, Jeff S <j...@google.com> wrote:
> Hello Arun Shanker Prasad,
>
> I'm not familiar with ReportLab, but from reading a tiny bit of their
> documentation it seems like they are interested in making their
> software usable from within App Engine.
>

> (They mention App Engine on this pagehttp://www.reportlab.org/downloads.html#reportlab

[Arun Shanker Prasad]

Hi,

Update: Thanks to the solution from "liping..." (Name not written in
full), I was able to solve the problem with ZipImport and ReportLab.
You can find more details about it from,

Sample hosted in GAE, also contains the source :-
http://ruudhelderman.appspot.com/testpdf
Explanation in issue tracker :- http://code.google.com/p/googleappengine/issues/detail?id=1085

Thanks,
Arun Shanker Prasad.

On Apr 8, 9:21 pm, Arun Shanker Prasad <ArunShankerPra...@gmail.com>

[Arun Shanker Prasad]

Hi,

Spoke too soon. Although this works in the case of importing ReportLab
alone, when used along with Pisa this will fail as the pisa modules
look for the ReportLab package as well and they do not find them from
the zip file.

May need to modify all the pisa packages as well to include,
sys.path.insert(0, 'reportlab.zip')

Thanks,
Arun Shanker Prasad.

On Apr 27, 12:09 pm, Arun Shanker Prasad <ArunShankerPra...@gmail.com>
wrote:
> Hi,
>

> Update: Thanks to the solution from "liping..." (Name not written in
> full), I was able to solve the problem with ZipImport andReportLab.
> You can find more details about it from,
>

> Sample hosted in GAE, also contains the source :-http://ruudhelderman.appspot.com/testpdf

> Explanation in issue tracker :-    http://code.google.com/p/googleappengine/issues/detail?id=1085
>
> Thanks,
> Arun Shanker Prasad.
>
> On Apr 8, 9:21 pm, Arun Shanker Prasad <ArunShankerPra...@gmail.com>
> wrote:
>
> > Thank you Jeff for the help.
>

> > I was actually usingReportLabalong with Pisa, I had posted a similar

> > question on their forum as the demo for this (http://www.xhtml2pdf.com/
> > demo) seems to be hosted in Google App Engine.
>

> > I will try theReportLabdevelopers also and hope they have a

> > solution.
>
> > Meanwhile can I go ahead and upload the libraries to Google App Engine
> > and convert it to Zip and reduce the number of files later?
>
> > Thanks,
> > Arun Shanker Prasad.
>
> > On Apr 8, 2:09 am, Jeff S <j...@google.com> wrote:
>
> > > Hello Arun Shanker Prasad,
>

> > > I'm not familiar withReportLab, but from reading a tiny bit of their

> > > documentation it seems like they are interested in making their
> > > software usable from within App Engine.
>
> > > (They mention App Engine on this pagehttp://www.reportlab.org/downloads.html#reportlab
> > > )
>

> > > Have you tried contacting theReportLabdevelopers? It looks this the

> > > issue is related to secure runtime restrictions and are triggered by
> > > the module loader during the import. It would be great if this library
> > > worked on App Engine, so I'm hoping that we collectively will figure
> > > this out. I'm not sure if I'll have time to dig in to this issue, as
> > > much as I'd like to.
>
> > > Thank you,
>
> > > Jeff
>
> > > On Apr 6, 10:23 pm, Arun Shanker Prasad <ArunShankerPra...@gmail.com>
> > > wrote:
>
> > > > Hi,
>
> > > > Anyone got any work-around for my situation? I am stuck at this
> > > > point...
>
> > > > Thanks,
> > > > Arun Shanker Prasad.
>
> > > > On Apr 6, 5:12 pm, Arun Shanker Prasad <ArunShankerPra...@gmail.com>
> > > > wrote:
>
> > > > > Hi,
>
> > > > > I have a requirement to generate dynamic PDFs from HTML source. I

> > > > > included the Pisa, html5lib and thereportlabpackages for this.

> > > > > Everything works fine in the local environment as long I keep all the
> > > > > packages in the initial source ie I do not zip it.
>

> > > > > Keeping the wholeReportLabpackage (204 files) might take me way

> > > > > close to the allowed file limit. I tried to convert theReportLab
> > > > > package into a zip and use zipimport to use it. This causes the
> > > > > following error,
>
> > > > > AttributeError: 'HardenedModulesHook' object has no attribute '_files'
>
> > > > > My source where the imports are called,
> > > > > import sys
> > > > > sys.path.insert(0, 'ho.zip')
> > > > > sys.path.insert(0, 'html5lib.zip')
> > > > > sys.path.insert(0, 'sx.zip')
> > > > > sys.path.insert(0, 'reportlab.zip')
> > > > > import ho.pisa as pisa
>
> > > > > Googled a bit for the solution found another mention of this in issue
> > > > > tracker,http://code.google.com/p/googleappengine/issues/detail?id=1085.
>
> > > > > Can anyone help me get around this problem? I have seen many use

> > > > >reportlabin Google App Engine how do you guys get around this issue??

[Ruud Helderman]

I patched the ReportLab library, works fine for me.

For a simple demo and full source code, look here:
http://ruudhelderman.appspot.com/testpdf

I added a comment with detailed explanation to issue 1085:
http://code.google.com/p/googleappengine/issues/detail?id=1085

[Arun Shanker Prasad]

Hi Ruud,

Thanks for the patch, I mentioned your patch comment #5. It is great
and works fine when used with the ReportLab package alone.

My problem is that I use ReportLab as a requirement for the Pisa
package,
(http://www.xhtml2pdf.com/doc/pisa-en.html,
http://pypi.python.org/pypi/pisa/)

Since reportlab is called from inside these packages, they are not
able to find the reportlab package. Do you know of any work around for
this?

Thanks,
Arun Shanker Prasad.

[Ruud Helderman]

Hi Arun,
Sorry for my earlier post arriving 'a day after the fair', it got
delayed by moderator policy (check its timestamp).

This is a generic problem - not something specific to either ReportLab
or Pisa. Zipping a library is a matter of choice during deployment -
why should that affect the source code of each module depending on the
library?

In Python documentation, I noticed 2 ways to globally expand sys.path,
without having to adjust individual .py files:
1. PYTHONPATH environment variable
2. .pth files

However, I doubt if either one is available to GAE application
developers. If not, then adjusting the Pisa sources is your only
option, sorry.

IMHO, zipimporter is nice, but immature - I would rather have a more
transparent approach. An API layer on top of the filesystem that hides
the difference between ZIP files and 'real' folders (much like
'compressed folders' in Windows), not only for import statements but
for regular file access as well.


On Apr 28, 6:31 am, Arun Shanker Prasad <ArunShankerPra...@gmail.com>
wrote:

> Hi Ruud,
>
> Thanks for the patch, I mentioned your patch comment #5. It is great
> and works fine when used with the ReportLab package alone.
>
> My problem is that I use ReportLab as a requirement for the Pisa
> package,

> (http://www.xhtml2pdf.com/doc/pisa-en.html,http://pypi.python.org/pypi/pisa/)

[Arun Shanker Prasad]

Hi Ruud,

Thanks for the reply. I did notice the timestamp now :)

I think using the PYTHONPATH and setting .pth is a no go in GAE, as
far as I know..
I was afraid of that, might have to get started in the Pisa code..

Thanks again for the solution, I saw some people using ReportLab in
GAE, will help them a lot.

Thanks,
Arun Shanker Prasad.

> > (http://www.xhtml2pdf.com/doc/pisa-en.html,http://pypi.python.org/pypi...)