Spyne in Google App Engine.

[neriksso]

Recently I had to include SOAP service within Django app that was running in Google App Engine. There aren't many good SOAP libraries for python and even fewer work within the GAE sandbox. Spyne seems to be the best library out there, so I decided to try to modify it to work inside the GAE sandbox. Fortunately, it didn't require too many changes to the library.

Python module mmap is not supported inside GAE, therefore added a catch for the ImportError and an assert upon mmap usage.
Also, refactored build_validation_schema to use memcache and StringIO when tempfile.mkdtemp raises NotImplementedError.
(In GAE, tempfile.TemporaryFile is an alias for StringIO)

Tested with helloworld soap example with normal WSGI app and Django.

[landscape-bot]

Repository health increased by 0.01% when pulling 7aad1d2 on neriksso:feature/gae into 6e7ac77 on arskom:master.

• 2 new problems were found (including 0 errors and 2 code smells).
• 2 problems were fixed (including 0 errors and 2 code smells).

[plq]

Interesting, thanks for the patch.

You don't need a plan b for when mmap is missing? Large requests need mmap for some transports.

[neriksso]

You probably do need a plan b for those cases, hence I added the asserts to inform when that occurs. Would probably need to build some sort of replacement with StringIO perhaps? GAE needs pure python libraries and therefore mmap is not available in its sandbox..

[plq]

GAE needs pure python libraries and therefore mmap is not available in its sandbox..

I thought mmap was part of stdlib?

[neriksso]

Yes, it is part of the stdlib but it is disabled in GAE, sorry for the confusion. I was trying to say that you can't include it manually as it is a c extension, if I'm not terribly mistaken?

All code for the Python runtime environment must be pure Python, and not include any C extensions or other code that must be compiled.

The environment includes the Python standard library. Some modules have been disabled because their core functions are not supported by App Engine, such as networking or writing to the filesystem. In addition, the os module is available, but with unsupported features disabled. An attempt to import an unsupported module or use an unsupported feature will raise an exception.

A few modules from the standard library have been replaced or customized to work with App Engine. These modules vary between the two Python runtimes, as described below.

I don't know the specifics of the mmap module but I would guess it is using the file system which is why it is disabled.

[landscape-bot]

Repository health decreased by 0.53% when pulling 7aad1d2 on neriksso:feature/gae into b35f6c2 on arskom:master.

• 217 new problems were found (including 4 errors and 166 code smells).
• 271 problems were fixed (including 5 errors and 192 code smells).