Find Out Python Version From Source Code (or Heroku)

We run a site called inteokej.nu and I need to find out which version of Python it runs on. I have pulled all the files to my computer but I don't know if and how I can find out th

Solution 1:

Depending on what you need. Either (a) the version you are running on or (b) the version under the .pyc file was compiled?

a. If you need to know the python version you are running, do the following:

>>> import sys
>>> sys.version_info
sys.version_info(major=2, minor=7, micro=3, releaselevel='final', serial=0)
>>> print sys.version_info.major
2>>> print sys.version_info.minor
7>>> print sys.version_info.micro
3>>> print'%s.%s.%s' % (sys.version_info.major, sys.version_info.minor, sys.version_info.micro)
2.7.3

b. If you want to know the python version under a .pyc file was compiled, do the following:

>>>f = open('somefile.pyc')>>>magic = f.read(4)>>>magic
'\x03\xf3\r\n'
>>>magic.encode('hex')
'03f30d0a'
>>>import struct>>>struct.unpack("<HH", magic)
(62211, 2573)
>>>struct.unpack("<HH", magic)[0]
62211

The known values are listed in the python source file Python/import.c. Here the known values from Python 2.7.10rc1:

Python 1.5:20121Python 1.5.1:20121Python 1.5.2:20121Python 1.6:50428Python 2.0:50823Python 2.0.1:50823Python 2.1:60202Python 2.1.1:60202Python 2.1.2:60202Python 2.2:60717Python 2.3a0:62011Python 2.3a0:62021Python 2.3a0:62011(!)Python 2.4a0:62041Python 2.4a3:62051Python 2.4b1:62061Python 2.5a0:62071Python 2.5a0:62081(ast-branch)Python 2.5a0:62091(with)Python 2.5a0:62092(changedWITH_CLEANUPopcode)Python 2.5b3:62101(fixwrong code:forx,in...)Python 2.5b3:62111(fixwrong code:x+=yield)Python 2.5c1:62121(fixwronglnotabwithforloopsandstoringconstantsthatshouldhavebeenremoved)Python 2.5c2:62131(fixwrong code:forx,in...inlistcomp/genexp)Python 2.6a0:62151(peepholeoptimizationsandSTORE_MAPopcode)Python 2.6a1:62161(WITH_CLEANUPoptimization)Python 2.7a0:62171(optimizelistcomprehensions/changeLIST_APPEND)Python 2.7a0:62181(optimizeconditional branches:introducePOP_JUMP_IF_FALSEandPOP_JUMP_IF_TRUE)Python2.7a062191(introduceSETUP_WITH)Python2.7a062201(introduceBUILD_SET)Python2.7a062211(introduceMAP_ADDandSET_ADD)

To solve your problem, you could recursively walk your directory and extract the values from every .pyc file and populate a dictionary with a list of files for every value/version. See following example:

import os, struct

your_path = '/your/path'# <- enter your path here
values = {}

for root, dirs, files in os.walk(your_path):
    for file in files:
        if file.endswith('.pyc'):
            full_path = os.path.join(root, file)
            value = struct.unpack("<HH", open(full_path).read(4))[0] # <- evtl. enclose this in a try blockifnot values.has_key(value):
                values[value] = []
            values[value].append(full_path)
            print'%s %s' % (value, full_path)

for value, files in values.items():
    print'Following files have value %s' % (value)
    for file in files:
        print'    %s' % (file)

If you are under Linux, you could solve your problem with the following one line commando (thanks to Neftas suggestion!):

dir=/your/path; find ${dir} -name "*.pyc" | whileread file; dohead -c 2 ${file} | od -d | head -n 1 | awk -v z=${file} -F ' ''{print $2 "\t" z}'; done

This outputs a list with value and filename like the following:

62211   /usr/lib/pymodules/python2.7/reportbug/ui/urwid_ui.pyc
62211   /usr/lib/pymodules/python2.7/reportbug/debbugs.pyc
62211   /usr/lib/pymodules/python2.7/reportbug/checkbuildd.pyc
...
62161   /usr/lib/pymodules/python2.6/debianbts.pyc
62161   /usr/lib/pymodules/python2.6/fpconst.pyc
62161   /usr/lib/pymodules/python2.6/SOAPpy/Server.pyc
...

Solution 2:

Seems like the least complex answer (for Heroku) is missing:

Log into Heroku bash session, something like this in your authenticated terminal:

heroku run bash --app YOURAPPNAME

then type:

python --version

done

Solution 3:

You want to know what runtime is used to run your code on Heroku. At the time of writing this, new applications default to the Python 2.7.9 runtime. This may have been modified in the 'runtime.txt' file so to find out if it has been set:

$ cat runtime.txt
python-3.4.2

Solution 4:

If you didn't have access to source code, from headers I can see that server is using Gunicorn 0.17.2, which is compatible with Python 2.x >= 2.6, which rules out i.e. Python 3.