Check the Python version on install

[hm2k]

[root@vps112 ~]# trac-admin
Traceback (most recent call last):
  File "/usr/bin/trac-admin", line 7, in ?
    sys.exit(
  File "/usr/lib/python2.3/site-packages/setuptools-0.6c11-py2.3.egg/pkg_resources.py", line 318, in load_entry_point
    return get_distribution(dist).load_entry_point(group, name)
  File "/usr/lib/python2.3/site-packages/setuptools-0.6c11-py2.3.egg/pkg_resources.py", line 2221, in load_entry_point
    return ep.load()
  File "/usr/lib/python2.3/site-packages/setuptools-0.6c11-py2.3.egg/pkg_resources.py", line 1954, in load
    entry = __import__(self.module_name, globals(),globals(), ['__name__'])
  File "build/bdist.linux-i686/egg/trac/admin/__init__.py", line 14, in ?
  File "/usr/lib/python2.3/site-packages/Trac-0.13dev_r10030-py2.3.egg/trac/admin/api.py", line 140
    return list(set(a for a in self if a.startswith(text)))
                        ^
SyntaxError: invalid syntax

[Christian Boos]

You're using Python 2.3, which is not supported anymore starting with Trac 0.12.

And with Trac 0.13dev, you'll even need Python 2.5.

See TracInstall and 0.13/TracInstall.

[hm2k]

You mean there's no testing to check for the required version?

That seems silly to me.

[Remy Blank]

Replying to hm2k:

You mean there's no testing to check for the required version?

You have a point there. We should probably add a check to setup.py.

[hm2k]

Yes, a check would be useful. I'd hope this has been implemented by now.

With regards to this, I decided the only thing to do was to upgrade the system from CentOS 4 to CentOS 5, only to find that Python is only 2.4:

[root@vps112 ~]# rpm -q python
python-2.4.3-27.el5_5.3

The reason for this is probably due to backporting: ​http://tinyurl.com/r77l2

It's official: I'm unable to setup/install Trac on CentOS. Am I overlooking something here?

Can anyone advise further?

[Remy Blank]

Install 0.12.1 or from the 0.12-stable branch, which support Python 2.4.

I'll add the version check.

[Remy Blank]

Version check added in [10364].

[Peter Suter]

​Apparently this still raises a syntax error in Python 3:

File "c:... \setuptools-0.9.8-py3.3.egg\setuptools\sandbox.py", line 71 in <lambda>
File "c:... \setuptools-0.9.8-py3.3.egg\setuptoools\compat.p", line 92 in execfile
File "setup.py", line 21  print "Trac requires Python %d.%d or later" % min_python
SyntaxError: invalid syntax

Adding parentheses to all three print statements in that file​ might make the file "Python 3 compatible enough" to print the nicer error message. (I have not yet confirmed this though.)

[Ryan J Ollos]

I tested out your suggestion, and Trac doesn't support Python 3 (yet) is printed after adding parenthesis to all 3 print statements in setup.py. Tested with Python 3.3.1, 1.0-stable on Ubuntu 13.04.

setup.py

@@ -18 +18 @@
 
 min_python = (2, 5)
 if sys.version_info < min_python:
-    print "Trac requires Python %d.%d or later" % min_python
+    print("Trac requires Python %d.%d or later" % min_python)
     sys.exit(1)
 if sys.version_info >= (3,):
-    print "Trac doesn't support Python 3 (yet)"
+    print("Trac doesn't support Python 3 (yet)")
     sys.exit(1)
 
 extra = {}
@@ -49 +49 @@
 try:
     import genshi
 except ImportError:
-    print "Genshi is needed by Trac setup, pre-installing"
+    print("Genshi is needed by Trac setup, pre-installing")
     # give some context to the warnings we might get when installing Genshi

Let me know if that looks good to you and I'm happy to push the change.

[Peter Suter]

Thanks for testing! Looks good to me.

[Peter Suter]

(For reference: #10083 is about real Python 3 support.)

[Ryan J Ollos]

Assuming you meant to add this to Keywords, and I find myself putting keywords in the Cc field fairly often. I see other people on my dev team do it as well, so it might be something we want to address eventually.

[Peter Suter]

Oops, yes. Thanks for fixing. (Apparently I'm more used to a different number and distribution of fields.)

[Ryan J Ollos]

Also tested with 1.0-stable and Python 2.5, 2.6 and 2.7; 0.12-stable and Python 2.4 (on Ubuntu 13.04).

Committed to 0.12-stable in [11936], merged to 1.0-stable in [11937] and merged to trunk in [11938]. Thanks Peter!