installation on debian testing?

[pazz]

I'm, trying to install this package from the master branch (github) on a current debian testing.
There seems to be an issue with the xapian dependency (python3-xapian) which is installed.

$  python3 ./setup.py install --user
...
Installing xapers script to /home/pazz/.local/bin

Installed /home/pazz/.local/lib/python3.6/site-packages/xapers-0.8-py3.6.egg
Processing dependencies for xapers==0.8
Searching for xapian
Reading https://pypi.python.org/simple/xapian/
Couldn't find index page for 'xapian' (maybe misspelled?)
Scanning index of all packages (this may take a while)
Reading https://pypi.python.org/simple/
No local packages or working download links found for xapian
error: Could not find suitable distribution for Requirement.parse('xapian')

I have installed the dependencies according to the README. In particular:

$ python3
Python 3.6.4+ (default, Feb 12 2018, 08:25:03) 
[GCC 7.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import xapian
>>> xapian
<module 'xapian' from '/usr/lib/python3/dist-packages/xapian/__init__.py'>

But:

$ xapers
Traceback (most recent call last):
  File "/home/pazz/.local/bin/xapers", line 6, in <module>
    from pkg_resources import load_entry_point
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 3195, in <module>
    @_call_aside
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 3179, in _call_aside
    f(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 3208, in _initialize_master_working_set
    working_set = WorkingSet._build_master()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 681, in _build_master
    ws.require(__requires__)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 999, in require
    needed = self.resolve(parse_requirements(requirements))
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 885, in resolve
    raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'xapian' distribution was not found and is required by xapers

any ideas?

[jrollins]

Hi, Pazz. First of all, if you're on debian you can actually just install xapers directly:

$ apt policy xapers
xapers:
  Installed: 0.8.2-1
  Candidate: 0.8.2-1
  Version table:
 *** 0.8.2-1 600
        600 https://deb.debian.org/debian testing/main amd64 Packages
        600 https://deb.debian.org/debian testing/main i386 Packages
        200 https://deb.debian.org/debian unstable/main amd64 Packages
        200 https://deb.debian.org/debian unstable/main i386 Packages
        100 /var/lib/dpkg/status
     0.7.1-1 500
        500 https://deb.debian.org/debian stable/main amd64 Packages
        500 https://deb.debian.org/debian stable/main i386 Packages

I maintain the debian packaging, so it's always up-to-date, and automatically pulls in all needed dependencies (including python3-xapian).

The xapian python bindings wrap the underlying C++ interface to xapian. It looks like they're not available in pip. But again, if you're on debian, you should just be able to install the python3-xapian package to pull in the dependency.

[jrollins]

Should also mention that the github repo was a bit out of date and I've updated it with the latest release.

[jrollins]

And to finally address your question, I have no idea why you're not finding xapian at runtime. I assume it has to do with your environment when running from those local installs. It seems to be not finding system-installed packages? I don't ever run python packages from local installs like that, so I'm not sure what to suggest. Make sure your PYTHONPATH is set properly?

xapers from the debian packaging certainly works though...

[pazz]

hi @jrollins thanks for the quick reply.
I was hoping to get a development version running and ultimately perhaps to land my ages-old patches that rewrite the parsers-code (to include postscript etc).
How do you develop then? Do you keep re-installing a system-wide installation?

[pazz]

By the way: I get exactly the same problem (install tries and fails to download xapian from pip) when I try to do a system-wide install via

sudo python3 ./setup.py install

[pazz]

I should say that python3-xapian is installed of course (the import works as expected).

[jrollins]

That would be great!

When testing I always just run right out of the source working directory:

servo:~/src/xapers/git [master] 141$ PYTHONPATH=lib python3 -m xapers --version
xapers 0.8.2
servo:~/src/xapers/git [master] 0$ 

I guess you're running into intricacies in how debian handles python packages. Is setup.py installing in site-packages instead of dist-packages?

[pazz]

Is setup.py installing in site-packages instead of dist-packages?
yes, I think so?

But this does not explain why python3 setup.py ultimately seems to fail to find the xapian lib, whereas python3 does not.

I'm also really confused about the PYTHONPATH behaviour:

$ PYTHONPATH=lib python3 -m xapers --version

works as expexted (as you do, in the xapers checkout). BUT:

PYTHONPATH=lib xapers --version 
Traceback (most recent call last): 
  File "/usr/local/bin/xapers", line 6, in <module>
    from pkg_resources import load_entry_point
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 3195, in <module>
    @_call_aside
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 3179, in _call_aside
    f(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 3208, in _initialize_master_working_set
    working_set = WorkingSet._build_master()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 681, in _build_master
    ws.require(__requires__)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 999, in require
    needed = self.resolve(parse_requirements(requirements))
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 885, in resolve
    raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'xapian' distribution was not found and is required by xapers

I tried replacing the first line of /usr/local/bin/xapers from

#!/usr/bin/python3

to

#!/usr/bin/env python3

but this makes no difference.

[pazz]

Why does the system-wide version from the debian package work at all?!? It should fail for exactly the same reasons