refactor versioning scheme

the central versioning file is now _postpic_version.py. It will be
called by setup.py as well as by postpic itself.

_postpic_version.py will try to retrieve the version info from git
first. If that fails it will try to access a version fiel _version.txt,
which will be written, whenever getting the version from git succeds.

.gitignore

+# auto generated by setup.py
+_version.txt
+
 examples/_openPMDdata
 
 # Byte-compiled / optimized / DLL files

MANIFEST.in

@@ -2,3 +2,5 @@ include *.md
 include LICENSE
 include CONTRIBUTING.md
 include postpic/*.pyx
+include _version.txt
+include postpic/_version.txt

_postpic_version.py

+postpic/_postpic_version.py
\ No newline at end of file

postpic/__init__.py

@@ -32,6 +32,7 @@ from .particles import *
 from . import datareader
 from .datareader import chooseCode, readDump, readSim
 from . import plotting
+from . import _postpic_version
 
 __all__ = ['helper']
 __all__ += datahandling.__all__
@@ -42,36 +43,5 @@ __all__ += ['datareader', 'plotting']
 __all__ += ['chooseCode', 'readDump', 'readSim']
 
 
-def _createversionstring():
-    from pkg_resources import get_distribution, DistributionNotFound
-    # read version from installed metadata
-    try:
-        import os.path
-        _dist = get_distribution('postpic')
-        # Normalize case for Windows systems
-        dist_loc = os.path.normcase(_dist.location)
-        here = os.path.normcase(__file__)
-        if not here.startswith(os.path.join(dist_loc, 'postpic')):
-            # not installed, but there is another version that *is*
-            raise DistributionNotFound
-    except DistributionNotFound:
-        __version__ = 'Please install this project with setup.py'
-    else:
-        __version__ = _dist.version
+__git_version__, __version__ = _postpic_version.getversion_package()
 
-    # add Git description for __version__ if present
-    try:
-        import subprocess as sub
-        import os.path
-        cwd = os.path.dirname(__file__)
-        p = sub.Popen(['git', 'describe', '--always', '--dirty'], stdout=sub.PIPE,
-                      stderr=sub.PIPE, cwd=cwd)
-        out, err = p.communicate()
-        if not p.returncode:  # git exited without error
-            __version__ += '_' + str(out)
-    except OSError:
-        # 'git' command not found
-        pass
-    return __version__
-
-__version__ = _createversionstring()

postpic/_postpic_version.py

+#!/usr/bin/env python
+
+# Copyright (C) 2016 Stephan Kuschel
+#
+# This file is part of postpic.
+#
+# postpic is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# postpic is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with postpic. If not, see <http://www.gnu.org/licenses/>.
+#
+
+
+from __future__ import absolute_import, division, print_function, unicode_literals
+
+
+__version__ = 'v0.2.2'
+
+
+def _gitversion():
+    '''
+    returns the git version string if the source in inside a git repo.
+    returns None otherwise.
+    '''
+    ret = None
+    try:
+        import subprocess as sub
+        import os.path
+        cwd = os.path.dirname(__file__)
+        p = sub.Popen(['git', 'describe', '--always', '--long', '--dirty'], stdout=sub.PIPE,
+                      stderr=sub.PIPE, cwd=cwd)
+        out, err = p.communicate()
+        if not p.returncode:  # git ran without error
+            ret = out.decode().strip('\n')
+    except OSError:
+        # 'git' command not found
+        pass
+    return ret
+
+
+def _version(gitversion):
+    '''
+    returns the version as readable for setup.py.
+    For example: v0.2.2, v0.1.7-65
+    '''
+    ret = gitversion.strip('-dirty')
+    ret = ret[:-9]  # remove the SHA
+    ret = ret.strip('-0')
+    return ret
+
+
+def getversion_setup():
+    # search for the current version with git
+    gitversion = _gitversion()
+    # if found, write it to _version.txt and postpic/_version.txt
+    if gitversion is not None:
+        version = _version(gitversion)
+        with open('_version.txt', 'w') as fs, open('postpic/_version.txt', 'w') as fp:
+            for f in [fs, fp]:
+                f.write(gitversion + '\n')
+                f.write(version + '\n')
+    # if not found, try to read from _version.txt
+    else:
+        try:
+            with open('_version.txt', 'r') as f:
+                gitversion = f.readline()
+                version = f.readline()
+        except(FileNotFoundError):
+            # this can happen, if the code is downloaded
+            # from github directly as zip or tar
+            version = __version__
+            gitversion = 'unknown'
+    return gitversion, version
+
+
+def getversion_package():
+    # search for the current version with git
+    gitversion = _gitversion()
+    # if found, write it to _version.txt and postpic/_version.txt
+    if gitversion is not None:
+        version = _version(gitversion)
+    # if not found, try to read from _version.txt
+    else:
+        try:
+            import pkgutil
+            data = pkgutil.get_data('postpic', '_version.txt')
+            gitversion, version = data.decode().splitlines()
+        except(FileNotFoundError):
+            # this can happen, if the code is downloaded
+            # from github directly as zip or tar
+            version = __version__
+            gitversion = 'unknown'
+    return gitversion, version
+
+

setup.py

 #!/usr/bin/env python
+
+# Copyright (C) 2016 Stephan Kuschel
 #
 # This file is part of postpic.
 #
@@ -18,9 +20,16 @@
 from setuptools import setup, find_packages
 from Cython.Build import cythonize
 import numpy
+import os
+
+
+import _postpic_version
+_, version = _postpic_version.getversion_setup()
+
 
 setup(name='postpic',
-      version='0.2.2',
+      version=version,
+      include_package_data = True,
       author='Stephan Kuschel',
       author_email='stephan.kuschel@gmail.de',
       description='The open source particle-in-cell post processor.',