infer version from git-describe

dspawn/__init__.py

@@ -8,5 +8,3 @@ systemd-networkd)
 
 Example usage: dspawn create bar.foo; ssh roo@bar.foo
 """
-
-__version__ = '0.11'

setup.py

@@ -1,8 +1,35 @@
 from setuptools import setup
 import dspawn
 
+
+def get_version():
+    '''Use the VERSION, if absent generates a version with git describe, if not
+       tag exists, take 0.0- and add the length of the commit log.
+    '''
+    if os.path.exists('VERSION'):
+        with open('VERSION', 'r') as v:
+            return v.read()
+    if os.path.exists('.git'):
+        p = subprocess.Popen(['git','describe','--dirty=.dirty','--match=v*'],
+                stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        result = p.communicate()[0]
+        if p.returncode == 0:
+            result = result.decode('ascii').strip()[1:]  # strip spaces/newlines and initial v
+            if '-' in result:  # not a tagged version
+                real_number, commit_count, commit_hash = result.split('-', 2)
+                version = '%s.post%s+%s' % (real_number, commit_count, commit_hash)
+            else:
+                version = result
+            return version
+        else:
+            return '0.0.post%s' % len(
+                    subprocess.check_output(
+                            ['git', 'rev-list', 'HEAD']).splitlines())
+    return '0.0'
+
+
 setup(name='dspawn',
-      version=dspawn.__version__,
+      version=get_version(),
       description='systemd-nspawn container manager',
       author='Christophe Siraut',
       author_email='csiraut@entrouvert.com',