Generate salt._version when installing so we can have the git describe information. Fixes #2587.

setup.py

@@ -8,8 +8,11 @@ from __future__ import with_statement
 
 import os
 import sys
+from datetime import datetime
 from distutils.cmd import Command
+from distutils.command.build import build
 from distutils.command.clean import clean
+from distutils.command.install import install
 from distutils.sysconfig import get_python_lib, PREFIX
 
 # Change to salt source's directory prior to running any command
@@ -109,6 +112,43 @@ class Clean(clean):
                             break
 
 
+install_version_template = """\
+# This file was auto-generated by salt's setup on \
+{date:%A, %d %B %Y @ %H:%m:%S UTC}'.
+
+__version__ = {version!r}
+__version_info__ = {version_info!r}
+"""
+
+
+class Build(build):
+    def run(self):
+        # Run build.run function
+        build.run(self)
+        # If our install attribute is present and set to True, we'll go ahead
+        # and write our install time _version.py file.
+        if getattr(self.distribution, 'running_salt_install', False):
+            version_file_path = os.path.join(
+                self.build_lib, 'salt', '_version.py'
+            )
+            open(version_file_path, 'w').write(
+                install_version_template.format(
+                    date=datetime.utcnow(),
+                    version=__version__,
+                    version_info=__version_info__
+                )
+            )
+
+
+class Install(install):
+    def run(self):
+        # Let's set the running_salt_install attribute so we can add
+        # _version.py in the build command
+        self.distribution.running_salt_install = True
+        # Run install.run
+        install.run(self)
+
+
 NAME = 'salt'
 VER = __version__
 DESC = ('Portable, distributed, remote execution and '
@@ -134,7 +174,12 @@ setup_kwargs = {'name': NAME,
                 'author': 'Thomas S Hatch',
                 'author_email': 'thatch45@gmail.com',
                 'url': 'http://saltstack.org',
-                'cmdclass': {'test': TestCommand, 'clean': Clean},
+                'cmdclass': {
+                    'test': TestCommand,
+                    'clean': Clean,
+                    'build': Build,
+                    'install': Install
+                },
                 'classifiers': ['Programming Language :: Python',
                                 'Programming Language :: Cython',
                                 'Programming Language :: Python :: 2.6',