Expose a 'rpm_version' extra command

Intended usage, getting a rpm *compatible* version number from pbr
from a pbr using python package. Typically this will then get
put into a rpm spec file (what is used to build an rpm) and used to
build an rpm using `rpmbuild` (the thing used to translate rpm spec
files into rpms).

For example: this allows [1][2] (which I am the primary maintainer of
and godaddy, cray, and y! are users of) to get out of the whacky
and/or flakey rpm version number calculation/conversion process (which
previously just worked around by saying only use tags).

[1] https://github.com/stackforge/anvil
[2] https://anvil.readthedocs.org/en/latest/topics/summary.html

Change-Id: I26cd1d6e8aef69d52e8a4f36bd264c690e712ba3

1 files changed, 20 insertions, 0 deletions

diff --git a/pbr/packaging.py b/pbr/packaging.py
index ebdfb09..3ab930f 100644
--- a/pbr/packaging.py
+++ b/pbr/packaging.py
@@ -28,6 +28,7 @@ import re
 import sys
 
 import pkg_resources
+import setuptools
 from setuptools.command import develop
 from setuptools.command import easy_install
 from setuptools.command import egg_info
@@ -187,6 +188,25 @@ class TestrTest(testr_command.Testr):
         testr_command.Testr.run(self)
 
 
+class LocalRPMVersion(setuptools.Command):
+    __doc__ = """Output the rpm *compatible* version string of this package"""
+    description = __doc__
+
+    user_options = []
+    command_name = "rpm_version"
+
+    def run(self):
+        log.info("[pbr] Extracting rpm version")
+        name = self.distribution.get_name()
+        print(version.VersionInfo(name).semantic_version().rpm_string())
+
+    def initialize_options(self):
+        pass
+
+    def finalize_options(self):
+        pass
+
+
 def have_testr():
     return testr_command.have_testr