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

pbr/hooks/commands.py

@@ -42,6 +42,7 @@ class CommandsConfig(base.BaseConfig):
         self.add_command('pbr.packaging.LocalSDist')
         self.add_command('pbr.packaging.LocalInstallScripts')
         self.add_command('pbr.packaging.LocalDevelop')
+        self.add_command('pbr.packaging.LocalRPMVersion')
         if os.name != 'nt':
             easy_install.get_script_args = packaging.override_get_script_args
 

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
 

pbr/tests/test_commands.py

@@ -56,3 +56,11 @@ class TestCommands(base.BaseTestCase):
         self.addDetail('stderr', content.text_content(stderr))
         self.assertIn('Running custom build_py command.', stdout)
         self.assertEqual(return_code, 0)
+
+    def test_custom_rpm_version_py_command(self):
+        """Test custom rpm_version command."""
+        stdout, stderr, return_code = self.run_setup('rpm_version')
+        self.addDetail('stdout', content.text_content(stdout))
+        self.addDetail('stderr', content.text_content(stderr))
+        self.assertIn('Extracting rpm version', stdout)
+        self.assertEqual(return_code, 0)