rpm spec file skeleton to real spec file - variables

Question

The aim is to have skeleton spec fun.spec.skel file which contains placeholders for Version, Release and that kind of things.
For the sake of simplicity I try to make a build target which updates those variables such that I transform the fun.spec.skel to fun.spec which I can then commit in my github repo. This is done such that rpmbuild -ta fun.tar does work nicely and no manual modifications of fun.spec.skel are required (people tend to forget to bump the version in the spec file, but not in the buildsystem).

Answer 1

Assuming the implied question is "How would I do this?", the common answer is to put placeholders in the file like ##VERSION## and then sed the file, or get more complicated and have autotools do it.

Answer 2

We place a version.mk file in our project directories which define environment variables. Sample content includes:
RELPKG=foopackage
RELFULLVERS=1.0.0
As part of a script which builds the RPM, we can source this file:
#!/bin/bash
. $(pwd)/Version.mk
export RELPKG RELFULLVERS
if [ -z "${RELPKG}" ]; then exit 1; fi
if [ -z "${RELFULLVERS}" ]; then exit 1; fi
This leaves us a couple of options to access the values which were set:
We can define macros on the rpmbuild command line:
% rpmbuild -ba --define "relpkg ${RELPKG}" --define "relfullvers ${RELFULLVERS}" foopackage.spec
We can access the environment variables using %{getenv:...} in the spec file itself (though this can be harder to deal with errors...):
%define relpkg %{getenv:RELPKG}
%define relfullvers %{getenv:RELFULLVERS}
From here, you simply use the macros in your spec file:
Name: %{relpkg}
Version: %{relfullvers}
We have similar values (provided by environment variables enabled through Jenkins) which provide the build number which plugs into the "Release" tag.

Answer 3

I found two ways:
a) use something like
Version: %(./waf version)
where version is a custom waf target
def version_fun(ctx):
print(VERSION)
class version(Context):
"""Printout the version and only the version"""
cmd = 'version'
fun = 'version_fun'
this checks the version at rpm build time
b) create a target that modifies the specfile itself
from waflib.Context import Context
import re
def bumprpmver_fun(ctx):
spec = ctx.path.find_node('oregano.spec')
data = None
with open(spec.abspath()) as f:
data = f.read()
if data:
data = (re.sub(r'^(\s*Version\s*:\s*)[\w.]+\s*', r'\1 {0}\n'.format(VERSION), data, flags=re.MULTILINE))
with open(spec.abspath(),'w') as f:
f.write(data)
else:
logs.warn("Didn't find that spec file: '{0}'".format(spec.abspath()))
class bumprpmver(Context):
"""Bump version"""
cmd = 'bumprpmver'
fun = 'bumprpmver_fun'
The latter is used in my pet project oregano # github