How can I get SCons to replace text in installed text files

Question

I'd like to be able to replace a template variable ('$(SOFTWARE_VERSION)') while installing some python scripts from scons. Does scons already have such functionality? If not, what's the best way to hook into the scons install process so I can do this during install?

Answer 1

You could use the Substfile method. This takes a input file and produces an output file substituting marked variables. So if you have script.py.in:

#!/usr/bin/python
print "$SOFTWARE_VERSION"

Then you can use the following SConsctruct file to generate an output:

env = Environment(tools=['textfile'])
script_dict = {'\$SOFTWARE_VERSION': '1.0'}
env.Substfile('script.py.in', SUBST_DICT = script_dict)

You need to escape the $ in the string '\$SOFTWARE_VERSION' otherwise SCons interprets it as an internal environment variable. The result would be a file script.py with this contents:

#!/usr/bin/python
print "1.0"

You can then install this resulting substituted file using env.Install.