"""Run a module as if it were a file
Allows Python scripts to be located and run using the Python module namespace
instead of the native filesystem.
"""
from imp import find_module, PY_SOURCE, PY_COMPILED
import sys
__all__ = ['execmodule']
class _ExecError(ValueError): pass
def execmodule(module_name, globals=None, locals=None, set_argv0 = False):
"""Locate the requested module and run it using execfile
Any containing packages will be imported before the module is executed.
Globals and locals arguments are as documented for execfile
set_argv0 means that sys.argv[0] will be set to the module's filename prior
to execution (some scripts use argv[0] to determine their location).
"""
if globals is None:
globals = sys._getframe(1).f_globals # Mimic execfile behaviour
if locals is None:
locals = globals
pkg_name = None
path = None
split_module = module_name.rsplit('.', 1)
if len(split_module) == 2:
module_name = split_module[1]
pkg_name = split_module[0]
try:
# Import the containing package
if pkg_name:
pkg = __import__(pkg_name)
for sub_pkg in pkg_name.split('.')[1:]:
pkg = getattr(pkg, sub_pkg)
path = pkg.__path__
# Locate the module
module_info = find_module(module_name, path)
except ImportError, e:
raise _ExecError(str(e))
# Check that all is good
module = module_info[0]
filename = module_info[1]
filetype = module_info[2][2]
if module: module.close() # We don't actually want the file handle
if filetype not in (PY_SOURCE, PY_COMPILED):
raise _ExecError("%s is not usable as a script\n (File: %s)" %
(module_name, filename))
# Let's do it
if set_argv0:
sys.argv[0] = filename
execfile(filename, globals, locals)
if __name__ == "__main__":
if len(sys.argv) < 2:
print >> sys.stderr, "No module specified for execution"
del sys.argv[0] # Make the requested module sys.argv[0]
try:
execmodule(sys.argv[0], set_argv0 = True)
except _ExecError, e:
print >> sys.stderr, e
