parse version number from package init, avoid package import

letsencrypt/__init__.py

@@ -1,10 +1,3 @@
 """Let's Encrypt."""
 
-# do not import stuff here. this file is used by setup.py, thus importing
-# stuff here might break setup.py as dependencies are not installed yet.
-
-VERSION_TUPLE = 0, 1, 0, "a0"
-"""version tuple: major, minor, micro, {a|b|rc}N - see PEP440"""
-
-VERSION = "%d.%d.%d%s" % VERSION_TUPLE
-"""version as str"""
+__version__ = "0.1"

letsencrypt/scripts/main.py

@@ -8,7 +8,7 @@ import sys
 import zope.component
 import zope.interface
 
-from letsencrypt import VERSION
+import letsencrypt
 from letsencrypt.client import CONFIG
 from letsencrypt.client import client
 from letsencrypt.client import display
@@ -20,7 +20,7 @@ from letsencrypt.client import log
 def main():  # pylint: disable=too-many-statements,too-many-branches
     """Command line argument parsing and main script execution."""
     parser = argparse.ArgumentParser(
-        description="letsencrypt client %s" % VERSION)
+        description="letsencrypt client %s" % letsencrypt.__version__)
 
     parser.add_argument("-d", "--domains", dest="domains", metavar="DOMAIN",
                         nargs="+")

setup.py

@@ -1,7 +1,17 @@
 #!/usr/bin/env python
+import os
+import re
+import codecs
+
 from setuptools import setup
 
-from letsencrypt import VERSION
+here = os.path.abspath(os.path.dirname(__file__))
+
+# read version number (and other metadata) from package init
+init_fn = os.path.join(here, 'letsencrypt', '__init__.py')
+with codecs.open(init_fn, encoding='utf8') as meta_file:
+    content = meta_file.read()
+meta = dict(re.findall(r"""__([a-z]+)__ = "([^"]+)""", content))
 
 install_requires = [
     'argparse',
@@ -32,7 +42,7 @@ testing_extras = [
 
 setup(
     name="letsencrypt",
-    version=VERSION,
+    version=meta['version'],
     description="Let's Encrypt",
     author="Let's Encrypt Project",
     license="",