- Added TODO item of dry_run mode.

- Starting work on command arguments.

README.rst

@@ -10,4 +10,4 @@ TODO
 - Changelog.
 - README,
 - Testing with different Python versions with tox and flake8.
-- Specify number of versions to keep.
+- Specify number of versions to keep, dry-run option.

eb_prune/__init__.py

@@ -6,6 +6,8 @@ from botocore import session
 
 
 def main():
+    versions_to_keep = 400
+    dry_run = False
     print('Pruning Elastic Beanstalk versions.')
     aws_session = session.get_session()
     beanstalk_client = aws_session.create_client('elasticbeanstalk')
@@ -21,8 +23,10 @@ def main():
         lambda x: (not x['VersionLabel'] in active_versions) and
         x['Status'] == 'UNPROCESSED', versions)
     old_versions = sorted(previous_versions,
-                          key=lambda x: x.get('DateCreated'))[:-400]
+                          key=lambda x:
+                          x.get('DateCreated'))[:-versions_to_keep]
     for version in old_versions:
+        if not dry_run:
             response = beanstalk_client.delete_application_version(
                 ApplicationName=version['ApplicationName'],
                 VersionLabel=version['VersionLabel'],