Fixed lambda-uploader to work with Python 3, using tox for testing

This change adds the ability to run lambda-uploader in a local Python 3
environment. The lambda-uploader will explicitly look for a python2
executable instead of just using python.

Author: jarosser06

Diff for: circle.yml

@@ -1,15 +1,13 @@
-dependencies:
-  pre:
-    - rm -r ~/virtualenvs
-
 machine:
   python:
-    version: 2.7
+    version: '2.7.10'
+
+dependencies:
+  override:
+    - pip install -U pip
+    - pip install -U tox tox-pyenv
+    - pyenv local 2.7.9 3.4.3 3.5.0
 
 test:
-  pre:
-    - pip install -r test-requirements.txt
-    - python setup.py develop
   override:
-    - flake8 .
-    - py.test
+    - tox

Diff for: lambda_uploader/config.py

@@ -15,6 +15,12 @@
 import json
 from os import path
 
+# Python 2/3 compatability
+try:
+    basestring
+except NameError:
+    basestring = str
+
 REQUIRED_PARAMS = {u'name': basestring, u'description': basestring,
                    u'region': basestring, u'handler': basestring,
                    u'role': basestring, u'timeout': int, u'memory': int}
@@ -37,7 +43,7 @@ def __init__(self, pth, config_file=None, role=None):
         if self._config['vpc']:
             self._validate_vpc()
 
-        for param, clss in REQUIRED_PARAMS.iteritems():
+        for param, clss in REQUIRED_PARAMS.items():
             self._validate(param, cls=clss)
 
     '''
@@ -81,7 +87,7 @@ def set_alias(self, alias, description=None):
 
     '''Set all defaults after loading the config'''
     def _set_defaults(self):
-        for param, val in DEFAULT_PARAMS.iteritems():
+        for param, val in DEFAULT_PARAMS.items():
             if self._config.get(param) is None:
                 self._config[param] = val
 
@@ -95,7 +101,7 @@ def _validate(self, key, cls=None):
 
     '''Validate the VPC configuration'''
     def _validate_vpc(self):
-        for param, clss in REQUIRED_VPC_PARAMS.iteritems():
+        for param, clss in REQUIRED_VPC_PARAMS.items():
             self._compare(param, clss, self._config['vpc'].get(param))
 
             if len(self._config['vpc'].get(param)) == 0:

Diff for: lambda_uploader/package.py

@@ -20,6 +20,7 @@
 
 from subprocess import Popen, PIPE
 from lambda_uploader import utils
+from distutils.spawn import find_executable
 
 # Python 2/3 compatability
 try:
@@ -160,8 +161,8 @@ def _build_new_virtualenv(self):
             if sys.platform == 'win32' or sys.platform == 'cygwin':
                 self._venv_pip = 'Scripts\pip.exe'
 
-            proc = Popen(["virtualenv", self._pkg_venv],
-                         stdout=PIPE, stderr=PIPE)
+            proc = Popen(["virtualenv", "-p", _python_executable(),
+                          self._pkg_venv], stdout=PIPE, stderr=PIPE)
             stdout, stderr = proc.communicate()
             LOG.debug("Virtualenv stdout: %s" % stdout)
             LOG.debug("Virtualenv stderr: %s" % stderr)
@@ -265,3 +266,14 @@ def _isfile(path):
     if not path:
         return False
     return os.path.isfile(path)
+
+
+def _python_executable():
+        python_exe = find_executable('python2')
+        if python_exe is '':
+            python_exe = find_executable('python')
+
+        if python_exe is '':
+            raise Exception('Unable to locate python executable')
+
+        return python_exe