dep_check: stop using unsupported internal pip functions

  pip.get_installed_distributions() is in internal function
  that was never meant to be externally called and has since
  been locked out by external functions.

  Lets switch over to the supported function in setuptools
  pkg_resources.get_distribution() to search the installed
  packages.

  See: pypa/pip#5243
  Fixes: 255

dep_check.py

@@ -1,20 +1,18 @@
-import pip
+import pkg_resources
 import sys
 
 def check_dependency():
- list_deps = []
  missing_deps = []
 
- with open('requirements.txt') as f:
- list_deps = f.read().splitlines()
-
- pip_list = sorted([(i.key) for i in pip.get_installed_distributions()])
-
- for req_dep in list_deps:
- if req_dep not in pip_list:
- missing_deps.append(req_dep)
+ with open('requirements.txt', 'r') as reqs_file:
+ for req_dep in reqs_file.read().splitlines():
+ try:
+ pkg_resources.get_distribution(req_dep)
+ except pkg_resources.DistributionNotFound:
+ missing_deps.append(req_dep)
 
  if missing_deps:
- print "You are missing a module for Datasploit. Please install them using: "
- print "pip install -r requirements.txt"
+ print "You are missing the following module(s) needed to run DataSploit:"
+ print ", ".join(missing_deps)
+ print "Please install them using: `pip install -r requirements.txt`"
  sys.exit()