[tor-commits] [nyx/master] Simplify stem install instructions

[atagar at torproject.org]

commit 30d5fa3b206ff9227a0c34a553b53dd8951b1241
Author: Damian Johnson <atagar at torproject.org>
Date:   Mon Nov 18 17:01:40 2019 -0800

    Simplify stem install instructions
    
    Condensing and providing the same installation advice as Stem's site.
    
    Also, we cannot use shutil.which() because it was added in python 3.3...
    
      Traceback (most recent call last):
        File "./run_nyx", line 7, in <module>
          import nyx
        File "/home/atagar/Desktop/nyx/nyx/__init__.py", line 80, in <module>
          if shutil.which(cmd):
      AttributeError: 'module' object has no attribute 'which'
---
 nyx/__init__.py | 62 +++++++++++++++++----------------------------------------
 1 file changed, 18 insertions(+), 44 deletions(-)

diff --git a/nyx/__init__.py b/nyx/__init__.py
index 0efdbed..9861687 100644
--- a/nyx/__init__.py
+++ b/nyx/__init__.py
@@ -42,28 +42,27 @@ Tor curses monitoring application.
     +- halt - stops daemon panels
 """
 
+import collections
 import contextlib
+import distutils.spawn
 import getpass
 import os
 import platform
 import sys
 import threading
 import time
-import shutil
 
+# mapping of package managers to their stem installation command
 
-def is_available(command):
-   return bool(shutil.which(command))
-
-
-class PkgManagers:
-  ARCHLINUX = 'pacman'
-  GENTOO = 'emerge'
-  DEBIAN = 'apt'
-  DEBIAN_OLD = 'apt-get'
-  RED_HAT = 'yum'
-  PIP = 'pip'
-
+PACKAGE_MANAGERS = collections.OrderedDict((
+  ('apt-get', 'sudo apt-get install python-stem'),  # Debian
+  ('dnf', 'sudo dnf install python-stem'),          # Redhat
+  ('pacman', 'sudo pacman -S python-stem'),         # Archlinux
+  ('emerge', 'sudo emerge stem'),                   # Gentoo
+  ('pkg', 'pkg install security/py-stem'),          # FreeBSD
+  ('pkg_add', 'pkg_add py-stem'),                   # OpenBSD
+  ('pip', 'pip install stem'),                      # PyPI
+))
 
 try:
   import stem
@@ -74,38 +73,13 @@ try:
   import stem.util.log
   import stem.util.system
   import stem.util.tor_tools
-except ImportError as exc:
-  if isinstance(exc, ModuleNotFoundError) and str(exc) == "No module named 'stem'":
-    missing_pkg_name = 'python-stem'
-    pkg_manager_not_found = False
-    if is_available(PkgManagers.DEBIAN):
-      pkg_install_procedure = PkgManagers.DEBIAN + ' install'
-    elif is_available(PkgManagers.DEBIAN_OLD):
-      pkg_install_procedure = PkgManagers.DEBIAN_OLD + ' install'
-    elif is_available(PkgManagers.GENTOO):
-      missing_pkg_name = 'net-libs/stem'
-      pkg_install_procedure = PkgManagers.GENTOO + ' --ask'
-    elif is_available(PkgManagers.RED_HAT):
-      pkg_install_procedure = PkgManagers.RED_HAT + ' install'
-    elif is_available(PkgManagers.ARCHLINUX):
-      pkg_install_procedure = PkgManagers.ARCHLINUX + ' -Syu'
-    elif is_available(PkgManagers.PIP):
-      missing_pkg_name = 'stem'
-      pkg_install_procedure = PkgManagers.PIP + ' install'
-    else:
-      pkg_manager_not_found = True
-      pkg_install_procedure = ', you can find it at https://stem.torproject.org/download.html'
-
-    require_message = 'nyx requires python-stem'
-    if pkg_manager_not_found:
-      final_message = require_message + pkg_install_procedure
-    else:
-      final_message = require_message + ', try running:\n\nsudo ' + pkg_install_procedure + ' ' + missing_pkg_name + '\n'
-
-    print(final_message)
-  else:
-    print('Unable to start nyx: %s' % exc)
+except ImportError:
+  for cmd, stem_install in PACKAGE_MANAGERS.items():
+    if distutils.spawn.find_executable(cmd):
+      print("nyx requires stem, try running '%s'" % stem_install)
+      sys.exit(1)
 
+  print('nyx requires stem, you can find it at https://stem.torproject.org/download.html')
   sys.exit(1)