fetchmailconf: robustness fixes

Make sure fetchmailconf -V can complete without finding fetchmail or Tkinter.
Make sure fetchmailconf -d can complete without Tkinter.

1 files changed, 22 insertions, 13 deletions

diff --git a/fetchmailconf.py b/fetchmailconf.py
index 53434df6..1e9b2f84 100755
--- a/fetchmailconf.py
+++ b/fetchmailconf.py
@@ -26,10 +26,16 @@ import getopt
 import tempfile
 import ssl
 import subprocess
-from tkinter import *
-from tkinter.dialog import *
+try:
+    from tkinter import *
+    from tkinter.dialog import *
+    have_tk=True
+except:
+    have_tk=False
+    # define a dummy class to inherit from
+    class Frame: pass
 
-VERSION = "1.63.3"
+VERSION = "1.63.4"
 
 MIN_PY = (2, 7, 13)
 if sys.version_info < MIN_PY:
@@ -495,7 +501,7 @@ def flag2str(value, string):
     res = ""
     if value != None:
         res = res + (" ")
-        if value == FALSE:
+        if not value:
             res = res + ("no ")
         res = res + string
     return res
@@ -2183,7 +2189,7 @@ gUSiYASJpMEHhilJTEnhAlGoQqYAZQ1AiqEMZ0jDGtqQImhwwA13yMMevoQAGvGhEAWHGMOAAAA7
     dump = rcfile = None
     for (switch, val) in options:
         if switch == '-d':
-            dump = TRUE
+            dump = True
         elif switch == '-f':
             rcfile = val
         elif switch == '-h' or switch == '--help':
@@ -2207,8 +2213,7 @@ COPYING in the source or documentation directory for details.""")
             sys.exit(0)
 
     if "DISPLAY" not in os.environ:
-        print("fetchmailconf must be run under X")
-        sys.exit(1)
+        sys.exit("fetchmailconf must be run under X")
 
     # Get client host's FQDN
     hostname = socket.gethostname()
@@ -2218,12 +2223,7 @@ COPYING in the source or documentation directory for details.""")
     if not '.' in hostname:
         sys.exit('Cannot qualify my own hostname, "{}".\nFix /etc/hosts, see man 5 hosts, or add the host to DNS.'.format(hostname))
 
-    # Compute defaults
-    ConfigurationDefaults = Configuration()
-    ServerDefaults = Server()
-    UserDefaults = User()
-
-    # Read the existing configuration.
+   # Read the existing configuration.
     cmd = ['fetchmail', '--configdump', '--nosyslog']
     if rcfile:
         cmd += ['-f', rcfile]
@@ -2242,6 +2242,11 @@ COPYING in the source or documentation directory for details.""")
     except Exception as e:
         sys.exit("Can't parse output of fetchmail --configdump:\n" + str(e))
 
+    # Compute defaults
+    ConfigurationDefaults = Configuration()
+    ServerDefaults = Server()
+    UserDefaults = User()
+
     # The tricky part -- initializing objects from the configuration global
     # `Configuration' is the top level of the object tree we're going to mung.
     # The dictmembers list is used to track the set of fields the dictionary
@@ -2274,6 +2279,10 @@ COPYING in the source or documentation directory for details.""")
     if not rcfile and not dump:
         rcfile = os.environ["HOME"] + "/.fetchmailrc"
 
+    if not have_tk:
+        print("Python's tk (tkinter) module is missing. Please install it to use fetchmailconf.", file=sys.stderr)
+        sys.exit(1)
+
     # OK, now run the configuration edit
     r = Tk()