docs and examples: python bindings

* Woumd up the "what's new" section.
* Added an example for sending a key to the keyservers via hkp4py.
* Updated the export key code to use a more complete check for the
  $GNUPGHOME location.
* Expanded on the installation and reinstallation troubleshooting
  section.

Tested-by: Ben McGinnes <[email protected]>
Signed-off-by: Ben McGinnes <[email protected]>

5 files changed, 170 insertions, 16 deletions

diff --git a/lang/python/examples/howto/export-key.py b/lang/python/examples/howto/export-key.py
index 80768fe7..c17f2471 100755
--- a/lang/python/examples/howto/export-key.py
+++ b/lang/python/examples/howto/export-key.py
@@ -51,12 +51,26 @@ else:
     logrus = input("Enter the UID matching the key(s) to export: ")
     homedir = input("Enter the GPG configuration directory path (optional): ")
 
-if homedir.startswith("~"):
-    if os.path.exists(os.path.expanduser(homedir)) is True:
-        c.home_dir = os.path.expanduser(homedir)
+if len(homedir) == 0:
+    homedir = None
+elif homedir.startswith("~"):
+    userdir = os.path.expanduser(homedir)
+    if os.path.exists(userdir) is True:
+        homedir = os.path.realpath(userdir)
+    else:
+        homedir = None
+else:
+    homedir = os.path.realpath(homedir)
+
+if os.path.exists(homedir) is False:
+    homedir = None
+else:
+    if os.path.isdir(homedir) is False:
+        homedir = None
     else:
         pass
-elif os.path.exists(homedir) is True:
+
+if homedir is not None:
     c.home_dir = homedir
 else:
     pass
diff --git a/lang/python/examples/howto/export-minimised-key.py b/lang/python/examples/howto/export-minimised-key.py
index 9d5f8488..a5a453ce 100755
--- a/lang/python/examples/howto/export-minimised-key.py
+++ b/lang/python/examples/howto/export-minimised-key.py
@@ -51,12 +51,26 @@ else:
     logrus = input("Enter the UID matching the key(s) to export: ")
     homedir = input("Enter the GPG configuration directory path (optional): ")
 
-if homedir.startswith("~"):
-    if os.path.exists(os.path.expanduser(homedir)) is True:
-        c.home_dir = os.path.expanduser(homedir)
+if len(homedir) == 0:
+    homedir = None
+elif homedir.startswith("~"):
+    userdir = os.path.expanduser(homedir)
+    if os.path.exists(userdir) is True:
+        homedir = os.path.realpath(userdir)
+    else:
+        homedir = None
+else:
+    homedir = os.path.realpath(homedir)
+
+if os.path.exists(homedir) is False:
+    homedir = None
+else:
+    if os.path.isdir(homedir) is False:
+        homedir = None
     else:
         pass
-elif os.path.exists(homedir) is True:
+
+if homedir is not None:
     c.home_dir = homedir
 else:
     pass
diff --git a/lang/python/examples/howto/export-secret-key.py b/lang/python/examples/howto/export-secret-key.py
index ccc9f45d..e7d4e3af 100755
--- a/lang/python/examples/howto/export-secret-key.py
+++ b/lang/python/examples/howto/export-secret-key.py
@@ -54,12 +54,26 @@ else:
     logrus = input("Enter the UID matching the secret key(s) to export: ")
     homedir = input("Enter the GPG configuration directory path (optional): ")
 
-if homedir.startswith("~"):
-    if os.path.exists(os.path.expanduser(homedir)) is True:
-        c.home_dir = os.path.expanduser(homedir)
+if len(homedir) == 0:
+    homedir = None
+elif homedir.startswith("~"):
+    userdir = os.path.expanduser(homedir)
+    if os.path.exists(userdir) is True:
+        homedir = os.path.realpath(userdir)
+    else:
+        homedir = None
+else:
+    homedir = os.path.realpath(homedir)
+
+if os.path.exists(homedir) is False:
+    homedir = None
+else:
+    if os.path.isdir(homedir) is False:
+        homedir = None
     else:
         pass
-elif os.path.exists(homedir) is True:
+
+if homedir is not None:
     c.home_dir = homedir
 else:
     pass
diff --git a/lang/python/examples/howto/export-secret-keys.py b/lang/python/examples/howto/export-secret-keys.py
index f2f1ccde..f0fddc6d 100755
--- a/lang/python/examples/howto/export-secret-keys.py
+++ b/lang/python/examples/howto/export-secret-keys.py
@@ -63,12 +63,26 @@ else:
     logrus = input("Enter the UID matching the secret key(s) to export: ")
     homedir = input("Enter the GPG configuration directory path (optional): ")
 
-if homedir.startswith("~"):
-    if os.path.exists(os.path.expanduser(homedir)) is True:
-        c.home_dir = os.path.expanduser(homedir)
+if len(homedir) == 0:
+    homedir = None
+elif homedir.startswith("~"):
+    userdir = os.path.expanduser(homedir)
+    if os.path.exists(userdir) is True:
+        homedir = os.path.realpath(userdir)
+    else:
+        homedir = None
+else:
+    homedir = os.path.realpath(homedir)
+
+if os.path.exists(homedir) is False:
+    homedir = None
+else:
+    if os.path.isdir(homedir) is False:
+        homedir = None
     else:
         pass
-elif os.path.exists(homedir) is True:
+
+if homedir is not None:
     c.home_dir = homedir
 else:
     pass
diff --git a/lang/python/examples/howto/send-key-to-keyserver.py b/lang/python/examples/howto/send-key-to-keyserver.py
new file mode 100755
index 00000000..3541b198
--- /dev/null
+++ b/lang/python/examples/howto/send-key-to-keyserver.py
@@ -0,0 +1,98 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+from __future__ import absolute_import, division, unicode_literals
+
+import gpg
+import hkp4py
+import os.path
+import sys
+
+# Copyright (C) 2018 Ben McGinnes <[email protected]>
+#
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free Software
+# Foundation; either version 2 of the License, or (at your option) any later
+# version.
+#
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of the GNU Lesser General Public License as published by the Free
+# Software Foundation; either version 2.1 of the License, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE.  See the GNU General Public License and the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License and the GNU
+# Lesser General Public along with this program; if not, see
+# <http://www.gnu.org/licenses/>.
+
+print("""
+This script sends one or more public keys to the SKS keyservers and is
+essentially a slight variation on the export-key.py script.
+
+The default is to send all keys if there is no pattern or search term.
+""")
+
+c = gpg.Context(armor=True)
+server = hkp4py.KeyServer("hkps://hkps.pool.sks-keyservers.net")
+
+if len(sys.argv) >= 3:
+    logrus = sys.argv[1]
+    homedir = sys.argv[2]
+elif len(sys.argv) == 2:
+    logrus = sys.argv[1]
+    homedir = input("Enter the GPG configuration directory path (optional): ")
+else:
+    logrus = input("Enter the UID matching the key(s) to export: ")
+    homedir = input("Enter the GPG configuration directory path (optional): ")
+
+if len(homedir) == 0:
+    homedir = None
+elif homedir.startswith("~"):
+    userdir = os.path.expanduser(homedir)
+    if os.path.exists(userdir) is True:
+        homedir = os.path.realpath(userdir)
+    else:
+        homedir = None
+else:
+    homedir = os.path.realpath(homedir)
+
+if os.path.exists(homedir) is False:
+    homedir = None
+else:
+    if os.path.isdir(homedir) is False:
+        homedir = None
+    else:
+        pass
+
+if homedir is not None:
+    c.home_dir = homedir
+else:
+    pass
+
+if len(logrus) > 0:
+    try:
+        export_result = c.key_export(pattern=logrus)
+    except Exception as e:
+        print(e)
+        export_result = None
+else:
+    export_result = c.key_export(pattern=None)
+
+if export_result is not None:
+    try:
+        try:
+            send_result = server.add(export_result)
+        except:
+            send_result = server.add(export_result.decode())
+        if send_result is not None:
+            print(send_result)
+        else:
+            pass
+    except Exception as e:
+        print(e)
+else:
+    pass