allow passing arguments to the client script; change default server to ipv4.ns.ralfj.de

[dyn-nsupdate.git] / client-scripts / dyn-ns-client

diff --git a/client-scripts/dyn-ns-client b/client-scripts/dyn-ns-client
index 6af3934799f83a529950b10912ed74f3ab84c21f..ef0e9b85275782ab4f12df9b6eb09e5d51bcfaf2 100755 (executable)
--- a/client-scripts/dyn-ns-client
+++ b/client-scripts/dyn-ns-client
@@ -1,39 +1,87 @@
 #!/usr/bin/python3
-import urllib.request, socket, sys
+# Copyright (c) 2014, Ralf Jung <post@ralfj.de>
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+# 1. Redistributions of source code must retain the above copyright notice, this
+#    list of conditions and the following disclaimer. 
+# 2. Redistributions in binary form must reproduce the above copyright notice,
+#    this list of conditions and the following disclaimer in the documentation
+#    and/or other materials provided with the distribution.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# 
+# The views and conclusions contained in the software and documentation are those
+# of the authors and should not be interpreted as representing official policies, 
+# either expressed or implied, of the FreeBSD Project.
+
+import urllib.request, socket, sys, argparse
 
 # configuration variables
-server = 'ns.ralfj.de'
+server = 'ipv4.ns.ralfj.de'
 domains = ['domain.dyn.ralfj.de'] # list of domains to update
 password = 'yourpassword'
 # END of configuration variables
 
+# allow overwriting some values on the command-line
+parser = argparse.ArgumentParser(description='Update a domain managed by a dyn-nsupdate server')
+parser.add_argument("-s", "--server",
+                    dest="server", default=server,
+                    help="The dyn-nsupdate server")
+parser.add_argument("-p", "--password",
+                    dest="password", default=password,
+                    help="The password used to update the domains")
+parser.add_argument("-v", "--verbose",
+                    action="store_true", dest="verbose",
+                    help="Be more verbose")
+parser.add_argument("domains",  metavar='DOMAIN', nargs='*', default=domains,
+                    help="The domains to update")
+args = parser.parse_args()
+
 def urlopen(url):
-       return urllib.request.urlopen(url).read().decode('utf-8').strip()
+    return urllib.request.urlopen(url).read().decode('utf-8').strip()
 
-myip = urlopen('https://'+server+'/checkip')
+myip = urlopen('https://'+args.server+'/checkip')
 
 def update_domain(domain):
-       '''Update the given domain, using the global server, user, password. Returns True on success, False on failure.'''
-       global myip
-       # check if the domain is already mapped to our current IP
-       domainip = socket.gethostbyname(domain)
-       if myip == domainip:
-               # nothing to do
-               return True
-
-       # we need to update the IP
-       result = urlopen('https://'+server+'/update?password='+urllib.parse.quote(password)+'&domain='+urllib.parse.quote(domain)+'&ip='+urllib.parse.quote(myip))
-       if 'good '+myip == result: 
-               # all went all right
-               return True
-       else:
-               # Something went wrong
-               print("Unexpected answer from server",server,"while updating",domain,"to",myip)
-               print(result)
-               return False
+    '''Update the given domain, using the global server, user, password. Returns True on success, False on failure.'''
+    global myip, args
+    # check if the domain is already mapped to our current IP
+    try:
+        domainip = socket.gethostbyname(domain)
+        if myip == domainip:
+            # nothing to do
+            if args.verbose:
+                print("Domain",domain,"already up-to-date, not doing anything")
+            return True
+    except socket.gaierror: # domain not found
+        pass
+
+    # we need to update the IP
+    result = urlopen('https://'+args.server+'/update?password='+urllib.parse.quote(args.password)+'&domain='+urllib.parse.quote(domain)+'&ip='+urllib.parse.quote(myip))
+    if 'good '+myip == result: 
+        print("Successfully updated domain",domain,"to",myip)
+        # all went all right
+        return True
+    else:
+        # Something went wrong
+        print("Unexpected answer from server",server,"while updating",domain,"to",myip)
+        print(result)
+        return False
 
 exitcode = 0
-for domain in domains:
-       if not update_domain(domain):
-               exitcode = 1
+for domain in args.domains:
+    if not update_domain(domain):
+        exitcode = 1
 sys.exit(exitcode)