Makefile

@@ -2,7 +2,6 @@ install:
 	cp hetzner-ddns.py /usr/local/bin
 	cp etc/hetzner-ddns.conf.example /etc
 	cp etc/systemd/hetzner-ddns.service /etc/systemd/system/
-	systemctl daemon-reload
 
 uninstall:
 	rm /usr/local/bin/hetzner-ddns.py

README.md

@@ -3,8 +3,6 @@
 This script finds this machine's hostname, public IPv4 and IPv6 addresses,
 then updates the corresponding DNS records on Hetzner.
 
-**Note:** *This script is not developed, maintained or supported by Hetzner.*
-
 ## Usage
 
 ```text
@@ -30,39 +28,30 @@ Options:
 
 The instructions below were tested on Ubuntu Linux 20.04 LTS. 
 
-1. Install Python and pip:
+1. Install `python3` and `pip`:
 
-```
+    apt install python3
-sudo apt install python3 python3-pip
-```
 
 2. Install package dependencies:
 
-```
+    pip install docopt
-sudo pip3 install docopt
-```
 
 3. Clone the repository somewhere:
 
-```
+    cd /opt
     git clone https://github.com/iSoron/hetzner-ddns.git
-```
 
 4. Install the script system-wide:
 
-```
     cd hetzner-ddns
     sudo make install
-```
 
 5. Create a configuration file in `/etc/hetzner-ddns.conf` with you API token. See `/etc/hetzner-ddns.conf.example` for an example.
 
 6. Run script and enable it during boot:
 
-```
+    sudo systemctl start hetzner-ddns
-sudo make start
+    sudo systemctl enable hetzner-ddns
-sudo make enable
-```
 
 ## License
 

etc/systemd/hetzner-ddns.service

@@ -4,8 +4,8 @@ After=network-online.target
 Wants=network-online.target
 
 [Service]
-Type=simple
+Type=oneshot
-ExecStart=python3 -u /usr/local/bin/hetzner-ddns.py
+ExecStart=/usr/local/bin/hetzner-ddns.py
 
 [Install]
 WantedBy=multi-user.target

hetzner-ddns.py

@@ -20,7 +20,6 @@ Options:
   --config=<file>       Read options from configuration file
   --disable-v4          Do not update IPv4 address
   --disable-v6          Do not update IPv6 address
-  --repeat=<s>          Update DNS again every S seconds
 """
 
 from docopt import docopt
@@ -31,7 +30,6 @@ import requests
 import socket
 import sys
 import configparser
-import time
 
 
 args = docopt(__doc__)
@@ -67,7 +65,6 @@ def merge_config_file():
 
     return args
 
-
 def merge_defaults():
     global args
     default_args = {
@@ -77,7 +74,6 @@ def merge_defaults():
         "--retry-attempts": 12,
         "--retry-delay": 5,
         "--hostname": socket.gethostname(),
-        "--repeat": 3600,
     }
 
     print("Applying default options:")
@@ -100,14 +96,13 @@ if args["--zone"] is None:
 merge_defaults()
 
 
-def get_addr(
+def get_addr(url,
-    url, retry=int(args["--retry-attempts"]), delay=int(args["--retry-delay"])
+             retry=int(args["--retry-attempts"]),
-):
+             delay=int(args["--retry-delay"])):
     exception = None
     for i in range(retry):
         try:
             import urllib
-
             txt = urllib.request.urlopen(url).read()
             return txt.decode("utf-8")
         except Exception as e:
@@ -118,22 +113,19 @@ def get_addr(
 
 
 def get_all_records(zone):
-    response = requests.get(
+    response = requests.get(url="https://dns.hetzner.com/api/v1/records",
-        url="https://dns.hetzner.com/api/v1/records",
                             params={"zone_id": zone["id"]},
-        headers={"Auth-API-Token": args["--token"]},
+                            headers={"Auth-API-Token": args["--token"]})
-    )
     return response.json()["records"]
 
 
 def get_all_zones():
-    response = requests.get(
+    response = requests.get(url="https://dns.hetzner.com/api/v1/zones",
-        url="https://dns.hetzner.com/api/v1/zones",
+                            headers={"Auth-API-Token": args["--token"]})
-        headers={"Auth-API-Token": args["--token"]},
-    )
     return response.json()["zones"]
 
 
+
 def find_record(zone, name, kind="AAAA"):
     all_records = get_all_records(zone)
     for r in all_records:
@@ -157,7 +149,7 @@ def update_record(record):
             "Content-Type": "application/json",
             "Auth-API-Token": args["--token"],
         },
-        data=json.dumps(record),
+        data=json.dumps(record)
     )
     response.raise_for_status()
 
@@ -169,25 +161,13 @@ def create_record(record):
             "Content-Type": "application/json",
             "Auth-API-Token": args["--token"],
         },
-        data=json.dumps(record),
+        data=json.dumps(record)
-    )
-    response.raise_for_status()
-
-
-def delete_record(rid):
-    response = requests.delete(
-        url=f"https://dns.hetzner.com/api/v1/records/{rid}",
-        headers={
-            "Content-Type": "application/json",
-            "Auth-API-Token": args["--token"],
-        }
     )
     response.raise_for_status()
 
 
 def main():
     kinds = []
-    delay = int(args["--repeat"])
 
     if not bool(args["--disable-v4"]):
         kinds += ["A"]
@@ -198,7 +178,6 @@ def main():
     print("Finding DNS zone...")
     zone = find_zone(args["--zone"])
 
-    while True:
     for kind in kinds:
         if kind == "A":
             print("Finding public IPv4 address...")
@@ -210,30 +189,28 @@ def main():
             print("    %s" % addr)
 
         print("Finding existing %s record..." % kind)
-            rec = find_record(zone=zone, kind=kind, name=args["--hostname"])
+        rec = find_record(zone=zone,
-
+                          kind=kind,
-            if rec is not None:
+                          name=args["--hostname"])
-                if rec["value"] == addr:
-                    print("Existing record is up-to-date")
-                    continue
-
-                print("Deleting existing %s record..." % kind)
-                delete_record(rec["id"])
-                print("    done")
         
+        if rec is None:
+            print("    not found")
             print("Creating new %s record..." % kind)
-            create_record(
+            create_record({
-                {
                 "value": addr,
                 "type": kind,
                 "name": args["--hostname"],
-                    "zone_id": zone["id"],
+                "zone_id": args["--zone"],
                 "ttl": args["--ttl"],
-                }
+            })
-            )
+            print("    done")
+        else:
+            print("    found")
+            print("Updating existing %s record..." % kind)
+            rec["value"] = addr
+            rec["ttl"] = args["--ttl"]
+            update_record(rec)
             print("    done")
 
-        print(f"Sleeping for {delay} seconds...")
-        time.sleep(delay)
 
 main()