initial commit

.gitignore

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+config.json
+log.txt

README.md

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+# Dyn-Gandi
+A DNS record updater for [Gandi's LiveDNS](https://api.gandi.net/docs/livedns/) API.
+This script is heavily inspired by [dyn-gandi](https://github.com/Danamir/dyn-gandi).
+
+## How it works
+This script determines the your server's current IP by querying the resolvers defined in the config file.
+After that it reads the current state of the domains and subdomains you specified of Gandi.
+Should the IP address of a subdomain not match your current IP it will be updated.
+The subdomain will be created should it not already exist.
+
+## Note
+The current implementation only allows for one entry per subdomain.
+Meaning that should you have a TXT and a CNAME record for a subdomain that is in the config file, then both these entries will be deleted and replaced by a single A name record.
+
+## How to use
+First, get your API key from https://account.gandi.net/en/users/USER/security where `USER` is your Gandi username.
+On first run the program will create a minimal, yet complete `config.json` in the same directory it is being run in.  
+Next, enter the API key into the configuration file and assign domains to it.
+The domains are keys to a list of subdomain for a given domain you wish to monitor.
+The below example is complete and should explain itself.
+Resolvers are queried one after another until one returns a valid IP.
+
+`config.json`
+```json
+{
+  "api": {
+    "<Your-API-Key>": {
+      "example.com": [ "@", "www", "sub1" ],
+      "example.org": [ "@", "www", "sub1", "sub2" ]
+    }
+  },
+  "ttl": 3600,
+  "resolvers": [
+    "https://ifconfig.me/ip"
+    "https://me.gandi.net"
+  ],
+  "log_path": "./log.txt"
+}
+```
+
+## Features
+* Support for arbitrarily many domains and records through a nested data structure.
+* Small codebase.
+* Logging
+
+## Limitations
+* Right now only IPv4 addresses are supported
+* Every record is only allowed one A record.
+* Extra records (TXT, CNAME and such) will get deleted on update. 
+
+## TODO
+* Testing
+* Command line options controlling: dry-run, config, log, verbosity, force
+* Per subdomain TTL
+* Nix Flake support with exported config and service options
+* Better documentation
+* Better logging
+* Support IPv6
+* Remember other record types (TXT, etc.)
+* Detect TTL change and update even when the IP is the same

dyn-gandi.py

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+import requests, json, re
+from datetime import datetime
+
+def loadSettings() -> dict:
+    # TODO: check integrity
+    try:
+        with open('config.json', 'r') as file:
+            return json.load(file)
+    except FileNotFoundError:
+        sample_config = {
+            'api': {},
+            'ttl': 3600,
+            'resolvers': [ 'https://ifconfig.me' ],
+            'log_path': './log.txt'
+        }
+
+        with open('config.json', 'w') as file:
+            json.dump(sample_config, file, indent = 2)
+
+        return sample_config
+
+# Appends logline at the end of the file file with a timestamp
+def log(logline: str, path: str = './log.txt') -> None:
+    with open(path, 'a') as file:
+        file.write(f"[{datetime.now().strftime('%Y-%m-%d %H:%M:%S')}]{logline}\n")
+
+# Go through resolvers until one retuns an IP
+def getCurrentIP(resolvers: list[str], log: callable) -> None | str:
+    for resolver in resolvers:
+        response = requests.request('GET', resolver)
+        if response.status_code == 200:
+            current_ip = response.text.strip()
+            is_ipv4 = re.search('^((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\.?\\b){4}$', current_ip) is not None
+            if is_ipv4:
+                log(f"[OK][{resolver}] Current IP: '{current_ip}'")
+                return current_ip # Break if we have found our IP
+            else:
+                log(f"[ERROR][{resolver}] '{current_ip}' is not IPv4")
+        else:
+            log(f"[ERROR][{resolver}][{response.status_code}] {response.text}")
+    return None
+
+# Returns the records that need to be renewed
+# TODO: Also detect TTL change
+def checkRecords(api: dict, current_ip: str, log: callable) -> dict:
+    records_to_renew = api
+    for key, domains in api.items():
+        headers = { 'authorization': f"Apikey {key}" }
+        for domain, records in domains.items():
+            response = requests.request('GET', f"https://api.gandi.net/v5/livedns/domains/{domain}/records?rrset_type=A", headers = headers)
+            if response.status_code == 200:
+                records_to_renew[key][domain] = list(set(records_to_renew[key][domain]) - set(record['rrset_name'] for record in (filter(lambda x: current_ip in x['rrset_values'], json.loads(response.text)))))
+            else:
+                log(f"[ERROR][{domain}][{response.status_code}] {response.text}")
+
+    return records_to_renew
+
+# Updates the records and reates them if they don't exist
+def renewRecords(records, current_ip, log, ttl = 3600):
+    payload = json.dumps({
+        'items': [{
+            'rrset_type': 'A',
+            'rrset_values': [ current_ip ],
+            'rrset_ttl': ttl
+        }]
+    })
+
+    for key, domains in records.items():
+        headers = {
+            'authorization': f"Apikey {key}",
+            'content-type': 'application/json',
+        }
+
+        for domain, records in domains.items():
+            for record in records:
+                response = requests.request('PUT', f"https://api.gandi.net/v5/livedns/domains/{domain}/records/{record}", data = payload, headers = headers)
+                if response.status_code == 201:
+                    log(f"[OK][{domain}][{record}] Renewed with IP '{current_ip}'")
+                else:
+                    log(f"[ERROR][{domain}][{record}][{response.status_code}] {response.text}")
+
+def main():
+    settings = loadSettings()
+    log_path = settings['log_path']
+    ttl = settings['ttl']
+    log = lambda x: log(x, path = log_path)
+
+    current_ip = getCurrentIP(settings['resolvers'], log)
+    records_to_renew = checkRecords(settings['api'], current_ip, log)
+    renewRecords(records_to_renew, current_ip, log, ttl = ttl)
+
+if __name__ == '__main__':
+    main()