Merge pull request #2 from FarrowStrange/hetzner-api-dyndns-2007250936

[hetzner-api-dyndns-2007250936] complete rework
FarrowStrange · Jul 26, 2020 · 6b8285a · 6b8285a
2 parents 403b087 + a90e67a
commit 6b8285a
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diff --git a/README.md b/README.md
@@ -2,7 +2,7 @@
 
 A small script to dynamically update DNS records using the Hetzner DNS-API. Feel free to propose changes.
 
-**Hetzner DNS API Doc**
+**Hetzner DNS API Doc:**
 
 https://dns.hetzner.com/api-docs/
 
@@ -11,15 +11,15 @@ https://dns.hetzner.com/api-docs/
 First, a new access token must be created in the DNS Console. This should be copied immediately, because for security reasons it will not be possible to display the token later. 
 
 ## Get all Zones
-Get all zones and copy zone ID 
+Get all zones and copy the desired zone ID.
 ```
 curl "https://dns.hetzner.com/api/v1/zones" -H \
 'Auth-API-Token: ${apitoken}'
 ```
 
 ## Add Record
-Use the previously obtained zone id to create a dns record. 
-In the output you get the record ID. This is needed in the script and should therefore be noted.
+Use the previously obtained zone ID to create a dns record. 
+In the output you get the record ID. This is needed for the script and should therefore be noted.
 ```
 curl -X "POST" "https://dns.hetzner.com/api/v1/records" \
      -H 'Content-Type: application/json' \
@@ -34,12 +34,45 @@ curl -X "POST" "https://dns.hetzner.com/api/v1/records" \
 ```
 
 # Usage
-Insert the Access token and the Zone and Record ID in the script. 
+For security reasons, the access token is stored directly in the script. Enter your previously created token here.
+```
+...
+auth_api_token=''
+...
+```
+
+As soon as the token is deposited, the script can be called with the appropriate parameters. This allows several DynDNS records to be created in different zones. Optionally, the TTL and the record type can be specified. It is advisable to keep the TTL as low as possible, so that changed records are used as soon as possible.
+```
+./dyndns.sh -z <Zone ID> -r <Record ID> -n <Record Name> [-t <TTL>] [-T <Record Type>]
+```
+
+To keep your DynDNS Records up to date, you have to create a cronjob that calls the script periodically. 
 
-To keep your DynDNS Records up to date, you create a cronjob that calls the script periodically. 
-It is advisable to keep the TTL as low as possible, so that changed records are used as soon as possible.
+**Example:** Check DynDNS every 5 Minutes
 ```
-api_auth_token=${apitoken}
-api_zone=${zoneID}
-api_record=${recordID}
-```
+*/5 0 * * * /usb/bin/dyndns.sh -z 98jFjsd8dh1GHasdf7a8hJG7 -r AHD82h347fGAF1 -n dyn
+```
+
+# Help
+Type `-h` to display help page.
+```
+./dyndns -h
+```
+```
+exec: ./dyndns.sh -z <Zone ID> -r <Record ID> -n <Record Name>
+
+parameters:
+  -z  - Zone ID
+  -r  - Record ID
+  -n  - Record name
+
+optional parameters:
+  -t  - TTL (Default: 60)
+  -T  - Record type (Default: A)
+
+help:
+  -h  - Show Help 
+
+example:
+  .exec: ./dyndns.sh -z 98jFjsd8dh1GHasdf7a8hJG7 -r AHD82h347fGAF1 -n dyn
+``` 
diff --git a/dyndns.sh b/dyndns.sh
@@ -1,35 +1,92 @@
 #!/bin/bash
-# DynDNS Script for Hetzner API by FarrowStrange
-# V0.1
+# DynDNS Script for Hetzner DNS API by FarrowStrange
+# v1.0
 
-api_auth_token=
-api_zone=
-api_record=
+auth_api_token=''
+record_ttl='60'
+record_type='A'
 
-pub_addr=`curl -s ifconfig.me`
-api_dyn_addr=`curl -s "https://dns.hetzner.com/api/v1/records/${api_record}" -H 'Auth-API-Token: '${api_auth_token} | cut -d ',' -f 4 | cut -d '"' -f 4`
+display_help() {
+  cat <<EOF
 
-if [[ $pub_addr == $api_dyn_addr ]]; then
-  echo "DNS record is up to date - nothing to to."
+exec: ./dyndns.sh -z <Zone ID> -r <Record ID> -n <Record Name>
 
-else
-  echo "DNS record is no longer valid - updating record" 
+parameters:
+  -z  - Zone ID
+  -r  - Record ID
+  -n  - Record name
+
+optional parameters:
+  -t  - TTL (Default: 60)
+  -T  - Record type (Default: A)
+
+help:
+  -h  - Show Help 
+
+example:
+  .exec: ./dyndns.sh -z 98jFjsd8dh1GHasdf7a8hJG7 -r AHD82h347fGAF1 -n dyn
+
+EOF
+  exit 1
+}
+
+while getopts ":z:r:n:t:T:h:" opt; do
+  case "$opt" in
+    z  ) zone_id="${OPTARG}";;
+    r  ) record_id="${OPTARG}";;
+    n  ) record_name="${OPTARG}";;
+    t  ) record_ttl="${OPTARG}";;
+    T  ) record_type="${OPTARG}";;
+    h  ) display_help;;
+    \? ) echo "Invalid option: -$OPTARG" >&2; exit 1;;
+    :  ) echo "Missing option argument for -$OPTARG" >&2; exit 1;;
+    *  ) echo "Unimplemented option: -$OPTARG" >&2; exit 1;;
+  esac
+done
 
+if [[ "${zone_id}" = "" ]]; then 
+  echo "Missing option for zone ID: -z <Zone ID>"
+  echo "Use -h to display help."
+  exit 1
+elif [[ "${record_id}" = "" ]]; then
+  echo "Mission option for record ID: -r <Record ID>"
+  echo "Use -h to display help."
+  exit 1
+elif [[ "${record_name}" = "" ]]; then
+  echo "Mission option for record name: -n <Record Name>"
+  echo "Use -h to display help."
+  exit 1
+fi
+
+if [[ "${auth_api_token}" = "" ]]; then
+  echo "No Auth API Token specified. Please reference at the top of the Script."
+  exit 1
+fi
+
+
+cur_pub_addr=`curl -s https://ifconfig.me`
+cur_dyn_addr=`curl -s "https://dns.hetzner.com/api/v1/records/${record_id}" -H 'Auth-API-Token: '${auth_api_token} | cut -d ',' -f 4 | cut -d '"' -f 4`
+
+if [[ $cur_pub_addr == $cur_dyn_addr ]]; then
+  echo "DNS record \"${record_name}\" is up to date - nothing to to."
+  exit 0
+else
+  echo "DNS record \"${record_name}\" is no longer valid - updating record" 
 
-  curl -s -X "PUT" "https://dns.hetzner.com/api/v1/records/${api_record}" \
+  curl -s -X "PUT" "https://dns.hetzner.com/api/v1/records/${record_id}" \
     -H 'Content-Type: application/json' \
-    -H 'Auth-API-Token: '${api_auth_token} \
+    -H 'Auth-API-Token: '${auth_api_token} \
     -d $'{
-      "value": "'${pub_addr}'",
-      "ttl": 60,
-      "type": "A",
-      "name": "gw",
-      "zone_id": "'${api_zone}'"
+      "value": "'${cur_pub_addr}'",
+      "ttl": '${record_ttl}',
+      "type": "'${record_type}'",
+      "name": "'${record_name}'",
+      "zone_id": "'${zone_id}'"
     }'
 
   if [[ $? != 0 ]]; then
-    echo "Unable to update record"
-  else
-    echo "DNS record updated successfully"
+     echo "Unable to update record: \"${record_name}\""
+   else
+     echo "DNS record \"${record_name}\" updated successfully"
   fi
-fi
+fi