added option for alternate (alias) domain, added docker-compose.yml, formatting, docs

README.md

@@ -13,12 +13,21 @@ Automatically generates Let's Encrypt certificates using a lightweight Docker co
 * `DUCKDNS_TOKEN`: Duck DNS account token (obtained from [Duck DNS](https://www.duckdns.org)) (*required*)
 * `DUCKDNS_DOMAIN`: Full Duck DNS domain (e.g. `test.duckdns.org`) (*required*)
 * `LETSENCRYPT_EMAIL`: Email used for certificate renewal notifications (optional)
+* `LETSENCRYPT_DOMAIN`: Domain to generate SSL cert for. By default SSL certificate is generated for `DUCKDNS_DOMAIN` (optional)
 * `LETSENCRYPT_WILDCARD`: `true` or `false`, indicating whether the SSL certificate should be for subdomains *only* of `DUCKDNS_DOMAIN` (i.e. `*.test.duckdns.org`), or for the main domain *only* (i.e. `test.duckdns.org`) (optional, default: `false`)
 * `TESTING`: `true` or `false`, indicating whether a staging SSL certificate should be generated or not (optional, default: `false`)
 * `UID`: User ID to apply to Let's Encrypt files generated (optional, recommended, default: `0` - root)
 * `GID`: Group ID to apply to Let's Encrypt files generated (optional, recommended, default: `0` - root)
 
-**Note:** The format of `DUCKDNS_DOMAIN` should be the same regardless of the value of `LETSENCRYPT_WILDCARD`.
+## Notes
+
+* The format of `DUCKDNS_DOMAIN` should be the same regardless of the value of `LETSENCRYPT_WILDCARD`.
+
+* In order to use `LETSENCRYPT_DOMAIN` feature, the following DNS records need to be created for ACME authentication
+```
+   <LETSENCRYPT_DOMAIN> CNAME -> <DUCKDNS_DOMAIN>
+   _acme-challenge.<<LETSENCRYPT_DOMAIN> CNAME -> _acme-challenge.<DUCKDNS_DOMAIN>
+```
 
 ## Volumes
 

docker-compose.yml

@@ -0,0 +1,18 @@
+version: '2.4'
+
+services:
+  duckdns-letsencrypt:
+    build: .
+    restart: unless-stopped
+    volumes:
+      - ./certs:/etc/letsencrypt
+    environment:
+      # mandatory
+      - "DUCKDNS_TOKEN=<your-duckdns-token>"
+      - "DUCKDNS_DOMAIN=<your-duckdns-domain>"
+      # optional
+      # - "LETSENCRYPT_DOMAIN=<alternative-domain>"
+      # - "LETSENCRYPT_EMAIL=<email-address>"
+      # - "LETSENCRYPT_WILDCARD=false"
+      # - "TESTING=false"
+

scripts/auth.sh

@@ -1,3 +1,3 @@
 #!/bin/sh
-[[ "$(curl -s "https://www.duckdns.org/update?domains=${CERTBOT_DOMAIN%.duckdns.org}&token=${DUCKDNS_TOKEN}&txt=${CERTBOT_VALIDATION}")" = "OK" ]]
+[[ "$(curl -s "https://www.duckdns.org/update?domains=${DUCKDNS_DOMAIN%.duckdns.org}&token=${DUCKDNS_TOKEN}&txt=${CERTBOT_VALIDATION}")" = "OK" ]]
 

scripts/cleanup.sh

@@ -1,2 +1,2 @@
 #!/bin/sh
-[[ "$(curl -s "https://www.duckdns.org/update?domains=${CERTBOT_DOMAIN%.duckdns.org}&token=${DUCKDNS_TOKEN}&txt=${CERTBOT_VALIDATION}&clear=true")" = "OK" ]]
+[[ "$(curl -s "https://www.duckdns.org/update?domains=${DUCKDNS_DOMAIN%.duckdns.org}&token=${DUCKDNS_TOKEN}&txt=${CERTBOT_VALIDATION}&clear=true")" = "OK" ]]

scripts/start.sh

@@ -16,12 +16,17 @@ if [ -z "$LETSENCRYPT_EMAIL" ]; then
   echo "INFO: You will not receive SSL certificate expiration notices"
 fi
 
+# Set LETSENCRYPT_DOMAIN to DUCKDNS_DOMAIN if not specified
+if [ -z "$LETSENCRYPT_DOMAIN" ]; then
+  echo "INFO: No LETSENCRYPT_DOMAIN, using DUCKDNS_DOMAIN"
+  LETSENCRYPT_DOMAIN=$DUCKDNS_DOMAIN
+fi
+
 # Set certificate url based on LETSENCRYPT_WILDCARD value
 if [ "$LETSENCRYPT_WILDCARD" = "true" ]; then
   echo "INFO: A wildcard SSL certificate will be created"
-  LETSENCRYPT_DOMAIN="*.$DUCKDNS_DOMAIN"
+  LETSENCRYPT_DOMAIN="*.$LETSENCRYPT_DOMAIN"
 else
-  LETSENCRYPT_DOMAIN="$DUCKDNS_DOMAIN"
   LETSENCRYPT_WILDCARD="false"
 fi
 
@@ -39,6 +44,7 @@ fi
 # Print variables
 echo "DUCKDNS_TOKEN: $DUCKDNS_TOKEN"
 echo "DUCKDNS_DOMAIN: $DUCKDNS_DOMAIN"
+echo "LETSENCRYPT_DOMAIN: $LETSENCRYPT_DOMAIN"
 echo "LETSENCRYPT_EMAIL: $LETSENCRYPT_EMAIL"
 echo "LETSENCRYPT_WILDCARD: $LETSENCRYPT_WILDCARD"
 echo "TESTING: $TESTING"
@@ -58,23 +64,25 @@ else
   unset TEST_PARAM
 fi
 
-echo "certbot certonly --manual --preferred-challenges dns --manual-auth-hook \
+echo "certbot certonly --manual --preferred-challenges dns \
-  /scripts/auth.sh --manual-cleanup-hook /scripts/cleanup.sh \
+  --manual-auth-hook /scripts/auth.sh \
+  --manual-cleanup-hook /scripts/cleanup.sh \
   $EMAIL_PARAM -d $LETSENCRYPT_DOMAIN \
   --agree-tos --manual-public-ip-logging-ok --keep $TEST_PARAM"
 
 # Create certificates
-certbot certonly --manual --preferred-challenges dns --manual-auth-hook \
+certbot certonly --manual --preferred-challenges dns \
-  /scripts/auth.sh --manual-cleanup-hook /scripts/cleanup.sh \
+  --manual-auth-hook /scripts/auth.sh \
+  --manual-cleanup-hook /scripts/cleanup.sh \
   $EMAIL_PARAM -d $LETSENCRYPT_DOMAIN \
   --agree-tos --manual-public-ip-logging-ok --keep $TEST_PARAM
 
 chown -R $UID:$GID /etc/letsencrypt
 
 # Check for successful certificate generation
-if [ ! -d "/etc/letsencrypt/live/${DUCKDNS_DOMAIN}" ] || \
+if [ ! -d "/etc/letsencrypt/live/${LETSENCRYPT_DOMAIN#\*\.}" ] || \
-   [ ! -f "/etc/letsencrypt/live/${DUCKDNS_DOMAIN}/fullchain.pem" ] || \
+   [ ! -f "/etc/letsencrypt/live/${LETSENCRYPT_DOMAIN#\*\.}/fullchain.pem" ] || \
-   [ ! -f "/etc/letsencrypt/live/${DUCKDNS_DOMAIN}/privkey.pem" ]; then
+   [ ! -f "/etc/letsencrypt/live/${LETSENCRYPT_DOMAIN#\*\.}/privkey.pem" ]; then
   echo "ERROR: Failed to create SSL certificates"
   exit 1
 fi