Document creating multiple tags from a single run

Dockerfile

@@ -23,6 +23,6 @@ RUN dpkg -i /data/prosody.deb
 # If using default configuration keep a process alive
 RUN echo 'daemonize = false;' | cat - /etc/prosody/prosody.cfg.lua > temp && mv temp /etc/prosody/prosody.cfg.lua
 
-EXPOSE 443 80 5222 5269 5347 5280 
+EXPOSE 443 80 5222 5269 5347 5280 5281 
 
-ENTRYPOINT prosodyctl start
+ENTRYPOINT prosodyctl start

README.md

@@ -55,7 +55,11 @@ docker run -d prosody/prosody:0.9 \
 Use the `build-docker.sh` script as follows:
 
 ```bash
-./build-docker.sh /path/to/built-image.deb version_tag
+./build-docker.sh /path/to/built-image.deb version_tag [, ...version_tag2, ...]
 ```
 
-Where argument 1 is a pointer to the build `deb` file that you'd like to make an image from and 'version_tag' is the tag you'd like to push to the Docker registry with. After running the script will clean up any images generated (but not the base images - for efficiency purposes).
+Where argument 1 is a pointer to the build `deb` file that you'd like to make an image from and 'version_tag' is the tag you'd like to push to the Docker registry with. 
+
+You can specify multiple tags by adding additional tag names to the end of the command. This is useful where a for example release 0.10.4 is made which also consitutes 'latest', '0.10-nightly', '0.10.4', '0.10' images.
+
+After running the script will clean up any images generated (but not the base images - for efficiency purposes).

build-docker.sh

@@ -13,8 +13,16 @@ fi
 echo "Starting build..."
 cp $1 ./prosody.deb
 docker build -t prosody/prosody:$2 .
+for i in "${@:3}"; do
+  echo "Also building tag $i"
+  docker build -t prosody/prosody:$i .
+done
 docker push prosody/prosody
 
 echo "Cleaning up..."
 docker rmi prosody/prosody:$2
-rm ./prosody.deb
+for i in "${@:3}"; do
+  echo "Also cleaning tag $i"  
+  docker rmi prosody/prosody:$i
+done
+rm ./prosody.deb