Include the captcha examples in the container and how to use them (#65)

ecs/Dockerfile

@@ -24,8 +24,11 @@ RUN mkdir runtime \
     && cp releases/*/start.boot bin \
     && echo 'beam_lib:strip_files(filelib:wildcard("lib/*/ebin/*beam")), init:stop().' | erts*/bin/erl -boot start_clean >/dev/null \
     && mv erts*/bin/* bin \
+    && EJABBERD_VERSION=`(cd releases; ls -1 -d *.*.*)` \
     && rm -rf releases erts* bin/*src bin/dialyzer bin/typer \
     && rm bin/ejabberd bin/ejabberd.bat \
+    && mkdir lib/ejabberd-$EJABBERD_VERSION/priv/bin \
+    && cp /ejabberd/tools/captcha*sh lib/ejabberd-$EJABBERD_VERSION/priv/bin \
     && cp -r /ejabberd/sql lib/ejabberd-*/priv
 
 # Runtime container

ecs/README.md

@@ -130,6 +130,31 @@ You can open a live debug Erlang console attached to a running container:
 docker exec -it ejabberd bin/ejabberdctl debug
 ```
 
+### CAPTCHA
+
+ejabberd includes two example CAPTCHA scripts.
+If you want to use any of them, first install some additional required libraries:
+
+```bash
+docker exec --user root ejabberd apk add imagemagick ghostscript-fonts bash
+```
+
+Now update your ejabberd configuration file, for example:
+```bash
+docker exec -it ejabberd vi conf/ejabberd.yml
+```
+
+and add the required options:
+```
+captcha_cmd: /home/ejabberd/lib/ejabberd-21.1.0/priv/bin/captcha.sh
+captcha_url: https://localhost:5443/captcha
+```
+
+Finally, reload the configuration file or restart the container:
+```bash
+docker exec ejabberd bin/ejabberdctl reload_config
+```
+
 ## Docker image advanced configuration
 
 ### Ports