Add custom entrypoint to generate the configuration

Dockerfile

@@ -16,7 +16,7 @@ LABEL maintainer "Abiola Ibrahim <[email protected]>"
 
 LABEL caddy_version="0.10.10"
 
-RUN apk add --no-cache openssh-client git
+RUN apk add --no-cache openssh-client git bash
 
 # install caddy
 COPY --from=builder /install/caddy /usr/bin/caddy
@@ -26,12 +26,12 @@ RUN /usr/bin/caddy -version
 RUN /usr/bin/caddy -plugins
 
 EXPOSE 80 443 2015
-VOLUME /root/.caddy /srv
+VOLUME /root/.caddy /srv /etc/caddy
 WORKDIR /srv
 
-COPY Caddyfile /etc/Caddyfile
 COPY index.html /srv/index.html
+COPY docker-entrypoint.sh /
+COPY docker-entrypoint.d /docker-entrypoint.d/
 
-ENTRYPOINT ["/usr/bin/caddy"]
-CMD ["--conf", "/etc/Caddyfile", "--log", "stdout"]
-
+ENTRYPOINT ["/bin/bash", "/docker-entrypoint.sh"]
+CMD ["/usr/bin/caddy", "--conf", "/etc/caddy/Caddyfile", "--log", "stdout"]

README.md

@@ -12,6 +12,57 @@ Check [abiosoft/caddy:builder](https://github.com/abiosoft/caddy-docker/blob/mas
 
 This image is built from [source code](https://github.com/mholt/caddy). As such, it is subject to the project's [Apache 2.0 license](https://github.com/mholt/caddy/blob/baf6db5b570e36ea2fee30d50f879255a5895370/LICENSE.txt), but it neither contains nor is subject to [the EULA for Caddy's official binary distributions](https://github.com/mholt/caddy/blob/545fa844bbd188c1e5bff6926e5c410e695571a0/dist/EULA.txt).
 
+## Proxy Configuration
+
+The default behaviour is the same as previously, the configuration is taken from /etc/Caddyfile.
+
+If Environment Variable `CADDY_GENERATE_CONFIG` is set to `yes` or `true` the configuration file `/etc/caddy/Caddyfile` is autogenerated using a simple template that lookup environment variables.
+
+The templating supports defining multiple hostnames and multiple filters and proxies for each hostname.
+Example environment variables:
+
+```sh
+CADDY_GENERATE_CONFIG=yes
+CADDY_ENTRY0_HOSTNAME=foo.bar.baz
+CADDY_ENTRY0_TLS_MODE=self_signed
+CADDY_ENTRY0_AUTH0_PATH=/
+CADDY_ENTRY0_AUTH0_USERNAME=foo
+CADDY_ENTRY0_AUTH0_PASSWORD=bar
+CADDY_ENTRY0_PROXY0_PATH=/
+CADDY_ENTRY0_PROXY0_DEST='http://localhost:8080'
+CADDY_ENTRY0_FILTER0_PATH=/
+CADDY_ENTRY0_FILTER0_CONTENT_TYPE='text/html.*'
+CADDY_ENTRY0_FILTER0_SEARCH_PATTERN="=\" /"
+CADDY_ENTRY0_FILTER0_REPLACEMENT="=\" /mesos/"
+CADDY_ENTRY0_PROXY0_WEBSOCKET=yes
+CADDY_ENTRY0_PROXY0_WITHOUT="/mesos"
+CADDY_ENTRY0_PROXY0_TRANSPARENT="yes"
+```
+
+Which will create the following configuration::
+```
+foo.bar.baz {
+  filter rule {
+    path /
+    content_type text/html.*
+    search_pattern =" /
+    replacement =" /mesos/
+  }
+  basicauth / foo bar
+  tls self_signed
+  log stdout
+  errors stderr
+  proxy / http://localhost:8080 {
+    without /mesos
+    websocket
+    transparent
+  }
+}
+```
+
+For other definitions use `CADDY_ENTRY1` `CADDY_ENTRY2` etc and for filters and proxies you can also increment the id to have multiple definitions.
+
+Custom configuration can be inserted using `CADDY_ENTRY0_CUSTOM0` and each line will be displayed in order at the bottom of the configuration of the hostname.
 
 ## Getting Started
 

docker-entrypoint.d/00-prelude.conf

@@ -0,0 +1 @@
+## This file was autogenerated by /entrypoint.sh

docker-entrypoint.d/40-listen-points.sh

@@ -0,0 +1,18 @@
+offset=0
+while true; do
+  BASEVAR="CADDY_ENTRY${offset}"
+  HOSTNAME="${BASEVAR}_HOSTNAME"
+  if [ -z ${!HOSTNAME} ]; then
+    break
+  fi
+  echo "${!HOSTNAME} {"
+  for each in $(find /docker-entrypoint.d/40-listen-points/ | sort -n); do
+    case $each in
+      *.part)
+        source $each
+        ;;
+    esac
+  done
+  echo "}"
+  offset=$((offset + 1))
+done

docker-entrypoint.d/40-listen-points/00-prelude.part

@@ -0,0 +1,2 @@
+echo "  log stdout"
+echo "  errors stderr"

docker-entrypoint.d/40-listen-points/20-tls.part

@@ -0,0 +1,7 @@
+TLS_VAR=$"{BASEVAR}_TLS_MODE"
+TLS="${!TLS_VAR}"
+if [ -z "${TLS}" ]; then
+  TLS="self_signed"
+fi
+
+echo "  tls $TLS"

docker-entrypoint.d/40-listen-points/40-filter.part

@@ -0,0 +1,22 @@
+FILTER_MAXBUFFER_SIZE="${BASEVAR}_FILTER_MAXBUFFER_SIZE"
+if [ ! -z "${!FILTER_MAXBUFFER_SIZE}" ]; then
+  echo "  filter max_buffer_size ${!FILTER_MAXBUFFER_SIZE}"
+fi
+
+inneroffset=0
+while true; do
+  FILTER_PATH="${BASEVAR}_FILTER${inneroffset}_PATH"
+  FILTER_CONTENT_TYPE="${BASEVAR}_FILTER${inneroffset}_CONTENT_TYPE"
+  FILTER_SEARCH_PATTERN="${BASEVAR}_FILTER${inneroffset}_SEARCH_PATTERN"
+  FILTER_REPLACEMENT="${BASEVAR}_FILTER${inneroffset}_REPLACEMENT"
+  if [ -z "${!FILTER_PATH}" ] || [ -z "${!FILTER_CONTENT_TYPE}" ] || [ -z "${!FILTER_SEARCH_PATTERN}" ] || [ -z "${!FILTER_REPLACEMENT}" ]; then
+    break
+  fi
+  echo "  filter rule {"
+  echo "    path ${!FILTER_PATH}"
+  echo "    content_type ${!FILTER_CONTENT_TYPE}"
+  echo "    search_pattern ${!FILTER_SEARCH_PATTERN}"
+  echo "    replacement ${!FILTER_REPLACEMENT}"
+  echo "  }"
+  inneroffset=$((inneroffset + 1))
+done

docker-entrypoint.d/40-listen-points/50-authentication.part

@@ -0,0 +1,11 @@
+inneroffset=0
+while true; do
+  USERNAME="${BASEVAR}_AUTH${inneroffset}_USERNAME"
+  HTTP_PATH="${BASEVAR}_AUTH${inneroffset}_PATH"
+  PASSWORD="${BASEVAR}_AUTH${inneroffset}_PASSWORD"
+  if [ -z "${!USERNAME}" ] || [ -z "${!HTTP_PATH}" ] || [ -z "${!PASSWORD}" ]; then
+    break
+  fi
+  echo "  basicauth ${!HTTP_PATH} ${!USERNAME} ${!PASSWORD}"
+  inneroffset=$((inneroffset + 1))
+done

docker-entrypoint.d/40-listen-points/70-proxy.part

@@ -0,0 +1,25 @@
+inneroffset=0
+while true; do
+  PROXY_BASEVAR="${BASEVAR}_PROXY${inneroffset}"
+  PROXY_PATH="${PROXY_BASEVAR}_PATH"
+  PROXY_DEST="${PROXY_BASEVAR}_DEST"
+  if [ -z "${!PROXY_PATH}" ] || [ -z "${!PROXY_DEST}" ]; then
+    break
+  fi
+  echo "  proxy ${!PROXY_PATH} ${!PROXY_DEST} {"
+  WITHOUT="${PROXY_BASEVAR}_WITHOUT"
+  if [ ! -z "${!WITHOUT}" ]; then
+    echo "    without ${!WITHOUT}"
+  fi
+  WEBSOCKET="${PROXY_BASEVAR}_WEBSOCKET"
+  if [ ! -z "${!WEBSOCKET}" ]; then
+    echo "    websocket"
+  fi
+  TRANSPARENT="${PROXY_BASEVAR}_TRANSPARENT"
+  if [ ! -z "${!TRANSPARENT}" ]; then
+    echo "    transparent"
+  fi
+  echo "  }"
+  inneroffset=$((inneroffset + 1))
+done
+

docker-entrypoint.d/40-listen-points/90-custom.part

@@ -0,0 +1,9 @@
+inneroffset=0
+while true; do
+  CUSTOM="${BASEVAR}_CUSTOM${inneroffset}"
+  if [ -z "${!CUSTOM}" ]; then
+    break
+  fi
+  echo "  ${!CUSTOM}"
+  inneroffset=$((inneroffset + 1))
+done

docker-entrypoint.sh

@@ -0,0 +1,23 @@
+#!/bin/bash
+
+rm -f /etc/caddy/Caddyfile
+case $CADDY_GENERATE_CONFIG in
+  yes|true)
+    for each in $(find /docker-entrypoint.d/ | sort -n) ; do
+      case $each in
+        *.sh)
+          source "$each" >> /etc/caddy/Caddyfile
+          ;;
+        *.conf)
+          cat "$each" >> /etc/caddy/Caddyfile
+          ;;
+      esac
+    done
+    ;;
+  *)
+    echo "Using Provided Caddyfile instead of generating it"
+    cp /etc/Caddyfile /etc/caddy/Caddyfile
+    ;;
+esac
+
+exec $@