Added docker compose file with customisation from a .env file.

.env-example

@@ -0,0 +1,58 @@
+#
+# DOCKER COMPOSER CUSTOMIZATION
+#
+
+# Exim version needs to be the correct one for the required Alpine version
+ALPINE_VERSION=3.7
+EXIM_VERSION=4.89.1-r0
+
+# Useful to build the docker image from other path
+EXIM_IMAGE_BUILD_CONTEXT=.
+
+# Builds a local docker image with the whatsoever name we want
+# The EXIM_VERSION will be auto appended to the name:
+#   bambucha/exim-relay-local:4.89.1-r0
+EXIM_IMAGE=bambucha/exim-relay-local
+
+# Default port map is 25:25 but we can override it at any time as suit us
+EXIM_PORT_MAP=2525:25
+
+# By default a native docker volume is used with name smpt-dkim mapping to
+#  container dir /dkim.
+#
+# Docker volumes are suitable for heavy workloads, thus a normal host volume is
+#  the preferred approach for that scenarios.
+#
+# To use a host volume like /home/username/.exim/storage/dkim we need to create
+#  it with:
+#   $ mkdir -p /home/username/.exim/storage/dkim
+#   $ sudo chown 100:101 /home/username/.exim/storage/dkim
+#
+# The use of UID:GID as 100:101 is to match the ones used by the exim user on
+#  the container.
+#
+# Now use it just uncomment the below line and replace username with your host user.
+#DKIM_VOLUME=/home/username/.exim/storage/dkim
+
+# So if we have a domain like example.com we want to set this to:
+HOSTNAME=mail.example.com
+
+
+#
+# DOCKER CONTAINER ENVIRONMENT
+#
+
+# REQUIRED
+DKIM_DOMAINS=example.com
+
+# Custimize here the ips or range of ips from where Exim is allowed to relay.
+RELAY_FROM_HOSTS=10.0.0.0/8:172.16.0.0/12
+
+# Customize the size used by OpenSSL to generate the DKIM key
+DKIM_KEY_SIZE=2048
+
+# Customize here the the headers to be used in the DKIM signature.
+DKIM_SIGN_HEADERS=Date:From:To:Subject:Message-ID
+
+# https://www.emailarchitect.net/domainkeys/doc/html/selector.htm
+DKIM_SELECTOR=dkim

.gitignore

@@ -0,0 +1 @@
+.env

Dockerfile

@@ -1,20 +1,29 @@
-FROM alpine:3.6
+ARG ALPINE_VERSION=3.7
+
+FROM alpine:$ALPINE_VERSION
 MAINTAINER Dmitry Prazdnichnov <[email protected]>
 
-ARG VERSION=4.89-r5
+ARG EXIM_VERSION=4.89.1-r0
+
+ARG DKIM_DOMAINS=domain.tld
+ARG RELAY_FROM_HOSTS=10.0.0.0/8:172.16.0.0/12:192.168.0.0/16
+ARG DKIM_KEY_SIZE=1024
+ARG DKIM_SELECTOR=dkim
+ARG DKIM_SIGN_HEADERS=Date:From:To:Subject:Message-ID
 
-LABEL org.label-schema.version=$VERSION \
+LABEL org.label-schema.version=${EXIM_VERSION} \
       org.label-schema.vcs-url=https://github.com/bambocher/docker-exim-relay \
       org.label-schema.license=MIT \
       org.label-schema.schema-version=1.0
 
-ENV RELAY_FROM_HOSTS=10.0.0.0/8:172.16.0.0/12:192.168.0.0/16 \
-    DKIM_KEY_SIZE=1024 \
-    DKIM_SELECTOR=dkim \
-    DKIM_SIGN_HEADERS=Date:From:To:Subject:Message-ID
+ENV RELAY_FROM_HOSTS=${RELAY_FROM_HOSTS} \
+    DKIM_DOMAINS=${DKIM_DOMAINS} \
+    DKIM_KEY_SIZE=${DKIM_KEY_SIZE} \
+    DKIM_SELECTOR=${DKIM_SELECTOR} \
+    DKIM_SIGN_HEADERS=${DKIM_SIGN_HEADERS}
 
-RUN apk --no-cache add exim=$VERSION libcap openssl \
-    && mkdir /dkim /var/log/exim /usr/lib/exim /var/spool/exim \
+RUN apk --no-cache add exim=${EXIM_VERSION} libcap openssl \
+    && mkdir -p /dkim /var/log/exim /usr/lib/exim /var/spool/exim \
     && ln -s /dev/stdout /var/log/exim/main \
     && ln -s /dev/stderr /var/log/exim/panic \
     && ln -s /dev/stderr /var/log/exim/reject \

README.md

@@ -9,13 +9,13 @@
 Create docker volume for dkim keys:
 
 ```shell
-docker volume create --name=smtp-dkim
+sudo docker volume create --name=smtp-dkim
 ```
 
 Create docker container:
 
 ```shell
-docker run \
+sudo docker run \
     -d \
     --name smtp \
     --restart=always \
@@ -29,27 +29,41 @@ docker run \
 
 ## [Docker Compose](https://docs.docker.com/compose/compose-file)
 
-```yml
-version: "2"
-services:
-  smtp:
-    restart: always
-    image: bambucha/exim-relay
-    user: exim
-    ports:
-      - "25:25"
-    volumes:
-      - smtp-dkim:/dkim
-    hostname: mail.example.com
-    environment:
-      - RELAY_FROM_HOSTS=10.0.0.0/8:172.16.0.0/12:192.168.0.0/16
-      - DKIM_KEY_SIZE=1024
-      - DKIM_SELECTOR=dkim
-      - DKIM_SIGN_HEADERS=Date:From:To:Subject:Message-ID
-      - DKIM_DOMAINS=example.com
-volumes:
-  smtp-dkim:
-    driver: local
+Please rename `.env-example` to `.env` in order to customize how to build the
+ image and containers to run Exim from Docker.
+
+The `.env` file contains comments explaining how each parameter in the
+ `docker-compose.yml` can be overridden.
+
+
+#### Run Exim on the background
+
+```shell
+sudo docker-compose up -d smtp
+```
+
+#### Run Exim attached to the Shell
+
+```shell
+sudo docker-compose up smtp
+```
+
+#### Destroy the running Exim container
+
+```
+sudo docker-compose down
+```
+
+#### Access the Shell of the running container
+
+```shell
+sudo docker-compose exec smtp /bin/sh
+```
+
+#### Access the Shell without having a container running
+
+```shell
+sudo docker-compose run -u root --entrypoint=/bin/sh --rm smtp
 ```
 
 ## Reverse PTR
@@ -73,13 +87,13 @@ example.com. 300 IN TXT "v=spf1 a mx -all"
 Get dkim public key with docker exec:
 
 ```shell
-docker exec -it smtp cat /dkim/example.com.pub
+sudo docker exec -it smtp cat /dkim/example.com.pub
 ```
 
 or get dkim public key with docker-compose exec:
 
 ```shell
-docker-compose exec smtp cat /dkim/example.com.pub
+sudo docker-compose exec smtp cat /dkim/example.com.pub
 ```
 
 or get dkim public key from docker volume:
@@ -99,25 +113,25 @@ dkim._domainkey.example.com. 300 IN TXT "v=DKIM1; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GN
 Print a count of the messages in the queue:
 
 ```shell
-docker exec -it smtp exim -bpc
+sudo docker exec -it smtp exim -bpc
 ```
 
 Print a listing of the messages in the queue (time queued, size, message-id, sender, recipient):
 
 ```shell
-docker exec -it smtp exim -bp
+sudo docker exec -it smtp exim -bp
 ```
 
 Remove all frozen messages:
 
 ```shell
-docker exec -it smtp exim -bpu | grep frozen | awk {'print $3'} | xargs exim -Mrm
+sudo docker exec -it smtp exim -bpu | grep frozen | awk {'print $3'} | xargs exim -Mrm
 ```
 
 Test how exim will route a given address:
 
 ```shell
-docker exec -it smtp exim -bt [email protected]
+sudo docker exec -it smtp exim -bt [email protected]
 ```
 
 ```
@@ -133,31 +147,31 @@ [email protected]
 Display all of Exim's configuration settings:
 
 ```shell
-docker exec -it smtp exim -bP
+sudo docker exec -it smtp exim -bP
 ```
 
 View a message's headers:
 
 ```shell
-docker exec -it smtp exim -Mvh <message-id>
+sudo docker exec -it smtp exim -Mvh <message-id>
 ```
 
 View a message's body:
 
 ```shell
-docker exec -it smtp exim -Mvb <message-id>
+sudo docker exec -it smtp exim -Mvb <message-id>
 ```
 
 View a message's logs:
 
 ```shell
-docker exec -it smtp exim -Mar <message-id>
+sudo docker exec -it smtp exim -Mar <message-id>
 ```
 
 Remove a message from the queue:
 
 ```shell
-docker exec -it smtp exim -Mrm <message-id> [ <message-id> ... ]
+sudo docker exec -it smtp exim -Mrm <message-id> [ <message-id> ... ]
 ```
 
 Send a message:

docker-compose.yml

@@ -0,0 +1,26 @@
+version: "2.1"
+
+services:
+  smtp:
+    restart: always
+    build:
+      context: ${EXIM_IMAGE_BUILD_CONTEXT:-.}
+      args:
+        ALPINE_VERSION: ${ALPINE_VERSION:-3.7}
+        EXIM_VERSION: ${EXIM_VERSION:-4.90}
+    image: ${EXIM_IMAGE:-bambucha/exim-relay}:${EXIM_VERSION:-4.90}
+    ports:
+      - ${EXIM_PORT_MAP:-25:25}
+    volumes:
+      - ${DKIM_VOLUME:-smtp-dkim}:/dkim
+    hostname: ${HOSTNAME:-mail.domain.tld}
+    environment:
+      DKIM_DOMAINS: ${DKIM_DOMAINS:-domain.tld}
+      RELAY_FROM_HOSTS: ${RELAY_FROM_HOSTS:-10.0.0.0/8:172.16.0.0/12:192.168.0.0/16}
+      DKIM_KEY_SIZE: ${DKIM_KEY_SIZE:-1024}
+      DKIM_SELECTOR: ${DKIM_SELECTOR:-dkim}
+      DKIM_SIGN_HEADERS: ${DKIM_SIGN_HEADERS:-Date:From:To:Subject:Message-ID}
+
+volumes:
+  smtp-dkim:
+    driver: local