Don't build a new container for ldap, pass the variables via docker-compose.

example/ldap/Dockerfile

@@ -1,9 +0,0 @@
-FROM clems4ever/openldap
-
-ENV SLAPD_ORGANISATION=MyCompany
-ENV SLAPD_DOMAIN=example.com
-ENV SLAPD_PASSWORD=password
-ENV SLAPD_CONFIG_PASSWORD=password
-ENV SLAPD_ADDITIONAL_MODULES=memberof
-ENV SLAPD_ADDITIONAL_SCHEMAS=openldap
-ENV SLAPD_FORCE_RECONFIGURE=true

example/ldap/docker-compose.yml

@@ -1,7 +1,15 @@
 version: '2'
 services:
   openldap:
-    build: ./example/ldap
+    image: clems4ever/openldap
+    environment:
+      - SLAPD_ORGANISATION=MyCompany
+      - SLAPD_DOMAIN=example.com
+      - SLAPD_PASSWORD=password
+      - SLAPD_CONFIG_PASSWORD=password
+      - SLAPD_ADDITIONAL_MODULES=memberof
+      - SLAPD_ADDITIONAL_SCHEMAS=openldap
+      - SLAPD_FORCE_RECONFIGURE=true
     volumes:
       - ./example/ldap/base.ldif:/etc/ldap.dist/prepopulate/base.ldif
       - ./example/ldap/access.rules:/etc/ldap.dist/prepopulate/access.rules