Update dockerfile

dockerfile

@@ -1,20 +1,35 @@
 FROM ubuntu:22.04
 
+# set non-interactive TERM for docker
 ENV DEBIAN_FRONTEND=noninteractive
 
-RUN apt-get update && apt-get install -y \
-    libltdl7 \
-    libodbc2 \
-    libwrap0 \
-    ldap-utils \
-    libldap-common \
-    libldap-dev \
-    libldap-2.5-0 \
-    libldap2-dev \
-    slapd \
-    slapd-contrib \
-    slapi-dev \
-    #other utilities \
-    vim-common \
-    && rm -rf /var/lib/apt/lists/*
+# install slapd and ldap-utils
+RUN apt-get update && apt-get install -y slapd ldap-utils vim mc && apt-get clean
 
+# preconfigure slapd installation without using systemd
+RUN echo "slapd slapd/password1 password admin" | debconf-set-selections && \
+    echo "slapd slapd/password2 password admin" | debconf-set-selections && \
+    echo "slapd slapd/domain string example.com" | debconf-set-selections && \
+    echo "slapd slapd/no_configuration boolean false" | debconf-set-selections && \
+    echo "slapd slapd/purge_database boolean true" | debconf-set-selections && \
+    echo "slapd slapd/move_old_database boolean true" | debconf-set-selections
+
+# make use of debconf-set-selections
+RUN dpkg-reconfigure -f noninteractive slapd
+
+# open up LDAP simple port
+EXPOSE 389
+
+# set salvable volumes for LDAP data, configuration
+VOLUME ["/var/lib/ldap", "/etc/ldap/slapd.d"]
+
+# set correct permissions for openldap user
+RUN chown -R openldap:openldap /var/lib/ldap /etc/ldap/slapd.d
+
+### optional use ###
+# start slapd
+#CMD ["slapd", "-h", "ldap:/// ldapi:///", "-g", "openldap", "-u", "openldap", "-F", "/etc/ldap/slapd.d"]
+#
+# set entrypoint
+#ENTRYPOINT ["/entrypoint.sh"]
+#CMD ["bash"]