imap-download: add example fetchmail rc file

README.md

@@ -85,6 +85,7 @@ UID     | GID	| Container				| Notes
 95		| 95	| shiori				| Shiori bookmark system, built from source
 999 	| 994	| certbot				| The same user & group as fabio, because file permissions
 2100    | 2100  | redis                 | 
+10000   | 10000 | imap-download         | Uses fetchmail to download emails and extract attachments
 
 ## Development Notes
 

images/imap-download/Dockerfile

@@ -0,0 +1,29 @@
+ARG REPO_LOCATION
+# ARG BASE_VERSION
+
+FROM ${REPO_LOCATION}minideb
+
+RUN install_packages ca-certificates fetchmail procmail inotify-tools mpack
+RUN mkdir /srv/home \
+	&& ln -s /mnt/fetchmailrc /srv/home/.fetchmailrc \
+	&& mkdir /tmp/maildir
+
+ENV HOME /srv/home
+
+COPY ./procmail.conf /srv/procmail.conf
+COPY ./run.sh /srv/run.sh
+
+VOLUME /mnt/fetchmailrc
+VOLUME /mnt/output
+
+# Example fetchmailrc file: 
+#
+# poll starbeamrainbowlabs.com protocol IMAP
+#	user "user@example.com" with pass "PASSWORD_HERE"
+#	idle
+#	ssl
+
+
+USER 10000:10000
+
+ENTRYPOINT [ "/srv/run.sh" ]

images/imap-download/procmail.conf

@@ -0,0 +1,5 @@
+CORRECTHOME=/tmp/maildir
+MAILDIR=$CORRECTHOME/
+
+:0
+Mail/

images/imap-download/run.sh

@@ -0,0 +1,48 @@
+#!/usr/bin/env bash
+
+temp_dir="$(mktemp --tmpdir -d "imap-download-XXXXXXX")";
+on_exit() {
+	rm -rf "${temp_dir}";
+}
+trap on_exit EXIT;
+
+do_fetchmail() {
+	fetchmail --mda "/usr/bin/procmail -m /srv/procmail.conf";
+}
+
+log_msg() {
+	echo "$(date -u +"%Y-%m-%d %H:%M:%S") imap-download: $*";
+}
+
+dir_newmail="/tmp/maildir/Mail/new";
+target_dir="/mnt/output";
+
+do_attachments() {
+	while :; do # : = infinite loop
+		# Wait for an update
+		# inotifywait's non-0 exit code forces an exit for some reason :-/
+		inotifywait -qr --event create --format '%:e %f' "${dir_newmail}";
+		
+		while read -r filename; do
+			log_msg "Processing email ${filename}";
+			
+			# Move the email to a temporary directory for processing
+			mv "${filename}" "${temp_dir}";
+			
+			# Unpack the attachments
+			munpack -C "${temp_dir}" "${filename}";
+			# Delete the original email file and any description files
+			rm "${filename}";
+			find "${temp_dir}" -iname '*.desc' -delete;
+			
+			# Move the attachment files to the output directory
+			while read -r attachment; do
+				log_msg "Extracted attachment ${attachment}";
+				mv "${attachment}" "${target_dir}";
+			done < <(find "${temp_dir}" -type f);
+		done < <(find "${dir_newmail}" -type f);
+	done
+}
+
+do_fetchmail &
+do_attachments

images/imap-download/type.txt

@@ -0,0 +1 @@
+docker