feat: add supercronic to allow running background jobs

docker/docker-entrypoint.sh

@@ -157,6 +157,11 @@ if [[ -n "$PAPERLESS_OCR_LANGUAGES" ]]; then
 	install_languages "$PAPERLESS_OCR_LANGUAGES"
 fi
 
+touch /etc/cron.d/export.cron
+if [[ -n "$PAPERLESS_EXPORT_CRON" ]]; then
+	echo "$PAPERLESS_EXPORT_CRON document_exporter /usr/src/paperless/export" > /etc/cron.d/export.cron
+fi
+
 initialize
 
 if [[ "$1" != "/"* ]]; then

docker/supervisord.conf

@@ -17,6 +17,16 @@ stderr_logfile=/dev/stderr
 stderr_logfile_maxbytes=0
 environment = HOME="/usr/src/paperless",USER="paperless"
 
+[program:export]
+command=/usr/local/bin/supercronic /etc/cron.d/export.cron
+user=paperless
+startsecs=0
+priority=2
+stdout_logfile=/dev/stdout
+stdout_logfile_maxbytes=0
+stderr_logfile=/dev/stderr
+stderr_logfile_maxbytes=0
+
 [program:consumer]
 command=python3 manage.py document_consumer
 user=paperless