update alpine base image to 3.14

Allow for making container stop filter configurable

Dockerfile

@@ -1,7 +1,7 @@
 # Copyright 2021 - Offen Authors <hioffen@posteo.de>
 # SPDX-License-Identifier: MIT
 
-FROM alpine:3.13
+FROM alpine:3.14
 
 WORKDIR /root
 

README.md

@@ -53,6 +53,16 @@ AWS_S3_BUCKET_NAME="<xxx>"
 
 # GPG_PASSPHRASE="<xxx>"
 
+########### STOPPING CONTAINERS DURING BACKUP
+
+# Containers can be stopped by applying a
+# `docker-volume-backup.stop-during-backup` label. By default, all containers
+# that are labeled with `true` will be stopped. If you need more fine grained
+# control (e.g. when running multiple containers based on this image), you can
+# override this default by specifying a different value here.
+
+# BACKUP_STOP_CONTAINER_LABEL="service1"
+
 ########### MINIO CLIENT CONFIGURATION
 
 # Pass these additional flags to all MinIO client `mc` invocations.

src/backup.sh

@@ -19,7 +19,7 @@ if [ -S "$DOCKER_SOCK" ]; then
   TEMPFILE="$(mktemp)"
   docker ps \
     --format "{{.ID}}" \
-    --filter "label=docker-volume-backup.stop-during-backup=true" \
+    --filter "label=docker-volume-backup.stop-during-backup=$BACKUP_STOP_CONTAINER_LABEL" \
     > "$TEMPFILE"
   CONTAINERS_TO_STOP="$(cat $TEMPFILE | tr '\n' ' ')"
   CONTAINERS_TO_STOP_TOTAL="$(cat $TEMPFILE | wc -l)"

src/entrypoint.sh

@@ -22,6 +22,8 @@ AWS_ENDPOINT="${AWS_ENDPOINT:-s3.amazonaws.com}"
 
 GPG_PASSPHRASE="${GPG_PASSPHRASE:-}"
 
+BACKUP_STOP_CONTAINER_LABEL="${BACKUP_STOP_CONTAINER_LABEL:-true}"
+
 MC_GLOBAL_OPTIONS="${MC_GLOBAL_OPTIONS:-}"
 EOF
 chmod a+x env.sh