Delete strategy moved to new file, as could custom

Dockerfile

@@ -32,10 +32,10 @@ ENV CRON_TIME="0 3 * * sun" \
     TIMEOUT="10s" \
     MYSQLDUMP_OPTS="--quick"
 
-COPY ["run.sh", "backup.sh", "restore.sh", "/"]
+COPY ["run.sh", "backup.sh", "restore.sh", "/delete.sh", "/"]
 RUN mkdir /backup && \
     chmod 777 /backup && \ 
-    chmod 755 /run.sh /backup.sh /restore.sh && \
+    chmod 755 /run.sh /backup.sh /restore.sh /delete.sh && \
     touch /mysql_backup.log && \
     chmod 666 /mysql_backup.log
 

backup.sh

@@ -46,13 +46,8 @@ do
       cd /backup || exit && ln -s "$BASENAME" "$(basename "$LATEST")"
       if [ -n "$MAX_BACKUPS" ]
       then
-        while [ "$(find /backup -maxdepth 1 -name "*.$db.sql$EXT" -type f | wc -l)" -gt "$MAX_BACKUPS" ]
-        do
-          TARGET=$(find /backup -maxdepth 1 -name "*.$db.sql$EXT" -type f | sort | head -n 1)
-          echo "==> Max number of ($MAX_BACKUPS) backups reached. Deleting ${TARGET} ..."
-          rm -rf "${TARGET}"
-          echo "==> Backup ${TARGET} deleted"
-        done
+        # Execute the delete script, delete older backup or other custom delete script
+        /delete.sh $db $EXT
       fi
     else
       rm -rf "$FILENAME"

delete.sh

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+db=$1
+EXT=$2
+
+# This file could be customized to create custom delete strategy
+
+while [ "$(find /backup -maxdepth 1 -name "*.$db.sql$EXT" -type f | wc -l)" -gt "$MAX_BACKUPS" ]
+do
+  TARGET=$(find /backup -maxdepth 1 -name "*.$db.sql$EXT" -type f | sort | head -n 1)
+  echo "==> Max number of ($MAX_BACKUPS) backups reached. Deleting ${TARGET} ..."
+  rm -rf "${TARGET}"
+  echo "==> Backup ${TARGET} deleted"
+done