From 3db704557a11406d749afef37dd9e134b1bd5740 Mon Sep 17 00:00:00 2001
From: Richard Scorer <richard@scorer.org>
Date: Thu, 3 Sep 2020 14:30:21 +0100
Subject: [PATCH] Add ability to set gzip compression level

---
 README.md | 3 +++
 backup.sh | 3 ++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 4ffcfed..f44fe2c 100644
--- a/README.md
+++ b/README.md
@@ -28,6 +28,7 @@ docker container run -d \
 - `INIT_BACKUP`: If set, create a backup when the container starts.
 - `INIT_RESTORE_LATEST`: If set, restores latest backup.
 - `TIMEOUT`: Wait a given number of seconds for the database to be ready and make the first backup, `10s` by default. After that time, the initial attempt for backup gives up and only the Cron job will try to make a backup.
+- `GZIP_LEVEL`: Specify the level of gzip compression from 1 (quickest, least compressed) to 9 (slowest, most compressed), default is 6.
 
 If you want to make this image the perfect companion of your MySQL container, use [docker-compose](https://docs.docker.com/compose/). You can add more services that will be able to connect to the MySQL image using the name `my_mariadb`, note that you only expose the port `3306` internally to the servers and not to the host:
 
@@ -62,6 +63,8 @@ services:
       - INIT_BACKUP=0
       # Every day at 03:00
       - CRON_TIME=0 3 * * *
+      # Make it small
+      - GZIP_LEVEL=9
     restart: unless-stopped
 
 volumes:
diff --git a/backup.sh b/backup.sh
index 30314da..2a01db6 100755
--- a/backup.sh
+++ b/backup.sh
@@ -1,6 +1,7 @@
 #!/bin/bash
 [ -z "${MYSQL_USER}" ] && { echo "=> MYSQL_USER cannot be empty" && exit 1; }
 [ -z "${MYSQL_PASS:=$MYSQL_PASSWORD}" ] && { echo "=> MYSQL_PASS cannot be empty" && exit 1; }
+[ -z "${GZIP_LEVEL}" ] && { GZIP_LEVEL=6; }
 
 DATE=$(date +%Y%m%d%H%M)
 echo "=> Backup started at $(date "+%Y-%m-%d %H:%M:%S")"
@@ -15,7 +16,7 @@ do
     LATEST=/backup/latest.$db.sql.gz
     if mysqldump -h "$MYSQL_HOST" -P "$MYSQL_PORT" -u "$MYSQL_USER" -p"$MYSQL_PASS" --databases "$db" $MYSQLDUMP_OPTS > "$FILENAME"
     then
-      gzip -f "$FILENAME"
+      gzip "-$GZIP_LEVEL" -f "$FILENAME"
       echo "==> Creating symlink to latest backup: $(basename "$FILENAME".gz)"
       rm "$LATEST" 2> /dev/null
       cd /backup && ln -s $(basename "$FILENAME".gz) $(basename "$LATEST") && cd -