Merge pull request #1 from mmartinortiz/create-link-to-latest-backup

Create link to latest backup

README.md

@@ -6,32 +6,76 @@ This docker image runs mysqldump to backup your databases periodically using cro
 
 ## Usage:
 
-  docker container run -d \
+```bash
-    --env MYSQL_USER=root \
+docker container run -d \
-    --env MYSQL_PASS=my_password \
+       --env MYSQL_USER=root \
-    --link mysql
+       --env MYSQL_PASS=my_password \
-    --volume /path/to/my/backup/folder:/backup
+       --link mysql
-    fradelg/mysql-cron-backup
+       --volume /path/to/my/backup/folder:/backup
+       fradelg/mysql-cron-backup
+```
 
 ## Variables
 
-    MYSQL_HOST      the host/ip of your mysql database
+- `MYSQL_HOST`: The host/ip of your mysql database.
-    MYSQL_PORT      the port number of your mysql database
+- `MYSQL_PORT`: The port number of your mysql database.
-    MYSQL_USER      the username of your mysql database
+- `MYSQL_USER`: The username of your mysql database.
-    MYSQL_PASS      the password of your mysql database
+- `MYSQL_PASS`: The password of your mysql database.
-    MYSQL_DB        the database name to dump. Default: `--all-databases`
+- `MYSQL_DB`: The database name to dump. Default: `--all-databases`.
-		MYSQLDUMP_OPTS  command line arguments to pass to mysqldump. Example: `--single-transaction`
+- `MYSQLDUMP_OPTS`: Command line arguments to pass to mysqldump. Example: `--single-transaction`.
-    CRON_TIME       the interval of cron job to run mysqldump. `0 0 * * *` by default, which is every day at 00:00
+- `CRON_TIME`: The interval of cron job to run mysqldump. `0 3 * * sun` by default, which is every Sunday at 03:00.
-    MAX_BACKUPS     the number of backups to keep. When reaching the limit, the old backup will be discarded. No limit by default
+- `MAX_BACKUPS`: The number of backups to keep. When reaching the limit, the old backup will be discarded. No limit by default.
-    INIT_BACKUP     if set, create a backup when the container starts
+- `INIT_BACKUP`: If set, create a backup when the container starts.
-    INIT_RESTORE_LATEST if set, restores latest backup
+- `INIT_RESTORE_LATEST`: Ff set, restores latest backup.
+
+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:
+
+```yaml
+version: "2"
+services:
+  mariadb:
+    image: mariadb
+    container_name: my_mariadb
+    expose:
+      - 3306
+    volumes:
+      # If there is not scheme, restore the last created backup (if exists)
+      - ${VOLUME_PATH}/backup/latest.${DATABASE_NAME}.sql.gz:/docker-entrypoint-initdb.d/database.sql.gz
+    environment:
+      - MYSQL_ROOT_PASSWORD=${MARIADB_ROOT_PASSWORD}
+      - MYSQL_DATABASE=${DATABASE_NAME}
+      - MYSQL_USER=${WORDPRESS_DB_USER}
+      - MYSQL_PASSWORD=${WORDPRESS_DB_PASSWORD}
+    restart: unless-stopped
+
+  mysql-cron-backup:
+    image: fradelg/mysql-cron-backup
+    depends_on:
+      - my_mariadb
+    volumes:
+      - ${VOLUME_PATH}/backup:/backup
+    environment:
+      - MYSQL_HOST=my_mariadb
+      - MYSQL_USER=root
+      - MYSQL_PASS=${MARIADB_ROOT_PASSWORD}
+      - MAX_BACKUPS=15
+      - INIT_BACKUP=0
+      # Every day at 03:00
+      - CRON_TIME=* 3 * * *
+    restart: unless-stopped
+
+```
 
 ## Restore from a backup
 
 See the list of backups in your running docker container, just write in your favorite terminal:
 
-    docker container exec backup ls /backup
+```bash
+docker container exec backup ls /backup
+```
 
 To restore a database from a certain backup, simply run:
 
-    docker container exec backup /restore.sh /backup/201708060500.my_db.sql.gz
+```bash
+docker container exec backup /restore.sh /backup/201708060500.my_db.sql.gz
+```

backup.sh

@@ -11,9 +11,12 @@ do
   then
     echo "Dumping database: $db"
     FILENAME=/backup/$DATE.$db.sql
+    LATEST=/backup/latest.$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 "$FILENAME"
+      rm "$LATEST" 2> /dev/null
+      ln -s "$FILENAME" "$LATEST"
     else
       rm -rf "$FILENAME"
     fi
@@ -22,9 +25,9 @@ done
 
 if [ -n "$MAX_BACKUPS" ]
 then
-  while [ "$(find /backup -maxdepth 1 -name "*.sql.gz" | wc -l)" -gt "$MAX_BACKUPS" ]
+  while [ "$(find /backup -maxdepth 1 -name "*.sql.gz" -type f | wc -l)" -gt "$MAX_BACKUPS" ]
   do
-    TARGET=$(find /backup -maxdepth 1 -name "*.sql.gz" | sort | head -n 1)
+    TARGET=$(find /backup -maxdepth 1 -name "*.sql.gz" -type f | sort | head -n 1)
     echo "Backup $TARGET is deleted"
     rm -rf "$TARGET"
   done