# docker-compose backup
簡易紀錄一下如何備份docker volum

docker-compose.yml

version: "3.7"

networks:
    test-backend:
  
services:
    postgres:
        image: docker.pkg.github.com/gamelab-hrm/postgres/postgres:0.0.1
        expose:
            - 5431
        ports:
            - 127.0.0.1:5431:5432
        networks:
            - test-backend
        volumes:
            - test-data2:/var/lib/postgresql/data        

volumes:
    test-data2:
    some_volume:
        external: true 

### backup tool
https://github.com/loomchild/volume-backup
* **Backup to standard output**
> 將docker volume 備份成tar檔的格式
<<VOLUME NAME>>: 你想備份的volume的name
<<BACKUP FILENAME>>: 備份後的壓縮檔名稱

docker run -v <<VOLUME NAME>>:/volume --rm --log-driver none loomchild/volume-backup backup - > <<BACKUP FILENAME>>.tar.bz2

* **Restore from standard input**
> 將tar檔轉換成docker volume的格式
<<BACKUP FILENAME>>: 壓縮檔來源名稱
<<VOLUME NAME>>: restore後的volume名稱

cat <<BACKUP FILENAME>>.tar.bz2 | docker run -i -v <<VOLUME NAME>>:/volume --rm loomchild/volume-backup restore -