Docker Volume Persistence

Question

I am trying to learn Docker. I have installed Docker Desktop on my Windows10 Pro computer.

I started with getting a PHP, MySQL website up and running using Docker.

My docker-compose.yml looks like

version: "3.8"
services:
    www:
        build: .
        ports: 
            - "80:80"
        volumes:
            - ./www:/var/www/html            
        links:
            - db
        networks:
            - default
    db:
        image: mysql:8.0
        ports: 
            - "3306:3306"
        command: --default-authentication-plugin=mysql_native_password
        environment:
            MYSQL_DATABASE: myDb
            MYSQL_USER: user
            MYSQL_PASSWORD: test
            MYSQL_ROOT_PASSWORD: test 
        volumes:
            - ./dump:/docker-entrypoint-initdb.d
            - ./conf:/etc/mysql/conf.d
            - persistent:/var/lib/mysql
        networks:
            - default
    phpmyadmin:
        image: phpmyadmin/phpmyadmin
        links: 
            - db:db
        ports:
            - 8000:80
        environment:
            MYSQL_USER: user
            MYSQL_PASSWORD: test
            MYSQL_ROOT_PASSWORD: test 
volumes:
    persistent:

and the DockerFile looks like

FROM php:7.3-apache 
RUN docker-php-ext-install mysqli
RUN apt-get update \
    && apt-get install -y libzip-dev \
    && apt-get install -y wget \
    && apt-get install -y zlib1g-dev \
    && rm -rf /var/lib/apt/lists/* \
    && docker-php-ext-install zip

I have a www folder with an index.php.

When I run

docker-compose up -d

I have the PHP, mySQL site up and running correctly and I can access the index.php with expected results.

So far so good.

Now, I want to change the Dockerfile to setup a php forum website (phpbb) - so I have updated my Dockerfile as follows:

FROM php:7.3-apache 
RUN docker-php-ext-install mysqli
RUN apt-get update \
    && apt-get install -y libzip-dev \
    && apt-get install -y wget \
    && apt-get install -y zlib1g-dev \
    && rm -rf /var/lib/apt/lists/* \
    && docker-php-ext-install zip

WORKDIR /var/www/html

RUN wget https://download.phpbb.com/pub/release/3.3/3.3.0/phpBB-3.3.0.tar.bz2 \
&& tar -xvjf phpBB-3.3.0.tar.bz2
&& ls -l

When I run

docker-compose build --no-cache

I can see the expected results - i.e, the "ls" command shows all the expected phpBB files in /var/www/html

However, when I run

docker-compose up -d

My container only has the index.php in the /var/www/html (the index.php from the www folder). None of the phpBB files are there.

What am I doing wrong?

score 0 · Accepted Answer · answered Jul 19 '20 at 14:47

0

The files are there but you are hiding them by your bind mount.

You are bind mounting ./www into the same directory (/var/www/html) which will hide its contents.

here:

www:
  ...
  volumes:
    - ./www:/var/www/html

When you are building the image, you correctly see the files but once you run docker-compose the bind mount is created and it hides those files.

answered Jul 19 '20 at 14:47

Matus Dubrava

13,637
2
38
54

Thanks. So what should I be doing instead? – Jason Ambrose Jul 19 '20 at 14:50
That depends on what you want to achieve. Don't use bind mount or mount it to another directory or install the files somewhere else. You need to figure out your directory structure based on your needs, there is no one solution that fits all needs. – Matus Dubrava Jul 19 '20 at 14:53

Docker Volume Persistence

1 Answers1