Articles

These are currently random notes and are not much help to anybody yet. They will get tidied as I add to the page.

Docker Swarm

Docker swarm secrets

From inside a docker swarm manager node, there are two ways of creating a secret.

Using a string value:

printf <your_secret_value> | docker secret create your_secret_key -

Using a file path:

docker secret create your_secret_key ./your_secret_value.json

Docker swarm secrets are saved, encrypted, and are accessible to containers via a filepath:

/run/secrets/your_secret_key.

Posts to digest

https://www.bretfisher.com/docker-swarm-firewall-ports/

https://www.bretfisher.com/docker/

https://www.digitalocean.com/community/tutorials/how-to-set-up-laravel-nginx-and-mysql-with-docker-compose

After getting half-way through a Docker Mastery series on Udemy, I decided I would like to move my WordPress website, this one, to using a 3-node swarm.

After a few days of editing and re-arranging my docker-compose.yml file (the local dev configuration file that can also be used for starting up a swarm since compose version 3.3) I have decided to just keep my website hosted on its single regular server. (Although I had already moved the database to its own dedicated server).

Despite the fact that I haven’t actually managed to move over to using a swarm (and to be honest it isn’t even needed for me) I have managed to dive into a bunch of concepts around Docker and its Swarm component and feel that I have added a few new things to me dev toolkit.

I think I will definitely be putting together a little demo in a swarm across three separate servers. But for now I will keep my website settled as it is. 😀

What I have learned – or rather reminded myself of, whilst sat in at home during this damn isolation, is that it is important to keep looking into complimentary technologies around my everyday development skill set.

This is a quick brain dump for myself to remember how I set up Laravel with Docker. Hopefully it can help others out also.

I tried to avoid Docker for the longest time due to the ease of just running php artisan serve. However, when you have some dependancies that your site will rely on, Docker can be helpful — especially when having multiple developers — in getting up and running with the whole codebase easier.

This post assumes you have setup a basic Laravel project on a Linux computer, and have both Docker and Docker Compose installed locally.

What will this project use?

This is only a basic example to get up and running with the following dependancies. You can add more items to your docker-compose.yml file as you need to.

Note: whatever you choose to name each extra service in your docker-compose.yml file, use its key as the reference point in your .env file.

• The main site codebase
• A MySQL database
• an NGINX webserver
• PHP

docker-compose.yml

Have a file in the project root, named ``docker-compose.yml`

version: "3.3"

services:
  mysql:
    image: mysql:8.0
    restart: on-failure
    env_file:
      - .env
    environment:
      MYSQL_ROOT_PASSWORD: ${MYSQL_ROOT_PASSWORD}
      MYSQL_DATABASE: ${MYSQL_DATABASE}
  nginx:
    image: nginx:1.15.3-alpine
    restart: on-failure
    volumes:
      - './public/:/usr/src/app'
      - './docker/nginx/default.conf:/etc/nginx/conf.d/default.conf:ro'
    ports:
      - 80:80
    env_file:
      - .env
    depends_on:
      - php
  php:
    build:
      context: .
      dockerfile: './docker/php/Dockerfile'
    restart: on-failure
    env_file:
      - .env
    user: ${LOCAL_USER}

Dockerfile

Have a Dockerfile located here: ./docker/php/Dockerfile. I keep it in a separate folder for tidiness.

# ./docker/php/Dockerfile
FROM php:7.2-fpm

RUN docker-php-ext-install pdo_mysql

RUN pecl install apcu-5.1.8
RUN docker-php-ext-enable apcu

RUN php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');" \
    && php -r "if (hash_file('SHA384', 'composer-setup.php') === '48e3236262b34d30969dca3c37281b3b4bbe3221bda826ac6a9a62d6444cdb0dcd0615698a5cbe587c3f0fe57a54d8f5') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;" \
    && php composer-setup.php --filename=composer \
    && php -r "unlink('composer-setup.php');" \
    && mv composer /usr/local/bin/composer

WORKDIR /usr/src/app

COPY ./ /usr/src/app

RUN PATH=$PATH:/usr/src/app/vendor/bin:bin

default.conf

Have a default.conf file for the project’s nginx container saved here: ./docker/nginx/default.conf

# ./docker/nginx/default.conf
server {
 server_name ~.*;

 location / {
     root /usr/src/app;

     try_files $uri /index.php$is_args$args;
 }

 location ~ ^/index\.php(/|$) {
     client_max_body_size 50m;

     fastcgi_pass php:9000;
     fastcgi_buffers 16 16k;
     fastcgi_buffer_size 32k;
     include fastcgi_params;
     fastcgi_param SCRIPT_FILENAME /usr/src/app/public/index.php;
 }

 error_log /dev/stderr debug;
 access_log /dev/stdout;
}

Add the necessary variables to your .env file

There are some variables used in the docker-compose.yml file that need to be added to the .env file. These could be added directly, but this makes it more straightforward for other developers to customise their own setup.

MYSQL_ROOT_PASSWORD=root
MYSQL_DATABASE=example
LOCAL_USER=1000:1000

The MYSQL_ROOT_PASSWORD and MYSQL_DATABASE are self-explanatory, but theLOCAL_USER variable refers to the user id and group id of the currently logged in person on the host machine. This normally defaults to 1000 for both user and group.

If your user and/or group ids happen to be different, just alter the variable value.

Note: find out your own ids by opening your terminal and typing id followed by enter. You should see something like the following:

uid=1000(david) gid=1000(david) groups=1000(david),4(adm),27(sudo),1001(rvm)

uid and gid are the numbers you need, for user and group respectively.

Run it

Run the following two commands separately then once they are finished head to http:localhost to view the running code.

Note: This setup uses port 80 so you may need to disable any local nginx / apache that may be running currently.

docker-compose build
docker-compose up -d

Any mistakes or issues, just email me.

Thanks for reading.