Local changes propagate to docker container only when container is restarted

Question

EDIT

I have created a repo for setting up WP with Docker on PHP7.3, latest WordPress on php-fpm and I get the same issue: https://github.com/dingo-d/wordpress-docker

You can check it out to see what could be an issue. My guess is something with PHP-FPM has to be the issue (since restarting that container makes the changes propagate).

---

I have created a WordPress docker local dev environment by following the tutorial I found here .

Basically, all my docker stuff is located in the .docker folder.

I have these files in the .docker folder

|--project-folder
|____.docker
| |____php-fpm
| | |____php.ini
| | |____Dockerfile
| |____nginx
| | |____Dockerfile
| | |____logs
| | | |____error.log
| | | |____access.log
| | |____certs
| | | |____dev.project.com.key
| | | |____dev.project.com.crt
| | |____scripts
| | | |____docker-nginx-entrypoint.sh
| | |____nginx.conf
| |____.dockerignore
| |____.env
| |____docker-compose.yml
| |____.env.example

After trying to set everything up with the self signed SSL certificates, I can log in to https://localhost:8443 (I have some issues with setting the hosts file so that I can go to https://dev.project.com but that's another issue).

The problem is that when I go and change something in my theme, say add a print_r statement that should just print something out, I can see that change in the WP admin only after I restart my WordPress app container. The folders are mapped, and when I change things locally and exec to container, those changes are there immediately (and when I delete them while exec'd in the container they get deleted in my editor immediately).

I've tested if the same thing will happen with a super simple WordPress Docker setup I found online

version: '3'
services:
   db:
     image: mysql:5.7
     volumes:
       - db_data:/var/lib/mysql
     restart: always
     environment:
       MYSQL_ROOT_PASSWORD: password
       MYSQL_DATABASE: wordpress
       MYSQL_USER: user
       MYSQL_PASSWORD: password

   app:
     depends_on:
       - db
     image: wordpress:latest
     ports:
       - "8000:80"
     restart: always
     volumes:
       - ./wp-content/:/var/www/html/wp-content
     environment:
       WORDPRESS_DB_HOST: db:3306
       WORDPRESS_DB_USER: user
       WORDPRESS_DB_PASSWORD: password
volumes:
    db_data:

And when I start this up, and go to localhost:8000 I can see the changes immediately without restarting the container (when I edit files in the editor).

My docker-compose.yml looks like this:

version: '3.7'

services:

  wordpress:
    build:
      context: ..
      dockerfile: .docker/php-fpm/Dockerfile
      args:
        WP_VERSION: ${WP_VERSION}
    container_name: dev-project-wp
    working_dir: /var/www/html
    tty: true
    depends_on:
      - database
    volumes:
      - ../:/var/www/html
      - ./php-fpm/php.ini:/usr/local/etc/php/conf.d/local.ini
    environment:
      DB_PORT: ${DB_PORT}
      DB_HOST: ${DB_HOST}
      DB_NAME: ${DB_NAME}
      DB_USER: ${DB_USER}
      DB_PASSWORD: ${DB_PASSWORD}
      AUTH_KEY: ${AUTH_KEY}
      SECURE_AUTH_KEY: ${SECURE_AUTH_KEY}
      LOGGED_IN_KEY: ${LOGGED_IN_KEY}
      NONCE_KEY: ${NONCE_KEY}
      AUTH_SALT: ${AUTH_SALT}
      SECURE_AUTH_SALT: ${SECURE_AUTH_SALT}
      LOGGED_IN_SALT: ${LOGGED_IN_SALT}
      NONCE_SALT: ${NONCE_SALT}
      DB_PREFIX: ${DB_PREFIX}
      WP_VERSION: ${WP_VERSION}
    ports:
      - '9000'
    expose:
      - '80'

  nginx:
    build:
      context: ..
      dockerfile: .docker/nginx/Dockerfile
      args:
        DOCKER_IMAGE_NAME_PHP: 'docker_wordpress'
    container_name: dev-project-nginx
    working_dir: /var/www/html
    restart: always
    volumes:
      - ./nginx/nginx.conf:/etc/nginx/nginx.conf
      - ./nginx/certs/dev.project.com.crt:/etc/nginx/dev.project.com.crt
      - ./nginx/certs/dev.project.com.key:/etc/nginx/dev.project.com.key
      - ../:/var/www/html
      - ./nginx/logs:/var/log/nginx
    depends_on:
      - wordpress
    ports:
      - "${NGINX_HOST_HTTP_PORT}:80"
      - "${NGINX_HOST_HTTPS_PORT}:443"

  database:
    image: mariadb:10.3
    volumes:
      - projectdb:/var/lib/mysql
    restart: always
    container_name: ${DB_HOST}
    environment:
      MYSQL_RANDOM_ROOT_PASSWORD: 1
      MYSQL_DATABASE: ${DB_NAME}
      MYSQL_USER: ${DB_USER}
      MYSQL_PASSWORD: ${DB_PASSWORD}
    ports:
      - "${DB_HOST_PORT}:${DB_PORT}"

  phpmyadmin:
    image: phpmyadmin/phpmyadmin
    container_name: dev-project-phpmyadmin
    external_links:
      - database
    depends_on:
      - database
    environment:
      MYSQL_RANDOM_ROOT_PASSWORD: 1
      MYSQL_USERNAME: root
      PMA_HOST: ${DB_HOST}
    ports:
      - "${PHPMYADMIN_HOST_PORT}:80"

  mailhog:
    image: mailhog/mailhog
    container_name: dev-project-mailhog
    ports:
      - "${MAILHOG_HOST_PORT_SMTP}:1025"
      - "${MAILHOG_HOST_PORT_WEB}:8025"

volumes:
  projectdb:

I have an .env that looks like this:

# required so we can reach the nginx server from other containers via that hostname
APP_HOST=dev.project.com

# nginx
NGINX_HOST_HTTP_PORT=8180
NGINX_HOST_HTTPS_PORT=8443

# database
DB_HOST_PORT=33060
DB_PORT=3306
DB_HOST=dev-project-db
DB_NAME=docker-project
DB_USER=wp
DB_PASSWORD=wp

#phpmyadmin
PHPMYADMIN_HOST_PORT=8088

# wordpress - https://api.wordpress.org/secret-key/1.1/salt/
AUTH_KEY=':1k7<tW.#pE-O%*nZv7qM@me.#PLE;7).#g<4_.]04,2cM|]:*r8|:osljhB]s*.'
SECURE_AUTH_KEY='N~?~Z0(ijZS%|cHe#~F!O.31N#;VQSI~QBL%~oWZFGfU6R`%k#(eD)2Mcm}wLh0a'
LOGGED_IN_KEY='y7T8hoW|Ik4eBUGWUs6j~O*j)k{hrZ`E.ujW+Za{`WPn9Xk.&g]*F(HsV~q0fL8g'
NONCE_KEY='V0aau(w+|CAW_.+ilIkYaIh]8Bz}@,DdX@yBi+!dD5Zy:,YO+<CF+oYwP+~jYE,r'
AUTH_SALT='_zQ C^rzH%wBmmyjO,KH`J-EIZm$.MIzK[b(ar2+TgO=P&hHQ7d*lPsd8*+xu{4u'
SECURE_AUTH_SALT='EL~r.88e=TYM>W&LP]BI(u_f,PLQY|m%+2(2TF%,|S,Wc4uYV)hVBpZ .KA$cGhY'
LOGGED_IN_SALT='hEoqqkkJO~f`|p~43>gZx$;u&% {qJLe$OnreM,dfR`H?an+q3g`&9>?-v3iSoJ&'
NONCE_SALT='jfEVaR]Od2,yDPN|$o+g7Hd=XIwM,ow#a,,u|~d+pf/<T#NBcm(u9v?qpr#g^q5k'

DB_PREFIX=wp_
WP_VERSION=5.2.2

# mailhog
MAILHOG_HOST_PORT_SMTP=1028
MAILHOG_HOST_PORT_WEB=8028

My php dockerfile looks like this

ARG WP_VERSION

# Stage 0, build app
FROM php:7.3-fpm-stretch as build-container

RUN curl -sS https://getcomposer.org/installer | php \
  && chmod +x composer.phar && mv composer.phar /usr/local/bin/composer

RUN apt-get update && apt-get install -y gnupg
RUN curl -sL https://deb.nodesource.com/setup_11.x | bash - && \
    apt-get install -yq nodejs build-essential \
        git unzip \
        libfreetype6-dev \
        libjpeg62-turbo-dev \
        libpng-dev \
        pkg-config \
        libmcrypt-dev \
        libpng-dev \
    && pecl install mcrypt-1.0.2 \
    && docker-php-ext-enable mcrypt \
    && docker-php-ext-install bcmath \
    && docker-php-ext-install -j$(nproc) mysqli \
    && docker-php-ext-configure gd --with-freetype-dir=/usr/include/ --with-jpeg-dir=/usr/include/ \
    && docker-php-ext-install -j$(nproc) gd

RUN npm install -g npm

WORKDIR /

WORKDIR /build
COPY . /build

RUN cp /build/wp-config.php.template /build/wp-config.php
# RUN bash /build/scripts/build-plugins.sh

# Stage 2, build app container
FROM php:7.3-fpm-stretch
ARG WP_VERSION

RUN apt-get update && apt-get install -y \
        libfreetype6-dev \
        libjpeg62-turbo-dev \
        libmcrypt-dev \
        libpng-dev \
        libzip-dev \
        unzip \
        mariadb-client \
        libmagickwand-dev \
    && docker-php-ext-configure gd --with-png-dir=/usr/include/ --with-freetype-dir=/usr/include/ --with-jpeg-dir=/usr/include/ \
    && docker-php-ext-install -j$(nproc) \
        bcmath \
        exif \
        gd \
        mysqli \
        opcache \
        zip \
        pdo \
        pdo_mysql \
        mysqli \
    && docker-php-ext-install -j$(nproc) iconv \
    && export CFLAGS="$PHP_CFLAGS" CPPFLAGS="$PHP_CPPFLAGS" LDFLAGS="$PHP_LDFLAGS" \
    && rm -rf /var/lib/apt/lists/* \
    && pecl install imagick-3.4.4 \
    && docker-php-ext-enable imagick

ADD https://downloads.wordpress.org/release/wordpress-$WP_VERSION-no-content.zip /var/www/latest.zip
RUN cd /var/www && unzip latest.zip && rm latest.zip
RUN rm -rf /var/www/html
RUN mkdir -p /var/www/html \
    && mv /var/www/wordpress/* /var/www/html/

# Copy wp files
COPY --from=build-container /build/ /var/www/html/
RUN chown www-data:www-data /var/www/html/ -R
COPY .docker/php-fpm/php.ini /usr/local/etc/php/
WORKDIR /var/www/html/

CMD ["php-fpm"]

And the dockerfile for nginx looks like this

ARG DOCKER_IMAGE_NAME_PHP
FROM $DOCKER_IMAGE_NAME_PHP as php-image

FROM nginx:latest

COPY .docker/nginx/scripts/docker-nginx-entrypoint.sh /docker-nginx-entrypoint.sh
COPY .docker/nginx/nginx.conf /opt/nginx.conf

COPY --from=php-image /var/www/html/ /var/www/html/

CMD ["/bin/bash","/docker-nginx-entrypoint.sh"]

The nginx.conf looks like this:

worker_processes auto;

events {
  worker_connections  2048;
}


http {

  include       mime.types;

  index index.php index.html index.htm;

  server {
    listen 80;
    listen [::]:80;

    listen 443 ssl;
    listen [::]:443 ssl;

    server_name dev.project.com;

    ssl_certificate /etc/nginx/dev.project.com.crt;
    ssl_certificate_key /etc/nginx/dev.project.com.key;

    root /var/www/html;

    access_log /var/log/nginx/access.log;
    error_log /var/log/nginx/error.log;

    client_max_body_size 128M;

    location = /favicon.ico {
      log_not_found off;
      access_log off;
    }

    location / {
      try_files $uri $uri/ /index.php?$args;
    }

    location ~ \.php$ {
      include fastcgi_params;
      fastcgi_intercept_errors on;
      fastcgi_pass wordpress:9000;
      fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
      fastcgi_param QUERY_STRING    $query_string;
    }

    location ~* \.(js|css|png|jpg|jpeg|gif|ico)$ {
      expires max;
      log_not_found off;
    }
  }
}

And the docker-nginx-entrypoint.sh script looks like this

#!/bin/bash
set -e

cp /opt/nginx.conf /etc/nginx/conf.d/default.conf

exec nginx -g "daemon off;"

To start the docker I use

docker-compose -f .docker/docker-compose.yml --project-directory .docker up -d --build

I looked at the logs, and there is no error (in the wp container or nginx logs). The site works fine when I go to https://localhost:8443/wp-admin/ but the changes are propagated only on container reset. And it makes no sense (not to mention that it's basically an unusable dev environment).

PS

This is a bit more complicated setup, if you have any advice on simplifying it, the advice is welcomed.

EDIT

I'm bundling the assets using webpack, and when they are bundled, the changes are visible. The changes to the PHP file are not...

EDIT 2

I've used the official images for nginx and for wordpress, and the PHP part is again only changed on restart, so it's not the problem in the Dockerfiles.

Answer 1

So it turns out that the culprit was the opcache . Or rather me finding some example on line and just adding it to my php.ini without trying to understand what this actually means.

After reading this article and this excellent article that explains some opcache settings, I realised that my php.ini file had

opcache.revalidate_freq=60

Which you shouldn't have on your local development environment!

When used with opcache.validate_timestamps , PHP checks the revalidate_freq setting and uses it as a timestamp - if you made a request within 60 seconds (like the above example), the code will be pulled from the opcache - and you won't see any change in your browser. Only after 60 seconds will this change be visible.

So setting it to 0 (checking code on every single request) solves the issue.

Point of the story: check everything and read about every settings that you use!

'Unfortunately' for me I was reading the nginx config because I thought I messed something up there 😁