CODEWITHSUNDEEP
shelldockerstartup
DS87
DS87

Reputation: 602

Excecute .sh file on start of Docker container and let container run

I have a docker container that serves a webserver. On every startup of the container, I want to excecute a little shell script. The script that has to be executed has only one statement. 

/var/www/html/app/Console/cake schema update -y

To achieve this, I created a .sh file called schemaupdate.sh which I copy into the docker container using the dockerfile into the /etc/init.d folder. Furthermore I make it executable and register it to the startup.

COPY schemaupdate.sh /etc/init.d/schemaupdate.sh
chmod 755 /etc/init.d/schemaupdate.sh
update-rc.d schemaupdate.sh defaults

The file is successfully copied into the container. However, the script is not executed when the docker container starts. When I manually call the sh file, everything is running fine.

How can I achieve, that the file / statement is executed on each startup of a container? It is important, that the script is executed at the startup and the container (so the webserver) still continues to run! The script only makes a little update check and after the check the webserver keeps on going.

The container is a debian based container. Here is inital dockerfile.

#start with base Image from php 
FROM php:7.3-apache

#install system dependencies and enable PHP modules

RUN apt-get update && apt-get install -y \
      libicu-dev \
      libpq-dev \
      libmcrypt-dev \
      mysql-client \
      git \
      zip \
      unzip \
    && rm -r /var/lib/apt/lists/* \
    && docker-php-ext-configure pdo_mysql --with-pdo-mysql=mysqlnd \
    && docker-php-ext-install \
      intl \
      mbstring \
      pcntl \
      pdo_mysql \
      pdo_pgsql \
      pgsql \
      opcache

#     zip \
#     mcrypt \

#configure imap for mails
RUN apt-get update && \
    apt-get install -y \
        libc-client-dev libkrb5-dev && \
    rm -r /var/lib/apt/lists/*

RUN docker-php-ext-configure imap --with-kerberos --with-imap-ssl && \
docker-php-ext-install -j$(nproc) imap


#install mcrypt
RUN apt-get update \
    && apt-get install -y libmcrypt-dev \
    && rm -rf /var/lib/apt/lists/* \
    && pecl install mcrypt-1.0.2 \
    && docker-php-ext-enable mcrypt

#install composer
RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/bin/ --filename=composer

#set our application folder as an environment variable
ENV APP_HOME /var/www/html

#change uid and gid of apache to docker user uid/gid
RUN usermod -u 1000 www-data && groupmod -g 1000 www-data

#change the web_root to cakephp /var/www/html/webroot folder
#RUN sed -i -e "s/html/html\/webroot/g" /etc/apache2/sites-enabled/000-default.conf

# enable apache module rewrite
RUN a2enmod rewrite

#copy source files and run composer
#COPY src/ /var/www/html
#COPY src/ $APP_HOME

# install all PHP dependencies
#RUN composer install --no-interaction

#SET Volume
VOLUME /var/www/html/

#change ownership of our applications
RUN chown -R www-data:www-data $APP_HOME

#SET ENV VARIABLES

COPY schemaupdate.sh /etc/init.d/schemaupdate.sh
chmod 755 /etc/init.d/schemaupdate.sh
update-rc.d schemaupdate.sh defaults

EXPOSE 80

Upvotes: 1

Views: 1673

Answers (2)

DS87
DS87

Reputation: 602

I Finally used the Entrypoint. I deleted the COPY, chmod and update-rc. The Entrypoint looks like the following.

ENTRYPOINT [ "sh", "-c", "/var/www/html/app/Console/cake schema update -y && /var/www/html/app/Console/cake schema update -y && /usr/sbin/apachectl -D FOREGROUND"]

It first starts the update statment. After this is finished (so terminated), the apachectl is called to keep the webserver running.

Upvotes: 1

John Kugelman
John Kugelman

Reputation: 361556

/etc/init.d/ isn't relevant. Containers aren't full blown operating systems with a heavyweight SysV init-style startup sequence. They run a single command, that's it.

You should either add the command as a RUN statement in the Dockerfile so its results are baked into the image, or you should have it called directly by the container's CMD or ENTRYPOINT directive.

Upvotes: 1

Related Questions