How to expose port from host to container in Docker? - docker

Question

You can use EXPOSE in Docker for:
The EXPOSE instructions informs Docker that the container will listen
on the specified network ports at runtime.
Can I do the opposite? Can I expose port from my Ubuntu to the docker container?
Background: I'm trying to setup a simple php7-fpm as a docker image and I would like to expose port 3306 (MySQL service) to the docker container.
My Dockerfile:
FROM debian:jessie
# persistent / runtime deps
RUN apt-get update && apt-get install -y ca-certificates curl libpcre3 librecode0 libsqlite3-0 libxml2 --no-install-recommends && rm -r /var/lib/apt/lists/*
# phpize deps
RUN apt-get update && apt-get install -y autoconf file g++ gcc libc-dev make pkg-config re2c --no-install-recommends && rm -r /var/lib/apt/lists/*
ENV PHP_INI_DIR /usr/local/etc/php
RUN mkdir -p $PHP_INI_DIR/conf.d
##<autogenerated>##
ENV PHP_EXTRA_CONFIGURE_ARGS --enable-fpm --with-fpm-user=www-data --with-fpm-group=www-data
##</autogenerated>##
ENV PHP_VERSION 7.0.0RC2
# --enable-mysqlnd is included below because it's harder to compile after the fact the extensions are (since it's a plugin for several extensions, not an extension in itself)
RUN buildDeps=" \
$PHP_EXTRA_BUILD_DEPS \
libcurl4-openssl-dev \
libpcre3-dev \
libreadline6-dev \
librecode-dev \
libsqlite3-dev \
libssl-dev \
libxml2-dev \
xz-utils \
" \
&& set -x \
&& apt-get update && apt-get install -y $buildDeps --no-install-recommends && rm -rf /var/lib/apt/lists/* \
&& curl -SL "https://downloads.php.net/~ab/php-$PHP_VERSION.tar.xz" -o php.tar.xz \
&& mkdir -p /usr/src/php \
&& tar -xof php.tar.xz -C /usr/src/php --strip-components=1 \
&& rm php.tar.xz* \
&& cd /usr/src/php \
&& ./configure \
--with-config-file-path="$PHP_INI_DIR" \
--with-config-file-scan-dir="$PHP_INI_DIR/conf.d" \
$PHP_EXTRA_CONFIGURE_ARGS \
--disable-cgi \
--enable-mysqlnd \
--with-pdo-mysql \
--enable-mbstring \
--with-curl \
--with-openssl \
--with-pcre \
--with-readline \
--with-recode \
--with-zlib \
&& make -j"$(nproc)" \
&& make install \
&& { find /usr/local/bin /usr/local/sbin -type f -executable -exec strip --strip-all '{}' + || true; } \
&& apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false -o APT::AutoRemove::SuggestsImportant=false $buildDeps \
&& make clean
COPY docker-php-ext-* /usr/local/bin/
##<autogenerated>##
WORKDIR /var/www/html
COPY php-fpm.conf /usr/local/etc/
EXPOSE 9000
CMD ["php-fpm"]
##</autogenerated>##
This is the command I use to run my container:
docker run --name=php7-fpm -v /var/www/html/:/var/www/html/ -p 9002:9000 marty/php7
My PHP app database configuration:
database:
main:
host: 127.0.0.1
dbname: edu
user: root
password: myPassword
port: 3306

Answer 1

You can run container with --net=host then it will have access to the host's ports directly. See https://docs.docker.com/engine/reference/run/#network-settings