Dockerfile-overholt

FROM python:2.7
MAINTAINER hjhsalo <hjhsalo@gmail.com>

# NOTE: Baseimage python:2.7 already contains latest pip

# TODO: Compile cryptography (and everything else pip related) elsewhere and 
# get rid of "build-essential libssl-dev libffi-dev python-dev"
# Maybe according to these instructions: 
# https://glyph.twistedmatrix.com/2015/03/docker-deploy-double-dutch.html

# TODO: Double check and think about the order of commands. Should application 
# specific stuff be moved to the end of the file? 
# What are actually application specific? etc.

# TODO: Have brainstorming session on how to properly setup EXPOSE ports, hosts, etc.
# Now it is difficult to come up with sensible defaults.
# Remember to check out what Docker Compose offers.

# TODO: Make a new user and usergroup.
# Now everything including the ENTRYPOINT is being run as root which is bad
# practise and for example uWSGI complains about this.

###
# Install 
# Specific structure where a single RUN is used to execute everything.
# Based on Docker Best practices -document. To force cache busting.
# https://docs.docker.com/engine/userguide/eng-image/dockerfile_best-practices/#/apt-get
# NOTE: python-mysql.connector is MyData Account specific dependency.
RUN apt-get update && apt-get install -y \
    build-essential \
	libffi-dev \
    libssl-dev \
	python-dev \
	celeryd \
 && rm -rf /var/lib/apt/lists/*


### 
# Create a installation directory into the container
ARG APP_INSTALL_PATH=/mydata-sdk-components
ENV APP_INSTALL_PATH ${APP_INSTALL_PATH:-/mydata-sdk-components}

RUN mkdir -p $APP_INSTALL_PATH

# Change current directory inside the container / image to this path.
WORKDIR $APP_INSTALL_PATH

ARG OVERHOLT_APPLICATION_PATH=/
ENV OVERHOLT_APPLICATION_PATH ${OVERHOLT_APPLICATION_PATH:-/}


###
# Install application specific Python-dependencies.

# NOTE: If you have multiple Dockerfile steps that use different files from 
# your context, COPY them individually, rather than all at once. This will 
# ensure that each step’s build cache is only invalidated (forcing the step 
# to be re-run) if the specifically required files change.
# https://docs.docker.com/engine/userguide/eng-image/dockerfile_best-practices/#/add-or-copy
COPY $OVERHOLT_APPLICATION_PATH/requirements.txt /tmp/
RUN pip install --requirement /tmp/requirements.txt

# NOTE: j2cli is needed to preprocess config files based on values 
# environment variables
# https://github.com/kolypto/j2cli
# https://tryolabs.com/blog/2015/03/26/configurable-docker-containers-for-multiple-environments/
RUN pip install j2cli

# Copy everything (including previously copied filed and folders) from directory
# where Overholt -application is located to current WORKDIR inside container.
# Remember that <src> must be inside the context of the build:
# http://serverfault.com/a/666154
COPY .$OVERHOLT_APPLICATION_PATH .$OVERHOLT_APPLICATION_PATH


#### These will probably be removed when we start using uwsgi for all python applications
# Install a init-system in order to avoid python processes to return 137 (in response to SIGKILL)
#RUN apt-get update && apt-get install -y \
#    curl \
# && rm -rf /var/lib/apt/lists/*

ENV DUMB_INIT_VERSION v1.1.3
ENV DUMB_INIT_WOVERSION 1.1.3
RUN curl -SL https://github.com/Yelp/dumb-init/releases/download/${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_WOVERSION}_amd64.deb \
    -o dumb-init_${DUMB_INIT_WOVERSION}_amd64.deb \
    && dpkg -i dumb-init_*.deb

###
# Configure and run the application using entrypoint.sh.
# NOTE: Content of CMD are the default parameters passed to entrypoint.sh.
# These can be overwritten on "docker run <image> <parameters_that_replace_CMD>"
# https://docs.docker.com/engine/userguide/eng-image/dockerfile_best-practices/#/entrypoint
COPY ./docker-entrypoint-overholt.sh /

#ENTRYPOINT ["/docker-entrypoint-overholt.sh"]

#### These will probably be removed when we start using uwsgi for all python applications
ENTRYPOINT ["/usr/bin/dumb-init", "--"]

WORKDIR $APP_INSTALL_PATH$OVERHOLT_APPLICATION_PATH

# NOTE: Maybe this should be replaced with something that doesn't run anything 
# and the command below should go to compose.yml ??
#CMD ["sh", "-c", "python $APP_INSTALL_PATH${OVERHOLT_APPLICATION_PATH}/wsgi.py"]
CMD ["/docker-entrypoint-overholt.sh", "sh", "-c", "python $APP_INSTALL_PATH${OVERHOLT_APPLICATION_PATH}/wsgi.py"]