Dockerfile for django applications

Dockerfile

# syntax=docker/dockerfile:1.0.0-experimental

# The above comment is not to be deleted, its necessary. We are using an experimental feature and above line is important to enable that
# please refer to this, https://medium.com/@tonistiigi/build-secrets-and-ssh-forwarding-in-docker-18-09-ae8161d066 to know more about this
# before building docker image using this dockerfile, please do export DOCKER_BUILDKIT=1

FROM python:3.6-alpine

ENV PYTHONUNBUFFERED 1

WORKDIR /api/

COPY ./requirements/requirements.txt ./requirements.txt

# the secrets are used if you are installing any private package in requirements
# installing essential packages for building and running packages
# the packages needed for build are later removed while the packages
# needed for running are kept
RUN --mount=type=secret,id=git_token,dst=/git_token export GIT_ACCESS_TOKEN=$(cat /git_token) \
    && apk add --no-cache --virtual .build-deps \
    ca-certificates gcc postgresql-dev linux-headers musl-dev \
    libffi-dev jpeg-dev zlib-dev git \
    && pip install -r ./requirements.txt \
    && find /usr/local \
        \( -type d -a -name test -o -name tests \) \
        -o \( -type f -a -name '*.pyc' -o -name '*.pyo' \) \
        -exec rm -rf '{}' + \
    && runDeps="$( \
        scanelf --needed --nobanner --recursive /usr/local \
                | awk '{ gsub(/,/, "\nso:", $2); print "so:" $2 }' \
                | sort -u \
                | xargs -r apk info --installed \
                | sort -u \
    )" \
    && apk add --virtual .rundeps $runDeps \
    && apk del .build-deps \
    && rm -rf src/my-package-name/.git/ # this command is only useful if you are installing a private package

# copying the code
COPY ./ ./

## this command will run on container creation
ENTRYPOINT ["/bin/sh", "start.sh"]