Hi,

I’m building a phoenix application and use Pow and Pow Assent for authentication. Pow assent requires sensitive information like provider ID and SECRET for social auth. GitHub - pow-auth/pow_assent: Multi-provider authentication for your Pow enabled app

These values are set via environment variables.

My GitHub action:

name: Fly Deploy

on:
  push:
    branches:
      - main

env:
  FLY_API_TOKEN: ${{ secrets.FLY_API_TOKEN }}
  FACEBOOK_AUTH_ID: ${{ secrets.FACEBOOK_AUTH_ID }}
  FACEBOOK_AUTH_SECRET: ${{ secrets.FACEBOOK_AUTH_SECRET }}
  GOOGLE_AUTH_ID: ${{ secrets.GOOGLE_AUTH_ID }}
  GOOGLE_AUTH_SECRET: ${{ secrets.GOOGLE_AUTH_SECRET }}

jobs:
  dependencies:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        elixir: ["1.13.4"]
        otp: ["24.3"]
    steps:
      - name: Cancel previous runs
        uses: styfle/cancel-workflow-action@0.9.1
        with:
          access_token: ${{ github.token }}
      - name: Checkout Github repo
        uses: actions/checkout@v3
      - name: Sets up an Erlang/OTP environment
        uses: erlef/setup-beam@v1
        with:
          elixir-version: ${{ matrix.elixir }}
          otp-version: ${{ matrix.otp }}
      - name: Retrieve cached dependencies
        uses: actions/cache@v3
        id: mix-cache
        with:
          path: |
            deps
            _build
          key: ${{ runner.os }}-${{ matrix.otp }}-${{ matrix.elixir }}-${{ hashFiles('mix.lock') }}
      - name: Install dependencies
        if: steps.mix-cache.outputs.cache-hit != 'true'
        run: |
          mix local.rebar --force
          mix local.hex --force
          mix deps.get
          mix deps.compile
  test:
    needs: dependencies
    runs-on: ubuntu-latest
    strategy:
      matrix:
        elixir: ["1.13.4"]
        otp: ["24.3"]
    services:
      db:
        image: postgres:latest
        ports: ["5432:5432"]
        env:
          POSTGRES_PASSWORD: postgres
        options: --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 5
    steps:
      - name: Cancel previous runs
        uses: styfle/cancel-workflow-action@0.9.1
        with:
          access_token: ${{ github.token }}
      - name: Checkout Github repo
        uses: actions/checkout@v3
      - name: Sets up an Erlang/OTP environment
        uses: erlef/setup-beam@v1
        with:
          elixir-version: ${{ matrix.elixir }}
          otp-version: ${{ matrix.otp }}
      - name: Retrieve cached dependencies
        uses: actions/cache@v3
        id: mix-cache
        with:
          path: |
            deps
            _build
          key: ${{ runner.os }}-${{ matrix.otp }}-${{ matrix.elixir }}-${{ hashFiles('mix.lock') }}
      - run: mix test

  deploy:
    needs: test
    name: Deploy app
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      - uses: superfly/flyctl-actions/setup-flyctl@master
      - run: flyctl deploy --remote-only

and Dockerfile

# Find eligible builder and runner images on Docker Hub. We use Ubuntu/Debian instead of
# Alpine to avoid DNS resolution issues in production.
#
# https://hub.docker.com/r/hexpm/elixir/tags?page=1&name=ubuntu
# https://hub.docker.com/_/ubuntu?tab=tags
#
#
# This file is based on these images:
#
#   - https://hub.docker.com/r/hexpm/elixir/tags - for the build image
#   - https://hub.docker.com/_/debian?tab=tags&page=1&name=bullseye-20210902-slim - for the release image
#   - https://pkgs.org/ - resource for finding needed packages
#   - Ex: hexpm/elixir:1.13.4-erlang-25.0-debian-bullseye-20210902-slim
#
ARG ELIXIR_VERSION=1.13.4
ARG OTP_VERSION=25.0
ARG DEBIAN_VERSION=bullseye-20210902-slim

ARG BUILDER_IMAGE="hexpm/elixir:${ELIXIR_VERSION}-erlang-${OTP_VERSION}-debian-${DEBIAN_VERSION}"
ARG RUNNER_IMAGE="debian:${DEBIAN_VERSION}"

FROM ${BUILDER_IMAGE} as builder

# install build dependencies
RUN apt-get update -y && apt-get install -y build-essential git \
    && apt-get clean && rm -f /var/lib/apt/lists/*_*

# prepare build dir
WORKDIR /app

# install hex + rebar
RUN mix local.hex --force && \
    mix local.rebar --force

# set build ENV
ENV MIX_ENV="prod"
ENV FACEBOOK_AUTH_ID=${FACEBOOK_AUTH_ID}
ENV FACEBOOK_AUTH_SECRET=${FACEBOOK_AUTH_SECRET}
ENV GOOGLE_AUTH_ID=${GOOGLE_AUTH_ID}
ENV GOOGLE_AUTH_SECRET=${GOOGLE_AUTH_SECRET}

# install mix dependencies
COPY mix.exs mix.lock ./
RUN mix deps.get --only $MIX_ENV
RUN mkdir config

# copy compile-time config files before we compile dependencies
# to ensure any relevant config change will trigger the dependencies
# to be re-compiled.
COPY config/config.exs config/${MIX_ENV}.exs config/
RUN mix deps.compile $FACEBOOK_AUTH_ID $FACEBOOK_AUTH_SECRETFACEBOOK_AUTH_SECRET $GOOGLE_AUTH_ID $GOOGLE_AUTH_SECRET

COPY priv priv

COPY lib lib

COPY assets assets

# compile assets
RUN mix assets.deploy

# Compile the release
RUN mix compile

# Changes to config/runtime.exs don't require recompiling the code
COPY config/runtime.exs config/

COPY rel rel
RUN mix release

# start a new build stage so that the final image will only contain
# the compiled release and other runtime necessities
FROM ${RUNNER_IMAGE}

RUN apt-get update -y && apt-get install -y libstdc++6 openssl libncurses5 locales \
  && apt-get clean && rm -f /var/lib/apt/lists/*_*

# Set the locale
RUN sed -i '/en_US.UTF-8/s/^# //g' /etc/locale.gen && locale-gen

ENV LANG en_US.UTF-8
ENV LANGUAGE en_US:en
ENV LC_ALL en_US.UTF-8

WORKDIR "/app"
RUN chown nobody /app

# set runner ENV
ENV MIX_ENV="prod"
ENV FACEBOOK_AUTH_ID=${FACEBOOK_AUTH_ID}
ENV FACEBOOK_AUTH_SECRET=${FACEBOOK_AUTH_SECRET}
ENV GOOGLE_AUTH_ID=${GOOGLE_AUTH_ID}
ENV GOOGLE_AUTH_SECRET=${GOOGLE_AUTH_SECRET}

# Only copy the final release from the build stage
COPY --from=builder --chown=nobody:root /app/_build/${MIX_ENV}/rel/handsomegig ./

USER nobody

CMD ["/app/bin/server"]
# Appended by flyctl
ENV ECTO_IPV6 true
ENV ERL_AFLAGS "-proto_dist inet6_tcp"

I have added these env variables in GitHub secrets

In prod my application is unable to access these secrets. Can anybody cross check