I’ve some problems deploying my existing application to aws’s elastic beanstalk.
I’m struggling with the environment variables because I’m receiving the following error from the logs:

-------------------------------------
/var/log/eb-docker/containers/eb-current-app/unexpected-quit.log
-------------------------------------
    (db_connection) lib/db_connection/connection.ex:69: DBConnection.Connection.connect/2
    (connection) lib/connection.ex:622: Connection.enter_connect/5
    (stdlib) proc_lib.erl:249: :proc_lib.init_p_do_apply/3
Last message: nil
11:05:31.352 [error] GenServer #PID<0.477.0> terminating
** (RuntimeError) connect raised KeyError exception: key :database not found. The exception details are hidden, as they may contain sensitive data such as database credentials. You may set :show_sensitive_data_on_connection_error to true when starting your connection if you wish to see all of the details
    (elixir) lib/keyword.ex:393: Keyword.fetch!/2
    (postgrex) lib/postgrex/protocol.ex:92: Postgrex.Protocol.connect/1
    (db_connection) lib/db_connection/connection.ex:69: DBConnection.Connection.connect/2
    (connection) lib/connection.ex:622: Connection.enter_connect/5
    (stdlib) proc_lib.erl:249: :proc_lib.init_p_do_apply/3
Last message: nil

My prod.exs looks like this:

use Mix.Config

config :supercoolapplication, SuperCoolApplicationWeb.Endpoint,
  http: [port: {:system, "PORT"}, compress: true],
  url: [scheme: "http", host: System.get_env("HOST"), port: {:system, "PORT"}],
  secret_key_base: System.get_env("SECRET_KEY_BASE"),
  code_reloader: false,
  cache_static_manifest: "priv/static/cache_manifest.json",
  server: true

# Do not print debug messages in production
config :logger, level: :info

config :phoenix_crud, PhoenixCrud.Repo,
  adapter: Ecto.Adapters.Postgres,
  database: System.get_env("RDS_DB_NAME"),
  username: System.get_env("RDS_USERNAME"),
  password: System.get_env("RDS_PASSWORD"),
  hostname: System.get_env("RDS_HOSTNAME"),
  port: System.get_env("RDS_PORT") || 5432,
  pool_size: 20,
  ssl: true

I basically followed this tutorial on thoughtbot.

My Dockerfile looks like this:

FROM bitwalker/alpine-elixir-phoenix:latest

# Set exposed ports
EXPOSE 4000
ENV PORT=4000 MIX_ENV=dev

# Cache elixir deps
ADD mix.exs mix.lock ./
RUN mix do deps.get, deps.compile

# Same with npm deps
ADD assets/package.json assets/
RUN cd assets && \
    npm install

ADD . .

# Run frontend build, compile, and digest assets
RUN cd assets/ && \
    npm run deploy && \
    cd - && \
    mix do compile, phx.digest

USER default

CMD ["mix", "phx.server"]

I created my elastic beanstalk environment like the following:

eb create \
  --database \
  -db.engine postgres \
  -db.i db.t2.small \
  -db.size 10 \
  -db.version 9.4.5 \
  --envvars MIX_ENV=prod,SECRET_KEY_BASE=heregoesmyprettysecurekey,PORT=4000

Has anyone an idea what is going wrong on my side?
And I’m also questioning myself on how I should actually run the mix ecto.create task and then after every deployment the mix ecto.migrate task…

I would be happy about any help!!!