Docker Connects to 'Existing' database, But it Shows Empty – Debian

I’ve found about 15 different way to set up Docker to connect to an existing Postgre database. None of them work for me. It seems that I’m connecting to a database. It appears to be empty. This is the final output from docker-compose up –build:

db_1   |
db_1   | PostgreSQL Database directory appears to contain a database; Skipping initialization
db_1   |
db_1   | 2020-05-22 21:32:42.213 UTC [1] LOG:  starting PostgreSQL 12.2 (Debian 12.2-2.pgdg100+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 8.3.0-6) 8.3.0, 64-bit
db_1   | 2020-05-22 21:32:42.214 UTC [1] LOG:  listening on IPv4 address "0.0.0.0", port 5432
db_1   | 2020-05-22 21:32:42.214 UTC [1] LOG:  listening on IPv6 address "::", port 5432
db_1   | 2020-05-22 21:32:42.216 UTC [1] LOG:  listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
db_1   | 2020-05-22 21:32:42.227 UTC [26] LOG:  database system was shut down at 2020-05-22 21:32:32 UTC
db_1   | 2020-05-22 21:32:42.231 UTC [1] LOG:  database system is ready to accept connections
web_1  | Watching for file changes with StatReloader
web_1  | Performing system checks...
web_1  |
web_1  | System check identified no issues (0 silenced).
web_1  |
web_1  | You have 38 unapplied migration(s). Your project may not work properly until you apply the migrations for app(s): admin, auth, base, contenttypes, sessions.
web_1  | Run 'python manage.py migrate' to apply them.
web_1  | May 22, 2020 - 21:32:44
web_1  | Django version 3.0.4, using settings 'merrittsecurity.settings'
web_1  | Starting development server at http://0.0.0.0:8000/
web_1  | Quit the server with CONTROL-C.

The fact that it says I have 38 unapplied migrations tells me it’s working with an empty database. My PyCharm Django project works fine outside of Docker and it worked fine in Docker with SQLite3 before I converted it.

The log entry: listening on IPv4 address “0.0.0.0”, port 5432 seems odd. Could this be the problem?

docker-compose.yml:

version: '3.7'

services:
  db:
#    image: keinos/sqlite3:latest
    image: postgres
    expose:
      - 5432
    environment:
        - POSTGRES_DB=databsename
        - POSTGRES_USER=me
        - POSTGRES_PASSWORD=dbpassword
    volumes:
      - pgdata:/usr/local/var/postgresql/
  web:
    build: .
    command: python manage.py runserver 0.0.0.0:8000
    volumes:
      - .:/code
    ports:
      - "8005:8000"
    depends_on:
      - db
volumes:
  pgdata: {}

I’ve replaced the database name, user, and password here. They normally contain the actual values, not variables. I got this particular construction from several examples on how to set it up.

Dockerfile:

FROM ubuntu:18.04
FROM python:3.7.0-alpine

# Set work directory
RUN mkdir /code
WORKDIR /code

# Set environment variables
ENV PYTHONDONTWRITEBYTECODE 1
ENV PYTHONUNBUFFERED 1
ENV PYTHONMALLOC debug

# Install dependencies
# The next two lines were added to get postgre to build
RUN 
 apk add --no-cache postgresql-libs && 
 apk add --no-cache --virtual .build-deps gcc musl-dev postgresql-dev

# The next line was added to get pillow to build
RUN apk add build-base python-dev py-pip jpeg-dev zlib-dev

 #python3 -m pip install -r requirements.txt --no-cache-dir && 
 #apk --purge del .build-deps


#RUN apk add build-base python-dev py-pip jpeg-dev zlib-dev
ENV LIBRARY_PATH=/lib:/usr/lib

COPY requirements.txt /code/
RUN pip install --upgrade pip
RUN pip install -r requirements.txt
RUN apk --purge del .build-deps

# Copy django project
ADD . /code/

The pertinent section of setting.py:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'NAME': 'mydatabase',
        'USER': os.getenv('POSTGRE_USER'),
        'PASSWORD': os.getenv('POSTGRE_PASSWORD'),
        'HOST': os.getenv('POSTGRE_HOST'),
        'PORT': '5432',
    }
}

The POSTGRE_… values are in my .env file. They work fine outside of Docker with the exception of POSTGRE_HOST. I normally set it to localhost. That causes an error so I replaced it with db as per an example from the web. The other values are the same as supplied in the docker-compose.yml file above. This is on the latest version of MacOS. Any idea what I’m doing wrong?

In response to questions

psql shows a number of databases that I’ve added.

The database has about about six tables beyond the ones created in the initial Django migrate. If I run my project outside of Docker, I have no trouble accessing the database.

When I run SHOW data_directory; in pqsl it responds: /usr/local/var/postgres
I installed postgre on MacOS using homebrew.

The postgre sever is running on MacOS, the same one where I execute the docker-compose.

As mentioned the POSTGRE_… are ones I created to link to the actual data in .env. The .env file contains the actual values. These same values are repeated in the docker-compose.yml. I’m not it’s necessary to have them twice.