install postgres

Dockerfile

@@ -12,11 +12,15 @@ EXPOSE 8000
 ARG DEV=false
 RUN python -m venv /py && \
     /py/bin/pip install --upgrade pip && \
+    apk add --update --no-cache postgresql-client && \
+    apk add --update --no-cache --virtual .tmp-build-deps \
+        build-base postgresql-dev musl-dev && \
     /py/bin/pip install -r /tmp/requirements.txt && \
     if [ $DEV = "true" ]; \
         then /py/bin/pip install -r /tmp/requirements.dev.txt ; \
     fi && \
     rm -rf /tmp && \
+    apk del .tmp-build-deps && \
     adduser \
         --disabled-password \
         --no-create-home \

app/app/calc.py

@@ -4,4 +4,4 @@ def add(x,y):
     return x + y
 
 def subtract(x,y):
-    return x - y
+    return x - y

app/app/tests.py

@@ -12,4 +12,5 @@ def test_add_numbers(self):
 
     def test_subtract_numbers(self):
         res = calc.subtract(10, 5)
-        self.assertEqual(res, 5)
+        self.assertEqual(res, 5)
+

docker-compose.yml

@@ -12,3 +12,24 @@ services:
       - ./app:/app
     command: >
       sh -c "python manage.py runserver 0.0.0.0:8000"
+    environment:
+      - DB_HOST=db
+      - DB_NAME=devdb
+      - DB_USER=devuser
+      - DB_PASSWORD=changeme
+    depends_on:
+      - db
+
+  db:
+    image: postgres:13-alpine
+    volumes:
+      - dev-db-data:/var/lib/postgresql/data
+    environment:
+      - POSTGRES_DB=devdb
+      - POSTGRES_USER=devuser
+      - POSTGRES_PASSWORD=changeme
+
+
+volumes:
+  dev-db-data:
+

requirements.txt

@@ -1,2 +1,3 @@
 Django>=3.2.4,<3.3
 djangorestframework>=3.12.4,<3.13
+psycopg2>=2.8.6,<2.9