working database connection in Django

compose.yaml

@@ -1,9 +1,46 @@
 services:
   web:
     build: .
+    depends_on:
+      - db
     ports:
       - 8000:8000
     environment:
-      - PYTHONDONTWRITEBYTECODE=1
-      - PYTHONUNBUFFERED=1
+      PYTHONDONTWRITEBYTECODE: 1
+      PYTHONUNBUFFERED: 1
+      DJANGO_SETTINGS_MODULE: ${DJANGO_SETTINGS_MODULE}
+      POSTGRES_DB: ${DB_NAME}
+      POSTGRES_USER: ${DB_USER}
+      POSTGRES_PASSWORD: ${DB_PASSWORD}
+      POSTGRES_HOST: ${DB_HOST}
+      POSTGRES_PORT: ${DB_PORT}
     restart: unless-stopped
+
+  db:
+    image: postgres:18
+    environment:
+      POSTGRES_DB: ${DB_NAME}
+      POSTGRES_USER: ${DB_USER}
+      POSTGRES_PASSWORD: ${DB_PASSWORD}
+    volumes:
+      - postgres_data:/var/lib/postgresql
+    restart: unless-stopped
+
+  adminer:
+    image: adminer
+    depends_on:
+      - db
+    restart: always
+    ports:
+      - 8080:8080
+
+  test:
+    build: .
+    command: python manage.py test
+    depends_on:
+      - db
+    profiles:
+      - test
+
+volumes:
+  postgres_data: