add and configure database container

docker-compose.yml

@@ -1,8 +1,25 @@
 services:
 
+  db:
+    image: postgres:14-alpine
+    environment:
+      POSTGRES_DB: "gaehsnitzdb"
+      POSTGRES_USER: "gaehsnitzuser"
+      POSTGRES_PASSWORD: "SCKL97ukwICPpjJ9rXyhdljZ86T29A"
+    expose:
+      - "5432"
+
   web:
     build:
       context: .
+    environment:
+      DB_HOST: "db"
+      DB_PORT: "5432"
+      DB_NAME: "gaehsnitzdb"
+      DB_USER: "gaehsnitzuser"
+      DB_PASSWORD: "SCKL97ukwICPpjJ9rXyhdljZ86T29A"
+    depends_on:
+      - db
     ports:
       - "80:8000"
     volumes: