config interpolation, add user and db explicitly to make obvious that you can set these things

Author: raphaeltm

samples/django-channels-redis-postgres/README.md

@@ -29,10 +29,6 @@ The secret key for your Django application. You can generate a new one by runnin
 ### `POSTGRES_PASSWORD`
 The password for your Postgres database. You need to set this before deploying for the first time.
 
-### `POSTGRES_URL`
-The URL for your Postgres database (which should include the password set with `POSTGRES_PASSWORD`). This should be in the format `postgres://<username>:<password>@<host>:<port>/<database>`
-
-
 ## Deploying
 
 1. Open the terminal and type `defang login`

samples/django-channels-redis-postgres/compose.dev.yaml

@@ -8,7 +8,7 @@ services:
     healthcheck: {}
     environment:
       REDIS_URL: redis://redis-service:6379
-      POSTGRES_URL: postgres://user:password@postgres-service:5432/db
+      POSTGRES_URL: postgres://djangouser:djangopassword@postgres-service:5432/djangodatabase
       DEBUG: "True"
     depends_on:
       - redis-service
@@ -25,9 +25,9 @@ services:
       file: compose.yaml
       service: postgres-service
     environment:
-      POSTGRES_USER: user
-      POSTGRES_PASSWORD: password
-      POSTGRES_DB: db
+      POSTGRES_DB: djangodatabase
+      POSTGRES_USER: djangouser
+      POSTGRES_PASSWORD: djangopassword
     volumes:
       - postgres_data:/var/lib/postgresql/data
 

samples/django-channels-redis-postgres/compose.yaml

@@ -11,7 +11,7 @@ services:
         mode: ingress
     environment:
       REDIS_URL: redis://redis-service:6379
-      POSTGRES_URL: "postgres://postgres:${POSTGRES_PASSWORD}@postgres-service:5432/postgres?sslmode=require"
+      POSTGRES_URL: "postgres://djangouser:${POSTGRES_PASSWORD}@postgres-service:5432/djangodatabase?sslmode=require"
       SECRET_KEY:
     healthcheck:
       # wget or curl required for healthchecks on services with a published port
@@ -33,3 +33,5 @@ services:
         target: 5432
     environment:
       POSTGRES_PASSWORD:
+      POSTGRES_DB: djangodatabase
+      POSTGRES_USER: djangouser