Clean up env variable management

.env.example

-DATABASE_URL="postgresql://postgres:postgres@postgres:5432/postgres"
-BODY_SIZE_LIMIT=10485760 # 10MiB - increase default body size limit in order to upload large files (product images)
+DB_USERNAME="postgres"
+DB_PASSWORD="postgres"
+DB_NAME="postgres"
+BODY_SIZE_LIMIT=10485760 # 10MiB

docker-compose.yml.example

@@ -4,15 +4,15 @@ services:
     image: postgres:11.1
     restart: always
     environment:
-      POSTGRES_PASSWORD: postgres
-      POSTGRES_USER: postgres
-      POSTGRES_DB: postgres
+      POSTGRES_PASSWORD: ${DB_PASSWORD}
+      POSTGRES_USER: ${DB_USERNAME}
+      POSTGRES_DB: ${DB_NAME}
     ports:
       - "5432:5432"
     volumes:
       - ./postgres-data:/var/lib/postgresql/data
     healthcheck:
-      test: ["CMD-SHELL", "pg_isready -U postgres -d postgres"]
+      test: ["CMD-SHELL", "pg_isready -U ${DB_USERNAME} -d ${DB_NAME}"]
       interval: 5s
       timeout: 30s
       retries: 5
@@ -26,8 +26,9 @@ services:
     depends_on:
       postgres:
         condition: service_healthy
-    env_file:
-      - .env
+    environment:
+      BODY_SIZE_LIMIT: ${BODY_SIZE_LIMIT}
+      DATABASE_URL: postgresql://${DB_USERNAME}:${DB_PASSWORD}@postgres:5432/${DB_NAME}
     volumes:
       - ./article-images:/app/article-images