♻️ Simplify environment configuration (#2413)

Author: tiangolo

.env

@@ -6,18 +6,17 @@ DOMAIN=localhost
 # DOMAIN=localhost.tiangolo.com
 
 # Public frontend URL, used by the backend to generate links in emails.
-# Keep the Vite URL for local development; deployments use the application URL.
+# Deployments derive this from DOMAIN in compose.deploy.yml.
 FRONTEND_HOST=http://localhost:5173
-# In staging and production, set this env var to the frontend host, e.g.
-# FRONTEND_HOST=https://example.com
 
 # Environment: local, staging, production
 ENVIRONMENT=local
 
 PROJECT_NAME="Full Stack FastAPI Project"
 
 # Backend
-BACKEND_CORS_ORIGINS="http://localhost,https://localhost,http://localhost.tiangolo.com"
+# Additional allowed CORS origins, separated by commas
+BACKEND_CORS_ORIGINS=
 SECRET_KEY=changethis
 FIRST_SUPERUSER=admin@example.com
 FIRST_SUPERUSER_PASSWORD=changethis
@@ -39,6 +38,3 @@ POSTGRES_USER=postgres
 POSTGRES_PASSWORD=changethis
 
 SENTRY_DSN=
-
-# Configure these with your own Docker registry images
-DOCKER_IMAGE_BACKEND=backend

.github/workflows/deploy-production.yml

@@ -19,7 +19,6 @@ jobs:
     env:
       ENVIRONMENT: production
       DOMAIN: ${{ secrets.DOMAIN }}
-      FRONTEND_HOST: https://${{ secrets.DOMAIN }}
       SECRET_KEY: ${{ secrets.SECRET_KEY }}
       FIRST_SUPERUSER: ${{ secrets.FIRST_SUPERUSER }}
       FIRST_SUPERUSER_PASSWORD: ${{ secrets.FIRST_SUPERUSER_PASSWORD }}

.github/workflows/deploy-staging.yml

@@ -19,7 +19,6 @@ jobs:
     env:
       ENVIRONMENT: staging
       DOMAIN: ${{ secrets.DOMAIN }}
-      FRONTEND_HOST: https://${{ secrets.DOMAIN }}
       SECRET_KEY: ${{ secrets.SECRET_KEY }}
       FIRST_SUPERUSER: ${{ secrets.FIRST_SUPERUSER }}
       FIRST_SUPERUSER_PASSWORD: ${{ secrets.FIRST_SUPERUSER_PASSWORD }}

compose.deploy.yml

@@ -44,8 +44,14 @@ services:
       # Use the Let's Encrypt resolver
       - traefik.http.routers.adminer-https.tls.certresolver=le
 
+  prestart:
+    environment:
+      FRONTEND_HOST: https://${DOMAIN?Variable not set}
+
   backend:
     restart: always
+    environment:
+      FRONTEND_HOST: https://${DOMAIN?Variable not set}
     labels:
       # Route HTTPS traffic for this domain
       - traefik.http.routers.backend-https.rule=Host(`${DOMAIN?Variable not set}`)

compose.yml

@@ -49,65 +49,36 @@ services:
       # Define the port inside of the Docker service to use
       - traefik.http.services.adminer.loadbalancer.server.port=8080
 
-  prestart:
-    image: '${DOCKER_IMAGE_BACKEND?Variable not set}:${TAG-latest}'
-    build:
-      context: .
-      dockerfile: backend/Dockerfile
-    depends_on:
-      db:
-        condition: service_healthy
-        restart: true
-    command: bash scripts/prestart.sh
-    env_file:
-      - .env
-    environment:
-      - DOMAIN=${DOMAIN}
-      - FRONTEND_HOST=${FRONTEND_HOST?Variable not set}
-      - ENVIRONMENT=${ENVIRONMENT}
-      - BACKEND_CORS_ORIGINS=${BACKEND_CORS_ORIGINS}
-      - SECRET_KEY=${SECRET_KEY?Variable not set}
-      - FIRST_SUPERUSER=${FIRST_SUPERUSER?Variable not set}
-      - FIRST_SUPERUSER_PASSWORD=${FIRST_SUPERUSER_PASSWORD?Variable not set}
-      - SMTP_HOST=${SMTP_HOST}
-      - SMTP_USER=${SMTP_USER}
-      - SMTP_PASSWORD=${SMTP_PASSWORD}
-      - EMAILS_FROM_EMAIL=${EMAILS_FROM_EMAIL}
-      - POSTGRES_SERVER=db
-      - POSTGRES_PORT=${POSTGRES_PORT}
-      - POSTGRES_DB=${POSTGRES_DB}
-      - POSTGRES_USER=${POSTGRES_USER?Variable not set}
-      - POSTGRES_PASSWORD=${POSTGRES_PASSWORD?Variable not set}
-      - SENTRY_DSN=${SENTRY_DSN}
-
   backend:
-    image: '${DOCKER_IMAGE_BACKEND?Variable not set}:${TAG-latest}'
+    image: backend:latest
     depends_on:
       db:
         condition: service_healthy
         restart: true
       prestart:
         condition: service_completed_successfully
-    env_file:
-      - .env
-    environment:
-      - DOMAIN=${DOMAIN}
-      - FRONTEND_HOST=${FRONTEND_HOST?Variable not set}
-      - ENVIRONMENT=${ENVIRONMENT}
-      - BACKEND_CORS_ORIGINS=${BACKEND_CORS_ORIGINS}
-      - SECRET_KEY=${SECRET_KEY?Variable not set}
-      - FIRST_SUPERUSER=${FIRST_SUPERUSER?Variable not set}
-      - FIRST_SUPERUSER_PASSWORD=${FIRST_SUPERUSER_PASSWORD?Variable not set}
-      - SMTP_HOST=${SMTP_HOST}
-      - SMTP_USER=${SMTP_USER}
-      - SMTP_PASSWORD=${SMTP_PASSWORD}
-      - EMAILS_FROM_EMAIL=${EMAILS_FROM_EMAIL}
-      - POSTGRES_SERVER=db
-      - POSTGRES_PORT=${POSTGRES_PORT}
-      - POSTGRES_DB=${POSTGRES_DB}
-      - POSTGRES_USER=${POSTGRES_USER?Variable not set}
-      - POSTGRES_PASSWORD=${POSTGRES_PASSWORD?Variable not set}
-      - SENTRY_DSN=${SENTRY_DSN}
+    # The YAML anchor lets the prestart service reuse this environment mapping.
+    environment: &backend-environment
+      FRONTEND_HOST: ${FRONTEND_HOST?Variable not set}
+      ENVIRONMENT: ${ENVIRONMENT}
+      PROJECT_NAME: ${PROJECT_NAME?Variable not set}
+      BACKEND_CORS_ORIGINS: ${BACKEND_CORS_ORIGINS}
+      SECRET_KEY: ${SECRET_KEY?Variable not set}
+      FIRST_SUPERUSER: ${FIRST_SUPERUSER?Variable not set}
+      FIRST_SUPERUSER_PASSWORD: ${FIRST_SUPERUSER_PASSWORD?Variable not set}
+      SMTP_HOST: ${SMTP_HOST}
+      SMTP_USER: ${SMTP_USER}
+      SMTP_PASSWORD: ${SMTP_PASSWORD}
+      EMAILS_FROM_EMAIL: ${EMAILS_FROM_EMAIL}
+      SMTP_TLS: ${SMTP_TLS}
+      SMTP_SSL: ${SMTP_SSL}
+      SMTP_PORT: ${SMTP_PORT}
+      POSTGRES_SERVER: db
+      POSTGRES_PORT: ${POSTGRES_PORT}
+      POSTGRES_DB: ${POSTGRES_DB}
+      POSTGRES_USER: ${POSTGRES_USER?Variable not set}
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD?Variable not set}
+      SENTRY_DSN: ${SENTRY_DSN}
 
     healthcheck:
       test: ["CMD", "curl", "-f", "http://localhost:8000/api/v1/utils/health-check/"]
@@ -129,5 +100,17 @@ services:
       - traefik.http.routers.backend-http.rule=Host(`${DOMAIN?Variable not set}`)
       - traefik.http.routers.backend-http.entrypoints=http
 
+  prestart:
+    image: backend:latest
+    build:
+      context: .
+      dockerfile: backend/Dockerfile
+    depends_on:
+      db:
+        condition: service_healthy
+        restart: true
+    command: bash scripts/prestart.sh
+    environment: *backend-environment
+
 volumes:
   app-db-data:

deployment.md

@@ -58,6 +58,8 @@ Set the `DOMAIN`, by default `localhost` (for development), but when deploying y
 export DOMAIN=fastapi-project.example.com
 ```
 
+The deployment Docker Compose configuration also uses `DOMAIN` to set the public frontend URL used in links generated by the backend.
+
 Set the `POSTGRES_PASSWORD` to something different than `changethis`:
 
 ```bash
@@ -72,18 +74,12 @@ export SECRET_KEY="changethis"
 
 Note: you can use the Python command above to generate a secure secret key.
 
-Set the `FIRST_SUPER_USER_PASSWORD` to something different than `changethis`:
+Set the `FIRST_SUPERUSER_PASSWORD` to something different than `changethis`:
 
 ```bash
 export FIRST_SUPERUSER_PASSWORD="changethis"
 ```
 
-Set the `FRONTEND_HOST` to the application URL. It is used to generate links in emails:
-
-```bash
-export FRONTEND_HOST="https://${DOMAIN?Variable not set}"
-```
-
 You can set several other environment variables:
 
 * `PROJECT_NAME`: The name of the project, used in the API for the docs and emails.