the-biergarten-app/docs/website/environment-variables.md

Environment variables

This document covers the active environment variables used by the current Biergarten stack.

Overview

The application uses environment variables for:

• .NET API backend - database connections, token secrets, runtime settings
• React Router website - API base URL and session signing
• Docker containers - environment-specific orchestration

Configuration patterns

Backend (.NET API)

Direct environment variable access via Environment.GetEnvironmentVariable().

Frontend (web/frontend)

The active website reads runtime values from the server environment for its auth and API integration.

Docker

Environment-specific .env files loaded via env_file: in docker-compose.yaml:

• .env.dev - Development
• .env.test - Testing
• .env.prod - Production

Backend variables (.NET API)

Database connection

Option 1: Component-Based (Recommended for Docker)

Build connection string from individual components:

DB_SERVER=sqlserver,1433          # SQL Server host and port
DB_NAME=Biergarten                # Database name
DB_USER=sa                        # SQL Server username
DB_PASSWORD=YourStrong!Passw0rd   # SQL Server password
DB_TRUST_SERVER_CERTIFICATE=True  # Optional, defaults to True

Option 2: Full Connection String (Local Development)

Provide complete connection string:

DB_CONNECTION_STRING="Server=localhost,1433;Database=Biergarten;User Id=sa;Password=YourStrong!Passw0rd;TrustServerCertificate=True;"

Priority: DB_CONNECTION_STRING is checked first. If not found, connection string is built from components.

Implementation: See DefaultSqlConnectionFactory.cs

JSON Web Token (JWT) authentication secrets (backend)

The backend uses separate secrets for different token types to enable independent key rotation and validation isolation.

# Access token secret (1-hour tokens)
ACCESS_TOKEN_SECRET=<generated-secret>              # Signs short-lived access tokens

# Refresh token secret (21-day tokens)
REFRESH_TOKEN_SECRET=<generated-secret>             # Signs long-lived refresh tokens

# Confirmation token secret (30-minute tokens)
CONFIRMATION_TOKEN_SECRET=<generated-secret>        # Signs email confirmation tokens

# Website base URL (used in confirmation emails)
WEBSITE_BASE_URL=https://thebiergarten.app          # Base URL for the website

Security Requirements:

• Use at least 32 characters per secret
• Use 127 or more characters in production
• Generate secrets with a cryptographically secure random function
• Never reuse secrets across token types or environments
• Rotate secrets periodically in production

Generate Secrets:

macOS/Linux - Generate a cryptographically secure base64 secret (127 raw bytes)

openssl rand -base64 127

Windows - PowerShell 5.1 compatible (cryptographically secure, 127 raw bytes)

$bytes = New-Object byte[] 127
$rng = [System.Security.Cryptography.RNGCryptoServiceProvider]::new()
$rng.GetBytes($bytes)
[Convert]::ToBase64String($bytes)
$rng.Dispose()

Windows - PowerShell 7+ compatible (cryptographically secure, 127 raw bytes)

[Convert]::ToBase64String([System.Security.Cryptography.RandomNumberGenerator]::GetBytes(127))

Token Expiration:

• Access tokens: 1 hour
• Refresh tokens: 21 days
• Confirmation tokens: 30 minutes

(Defined in TokenServiceExpirationHours class)

JWT Implementation:

• Algorithm: HS256 (HMAC-SHA256)
• Handler: Microsoft.IdentityModel.JsonWebTokens.JsonWebTokenHandler
• Validation: Token signature, expiration, and malformed token checks

Migration control

CLEAR_DATABASE=true

• Required: No
• Default: false
• Effect: If set to true, drops and recreates the database during migrations
• Usage: Development and testing environments only
• Warning: Never use in production

ASP.NET Core configuration

ASPNETCORE_ENVIRONMENT=Development    # Development, Production, Staging
ASPNETCORE_URLS=http://0.0.0.0:8080  # Binding address and port
DOTNET_RUNNING_IN_CONTAINER=true     # Flag for container execution

Frontend variables (web/frontend)

The active website does not use the old Next.js/Prisma environment model. Its core runtime variables are:

API_BASE_URL=http://localhost:8080       # Base URL for the .NET API
SESSION_SECRET=<generated-secret>        # Cookie session signing secret
NODE_ENV=development                     # Standard Node runtime mode

Frontend variable details

API_BASE_URL

• Required: Yes for local development
• Default in code: http://localhost:8080
• Used by: web/frontend/app/lib/auth.server.ts
• Purpose: Routes website auth actions to the .NET API

SESSION_SECRET

• Required: Strongly recommended in all environments
• Default in local code path: dev-secret-change-me
• Used by: React Router cookie session storage in auth.server.ts
• Purpose: Signs and validates the website session cookie

NODE_ENV

• Required: No
• Typical values: development, production, test
• Purpose: Controls secure cookie behavior and runtime mode

SMTP configuration (backend)

Read by Infrastructure.Email/SmtpEmailProvider.cs for sending confirmation and account emails.

SMTP_HOST=mailpit                        # Required, no default
SMTP_PORT=1025                           # Optional, defaults to 587
SMTP_USERNAME=<username>                 # Optional, no default
SMTP_PASSWORD=<password>                 # Optional, no default
SMTP_USE_SSL=false                       # Optional, defaults to true
SMTP_FROM_EMAIL=noreply@thebiergarten.app # Required, no default
SMTP_FROM_NAME=The Biergarten App        # Optional, defaults to "The Biergarten"

• Implementation: Infrastructure.Email/SmtpEmailProvider.cs throws on startup if SMTP_HOST or SMTP_FROM_EMAIL is missing
• Local dev: point at the mailpit Docker service (SMTP on port 1025, web UI on http://localhost:8025)
• Production: point at a real provider (SendGrid, Mailgun, Amazon SES, and so on)

Docker-specific variables

SQL Server container

SA_PASSWORD=YourStrong!Passw0rd   # SQL Server SA password
ACCEPT_EULA=Y                     # Accept SQL Server EULA (required)
MSSQL_PID=Express                 # SQL Server edition (Express, Developer, Enterprise)

Password Requirements:

• Minimum 8 characters
• Uppercase, lowercase, digits, and special characters
• Maps to DB_PASSWORD for application containers

Environment file structure

Backend/Docker (web/ directory)

web/.env.example          # Template (tracked in Git)
web/.env.dev             # Development config (gitignored)
web/.env.test            # Testing config (gitignored)
web/.env.prod            # Production config (gitignored)

Setup:

cp web/.env.example web/.env.dev
# Edit web/.env.dev with your values

Legacy frontend variables

Variables for the archived Next.js frontend (archive/next-js-web-app/) have been removed from this active reference, since that app is retained for reference only and is not run as part of the active stack.

Docker Compose Mapping:

• web/docker-compose.dev.yaml → web/.env.dev
• web/docker-compose.test.yaml → web/.env.test
• web/docker-compose.prod.yaml → web/.env.prod

Variable reference table

Variable	Backend	Frontend	Docker	Required	Notes
DB_SERVER	✓		✓	Yes*	SQL Server address
DB_NAME	✓		✓	Yes*	Database name
DB_USER	✓		✓	Yes*	SQL username
DB_PASSWORD	✓		✓	Yes*	SQL password
DB_CONNECTION_STRING	✓			Yes*	Alternative to components
DB_TRUST_SERVER_CERTIFICATE	✓		✓	No	Defaults to True
ACCESS_TOKEN_SECRET	✓		✓	Yes	Access token signing
REFRESH_TOKEN_SECRET	✓		✓	Yes	Refresh token signing
CONFIRMATION_TOKEN_SECRET	✓		✓	Yes	Confirmation token signing
WEBSITE_BASE_URL	✓			Yes	Website URL for emails
SMTP_HOST	✓		✓	Yes	SMTP server host
SMTP_PORT	✓		✓	No	Defaults to 587
SMTP_USERNAME	✓		✓	No	SMTP auth username
SMTP_PASSWORD	✓		✓	No	SMTP auth password
SMTP_USE_SSL	✓		✓	No	Defaults to true
SMTP_FROM_EMAIL	✓		✓	Yes	Email sender address
SMTP_FROM_NAME	✓		✓	No	Defaults to The Biergarten
API_BASE_URL		✓		Yes	Website-to-API base URL
SESSION_SECRET		✓		Yes	Website session signing
NODE_ENV		✓		No	Runtime mode
CLEAR_DATABASE	✓		✓	No	Dev/test reset flag
ASPNETCORE_ENVIRONMENT	✓		✓	Yes	ASP.NET environment
ASPNETCORE_URLS	✓		✓	Yes	API binding address
SA_PASSWORD			✓	Yes	SQL Server container
ACCEPT_EULA			✓	Yes	SQL Server EULA
MSSQL_PID			✓	No	SQL Server edition
DOTNET_RUNNING_IN_CONTAINER	✓		✓	No	Container flag

* Either DB_CONNECTION_STRING OR the component variables (DB_SERVER, DB_NAME, DB_USER, DB_PASSWORD) must be provided.

Validation

Backend validation

Variables are validated at startup:

• Missing required variables (ACCESS_TOKEN_SECRET, REFRESH_TOKEN_SECRET, CONFIRMATION_TOKEN_SECRET, SMTP_HOST, SMTP_FROM_EMAIL, DB connection values) cause the application to fail with an InvalidOperationException
• No minimum length is enforced on the token secrets in code; the "minimum 32 characters" guidance above is a recommendation, not an enforced check

Frontend validation

The active website relies on runtime defaults for local development and the surrounding server environment in deployed environments.

• API_BASE_URL defaults to http://localhost:8080
• SESSION_SECRET falls back to a development-only local secret
• NODE_ENV controls secure cookie behavior

Example configuration files

.env.dev (backend/Docker)

# Database
DB_SERVER=sqlserver,1433
DB_NAME=Biergarten
DB_USER=sa
DB_PASSWORD=Dev_Password_123!

# JWT Authentication Secrets
ACCESS_TOKEN_SECRET=<generated-with-openssl>
REFRESH_TOKEN_SECRET=<generated-with-openssl>
CONFIRMATION_TOKEN_SECRET=<generated-with-openssl>
WEBSITE_BASE_URL=http://localhost:3000

# SMTP (Mailpit in dev)
SMTP_HOST=mailpit
SMTP_PORT=1025
SMTP_USE_SSL=false
SMTP_FROM_EMAIL=noreply@thebiergarten.app
SMTP_FROM_NAME=The Biergarten App

# Migration
CLEAR_DATABASE=true

# ASP.NET Core
ASPNETCORE_ENVIRONMENT=Development
ASPNETCORE_URLS=http://0.0.0.0:8080

# SQL Server Container
SA_PASSWORD=Dev_Password_123!
ACCEPT_EULA=Y
MSSQL_PID=Express

Frontend local runtime example

API_BASE_URL=http://localhost:8080
SESSION_SECRET=<generated-with-openssl>
NODE_ENV=development