> ## Documentation Index
> Fetch the complete documentation index at: https://docs.backant.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Configuration

> Environment variables and database configuration for your BackAnt project.

Every BackAnt project ships with a `.env` file at the project root. This file is loaded at startup by `python-dotenv` and mapped to the `Environment` class in `api/startup/Environment.py`.

## Default `.env`

```env theme={null}
POSTGRES_USER=postgres
POSTGRES_PASSWORD=test
POSTGRES_DB=postgres
DB_URL=postgres
CLEAR_DB=False
FLASK_APP=app.py
FLASK_ENV=development
TESTING=False
```

<Warning>
  Never commit real credentials to version control. Add `.env` to `.gitignore` and use secrets management in production.
</Warning>

## Database variables

| Variable            | Description                             | Default                          |
| ------------------- | --------------------------------------- | -------------------------------- |
| `POSTGRES_USER`     | PostgreSQL username                     | `postgres`                       |
| `POSTGRES_PASSWORD` | PostgreSQL password                     | `test`                           |
| `POSTGRES_DB`       | Database name                           | `postgres`                       |
| `DB_URL`            | Hostname of the PostgreSQL server       | `postgres` (Docker service name) |
| `CLEAR_DB`          | Drop and recreate all tables on startup | `False`                          |

`DB_URL` should be set to `postgres` when running inside Docker Compose (the service name resolves as a hostname), and `localhost` when running Flask directly outside of Docker.

<Warning>
  Set `CLEAR_DB=True` only during development. It drops all tables on every restart.
</Warning>

## Flask variables

| Variable    | Description                                   | Default       |
| ----------- | --------------------------------------------- | ------------- |
| `FLASK_APP` | Entry point for Flask                         | `app.py`      |
| `FLASK_ENV` | `development` enables debug mode and reloader | `development` |
| `TESTING`   | Enables test mode in Flask                    | `False`       |

## AWS / S3 variables

These are used by the built-in `AWSClient` in `api/apis/aws/AWSClient.py`.

| Variable        | Description           |
| --------------- | --------------------- |
| `S3_ACCESS_KEY` | AWS access key ID     |
| `S3_SECRET_KEY` | AWS secret access key |

## AWS Cognito variables

Used when integrating Cognito for authentication.

| Variable                    | Description                             |
| --------------------------- | --------------------------------------- |
| `COGNITO_REGION`            | AWS region (e.g. `eu-central-1`)        |
| `COGNITO_USERPOOL_ID`       | Cognito User Pool ID                    |
| `COGNITO_APP_CLIENT_ID`     | Cognito App Client ID                   |
| `COGNITO_APP_CLIENT_SECRET` | Cognito App Client Secret               |
| `COGNITO_ACCESS_KEY_ID`     | IAM access key with Cognito permissions |
| `COGNITO_SECRET_ACCESS_KEY` | Corresponding IAM secret key            |

## Environment class

All variables are accessed at runtime via the `myEnvironment` singleton in `api/startup/Environment.py`. Never read `os.environ` directly — import from the singleton instead:

```python theme={null}
from startup.Environment import myEnvironment

db_url = myEnvironment.DB_URL
region = myEnvironment.COGNITO_REGION
```

## Local development without Docker

Set `DB_URL=localhost` and ensure PostgreSQL is running locally:

```env theme={null}
DB_URL=localhost
POSTGRES_USER=postgres
POSTGRES_PASSWORD=test
POSTGRES_DB=postgres
CLEAR_DB=False
```

Then run Flask directly:

```bash theme={null}
cd my-api
flask run
```