Variables article

hugosite/content/posts/variable-management-django-upsun.md

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+title = 'Compile your Python code to Pycache on Upsun'
+date = 2024-08-08T09:00:00+02:00
+draft = false
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+
+## Why Upsun for Django?
+
+Upsun stands out as a comprehensive platform for Django developers that addresses many common pain points in Django deployment and development.
+
+- Ready-to-use services: Redis, PostgreSQL, Kafka, Elastic Search, Open Search and more
+- Environment cloning for testing and development (great for teams working together)
+- Infrastructure as code for version-controlled server setups
+- Local development boost through service tunneling
+- Integrated Blackfire profiling for performance optimization
+
+These features collectively create an ecosystem that streamlines Django development, from local coding to production deployment.
+
+## The Importance of Variable Management
+
+While Upsun's features are powerful, their effective use hinges on mastering variable management. Proper variable handling is crucial because it:
+- Prevents security breaches by keeping sensitive information out of your codebase
+- Maintains environment integrity, ensuring development doesn't interfere with production
+- Clarifies system architecture, making your project more maintainable
+- Reduces debugging time by minimizing configuration-related issues
+
+Consider this example of secure variable usage:
+```python
+# Insecure
+SECRET_KEY = "actual_secret_key_here"  # Exposed in code
+
+# Secure
+SECRET_KEY = os.environ.get("DJANGO_SECRET_KEY")  # Secured in environment
+```
+
+## Understanding Upsun's Variable System
+
+Upsun employs a hierarchical variable system that offers flexibility and security across different project scopes. Understanding this system is key to leveraging Upsun's full potential.
+
+Upsun uses three types of variables:
+1. Project variables: Apply across all environments in a project
+2. Environment variables: Specific to individual environments (e.g., development, staging, production)
+3. Application variables: Defined in `.upsun/config.yaml`, specific to each application
+
+These variables follow a precedence order: Environment > Project > Application. This hierarchy allows for fine-grained control over your configuration.
+
+For example, you might set a default DEBUG value in your application variables:
+```yaml
+# .upsun/config.yaml
+applications:
+    myapp:
+        variables:
+            env:
+                DEBUG: false
+```
+But then override it for a specific environment using the Upsun console or CLI.
+
+Upsun also provides `PLATFORM_*` variables that give you insights into your runtime environment. These are particularly useful for dynamic configuration:
+
+```python
+import json
+import base64
+
+relationships = json.loads(base64.b64decode(os.environ['PLATFORM_RELATIONSHIPS']))
+db_settings = relationships['database'][0]
+
+DATABASES = {
+    'default': {
+        'ENGINE': 'django.db.backends.postgresql',
+        'NAME': db_settings['path'],
+        'USER': db_settings['username'],
+        'PASSWORD': db_settings['password'],
+        'HOST': db_settings['host'],
+        'PORT': db_settings['port'],
+    }
+}
+```
+
+This setup automatically configures your database connection based on the current environment, eliminating the need for manual configuration across different deployments.
+
+## Managing Sensitive Data: OPENAI_API_KEY
+
+Handling sensitive data, like API keys, requires extra care. Let's use the OPENAI_API_KEY as an example to illustrate best practices across different environments.
+
+1. Local Development:
+   Create a `.env` file (remember to add it to `.gitignore`):
+   ```
+   OPENAI_API_KEY=your_api_key_here
+   ```
+
+   Then in `settings.py`:
+   ```python
+   from dotenv import load_dotenv
+   load_dotenv()
+   OPENAI_API_KEY = os.getenv('OPENAI_API_KEY')
+   ```
+
+   This approach keeps your key secure during local development.
+
+2. Upsun Environments:
+   Use the Upsun CLI to securely set the variable:
+   ```
+   upsun variable:create --level environment --name OPENAI_API_KEY --value your_api_key
+   ```
+
+   This command sets the variable for a specific environment, allowing you to use different keys for staging and production.
+
+3. Accessing in Django:
+   ```python
+   from django.conf import settings
+   import openai
+
+   openai.api_key = settings.OPENAI_API_KEY
+   ```
+
+   By accessing the key through settings, you maintain a consistent interface regardless of where the key is stored.
+
+## Best Practices and Tips
+
+1. Differentiate Environments:
+   Use `PLATFORM_ENVIRONMENT` and `PLATFORM_ENVIRONMENT_TYPE` to adjust settings based on the current environment:
+   ```python
+   import os
+
+   env_name = os.getenv('PLATFORM_ENVIRONMENT', 'local')
+   env_type = os.getenv('PLATFORM_ENVIRONMENT_TYPE', 'development')
+
+   if env_type == 'production':
+       DEBUG = False
+       ALLOWED_HOSTS = ['www.example.com']
+   elif env_type == 'staging':
+       DEBUG = True
+       ALLOWED_HOSTS = ['staging.example.com']
+   else:
+       DEBUG = True
+       ALLOWED_HOSTS = ['localhost', '127.0.0.1']
+
+   # You can also use env_name for more specific environment handling
+   if env_name == 'main':
+       # Special configuration for the main environment
+       pass
+   ```
+
+   This approach allows you to maintain a single settings file while still customizing behavior per environment type and name.
+
+2. Use Upsun-provided variables:
+   ```python
+   import os
+   import json
+   import base64
+
+   # Access the application configuration
+   app_config = json.loads(base64.b64decode(os.environ['PLATFORM_APPLICATION']).decode('utf-8'))
+
+   # Use PLATFORM_PROJECT_ENTROPY for secret key
+   SECRET_KEY = os.environ['PLATFORM_PROJECT_ENTROPY']
+
+   # Set the static root using PLATFORM_APP_DIR
+   STATIC_ROOT = os.path.join(os.environ['PLATFORM_APP_DIR'], 'static')
+
+   # Configure database using PLATFORM_RELATIONSHIPS
+   if os.environ.get('PLATFORM_RELATIONSHIPS'):
+       relationships = json.loads(base64.b64decode(os.environ['PLATFORM_RELATIONSHIPS']).decode('utf-8'))
+       db_settings = relationships['database'][0]
+       DATABASES = {
+           'default': {
+               'ENGINE': 'django.db.backends.postgresql',
+               'NAME': db_settings['path'],
+               'USER': db_settings['username'],
+               'PASSWORD': db_settings['password'],
+               'HOST': db_settings['host'],
+               'PORT': db_settings['port'],
+           }
+       }
+   ```
+
+3. Handle Sensitive Data:
+   For highly sensitive information, use Upsun's encrypted variables:
+   ```
+   upsun variable:create --level project --name SUPER_SECRET --value "sensitive_data" --sensitive true
+   ```
+
+   Access these variables through `PLATFORM_VARIABLES`:
+   ```python
+   import os
+   import json
+   import base64
+
+   platform_vars = json.loads(base64.b64decode(os.environ['PLATFORM_VARIABLES']).decode('utf-8'))
+   SUPER_SECRET = platform_vars.get('SUPER_SECRET')
+   ```
+
+4. Debug Variable Issues:
+   - Always redeploy after changing variables
+   - Use `upsun ssh` to check environment variables directly on the server
+   - Review Upsun's activity log for recent changes
+   - Use `PLATFORM_TREE_ID` for build-specific logging or debugging
+
+## Conclusion
+
+Upsun's variable management system is a powerful tool for creating flexible, secure, and maintainable Django deployments. By effectively using project, environment, and application variables, you can create a robust configuration setup that adapts to different environments while keeping sensitive data secure.
+
+Remember these key points:
+- Leverage Upsun's variable hierarchy for flexible configurations
+- Keep sensitive data out of your codebase
+- Use `PLATFORM_*` variables for environment-specific settings
+- Regularly audit and rotate sensitive variables
+
+Mastering Upsun's variable management not only enhances your project's security but also streamlines your development workflow. It allows you to focus on what truly matters - building exceptional Django applications - while Upsun handles the intricacies of deployment and environment management.
+
+Thanks for reading the tutorial! If you have any questions, my email address is [email protected] and you can [find me on LinkedIn](https://www.linkedin.com/in/roberttdouglass/). There is also an [Upsun Discord forum](https://discord.gg/PkMc2pVCDV) where I hang out, and you're welcome to find me there.