Add, Remove, or Replace Content Distributed by CloudFront

CloudFront offers a robust and scalable content delivery service, allowing businesses to efficiently distribute files and resources to users worldwide. Managing content effectively in CloudFront requires understanding how to add, update, or remove content within distributions. This article explores best practices and strategies for optimizing CloudFront content management.

Adding Content to CloudFront

To distribute new content using CloudFront, you must upload files to one of the origins specified in your distribution configuration. Origins typically include Amazon S3 buckets or custom origins hosted on your domain.

Key Considerations:

• Ensure the correct path pattern is defined in your cache behavior.

• Example: If your path pattern is set to *.html, CloudFront will only distribute .html files. Other file types, such as .jpg, will not be served unless a cache behavior specifically includes them.

Best Practice:

• Explicitly define cache behaviors for all required file types to prevent unintended exclusions.

Updating Content with File Versioning

When you need to update existing content, using version identifiers in file or folder names provides better control over what CloudFront serves.

Benefits of File Versioning:

• Eliminates the need to wait for cached objects to expire.

• Avoids the cost associated with object invalidation.

Example:

• Instead of replacing style.css, upload a new version as style_v2.css.

• Update references in your code to point to the new version.

Additional Recommendation:

• Even when using versioning, set an expiration date for cached content to manage long-term cache control.

Removing Content from CloudFront

To stop distributing specific files:

1. Remove files from the origin.

2. Consider cache expiration timelines. Files remain in the edge cache until they expire.

Immediate Removal Options:

• Invalidate Files: Use the CloudFront console or API to invalidate specific objects.

• File Versioning: Switch to serving a different version with a unique name.

Note: Invalidating multiple URL formats (with and without trailing slashes) may increase costs if you exceed the free monthly allowance.

Customizing URLs in CloudFront

Using a Custom Domain Name:

• Replace the default CloudFront domain with a custom domain, such as example.com, to improve branding.

• Example URL: https://example.com/images/pic.jpg

Trailing Slash Consistency:

• Choose a single URL format (with or without a trailing slash) and use it consistently.

• Example:

  • Use either https://example.com/images/ or https://example.com/images across your site.

Why It Matters: CloudFront treats different URL formats as unique. Consistency avoids unnecessary invalidation and cost.

Restricting Access with Signed URLs

For secure content delivery, use signed URLs or cookies to restrict access based on authentication or time limits.

Example:

• A signed URL may allow access to a video file for a set time period or from specific IP addresses.

• Implementation details are available in the CloudFront documentation on Serving Private Content.

Conclusion

Managing content distribution in CloudFront involves careful planning around cache behaviors, versioning, and URL management. By following these best practices, you can ensure efficient delivery, minimize unnecessary costs, and provide an optimized user experience.