Static files

SymfonyCloud supports response compression using either gzip or Brotli if the following conditions are met:

• The request supports gzip or brotli;
• The file is served directly from disk, not passed through your application;
• The request is served with a cache expiration in the future.

If an incoming request meets the previous conditions and the file type is one of: html, javascript, json, pdf, postscript, svg, css, csv, plain text, or XML; the response is automatically compressed with the appropriate algorithm.

Alternatively, if a file with a .gz or .br extension exists, this file will be served instead of being compressed on the fly. This approach supports any file type and offers some CPU optimization.

Dynamic content

Compression is disabled for dynamic content due to a well known security issue. Applications can compress their own responses but they should not do it when responses include any-user specific information (such as session cookies) to prevent against the previously linked vulnerability. As a precautionary measure, we recommend against compressing dynamic content.