The server in http.server currently doesn't support HTTP compression.

I propose to implement it in the method send_head() of SimpleHTTPRequestHandler this way : for each GET request, if the request header "Accept-Encoding" is present and includes "gzip" among the possible compression schemes, and if the Content-Type determined by the file extension is in a list compressed_types, then the server sends the "Content-Encoding" response header to "gzip" and send_head() returns a file object with the gzipped value.

compressed_types is an attribute of the SimpleHTTPRequestHandler class and is set by default to ["text/plain", "text/html", "text/css", "text/xml", "text/javascript", "application/javascript", "application/json"].

The implementation is very simple (a few lines of code).

I also propose to modify mimetypes to add the mapping of extension ".json" to "application/json".

I will make a Pull Request on the CPython Github site with these changes.