• I'm submitting a ...

• bug report
• feature request
• question about the decisions made in the repository

• What is the current behavior?
  The browser sends a request that contains both RANGE and IF-RANGE values. Note that the If-Range value is way in the past.

Range: bytes=32768-32768
If-Range: Tue, 21 Nov 2017 14:43:11 GMT

However, the CherryPy Server sends back "206 Partial Content" instead of sendong back the file content and status 200.

This violates the If-Range header specification

The If-Range HTTP request header makes a range request conditional: if the condition is fulfilled, the range request will be issued and the server sends back a 206 Partial Content answer with the appropriate body. If the condition is not fulfilled, the full resource is sent back, with a 200 OK status.

• If the current behavior is a bug, please provide the steps to reproduce and if possible a screenshots and logs of the problem.

The following can be replicated using Chrome or FF:

• Enable caching in the CherryPy server.
• Request a page with cached resources (e.g. JS or CSS files)
• Clear the browser cache.
• Press F5
• Only the HTML part is loaded, the "cached" files are missing and will cause a GET http://localhost:45101/jquery.js net::ERR_CONTENT_DECODING_FAILED in the browser console.

• What is the expected behavior?

The CherryPy server should check if the request contains the If-Range header. And if the condition is not fullfilled, send back the resource and status 200, instead of status 206.

• What is the motivation / use case for changing the behavior?

This is very annoying, because it prevents the page from loading / refreshing.
You have to do a hard-refresh (Ctrl-F5) to work-around this issue, which cannot be done on mobile devices.

• Other information (e.g. detailed explanation, stacktraces, related issues, suggestions how to fix, links for us to have context, e.g. stackoverflow, gitter, etc.)

This should probably be fixed in _serve_fileobj().

Request:

Response: