WSGI applications are required to return bytes.

Created by: GrahamDumpleton

This code looks suspect:

• https://github.com/fgallaire/wsgiserver/blob/master/wsgiserver.py#L2345

A WSGI application iterable is supposed to return byte strings for response body. If it returns Unicode strings it is an error.

A WSGI server is not meant to convert Unicode strings to byte strings automatically.

Thus concerned about what the code:

            for chunk in response:
                # "The start_response callable must not actually transmit
                # the response headers. Instead, it must store them for the
                # server or gateway to transmit only after the first
                # iteration of the application return value that yields
                # a NON-EMPTY string, or upon the application's first
                # invocation of the write() callable." (PEP 333)
                if chunk:
                    if isinstance(chunk, text_type):
                        chunk = chunk.encode('ISO-8859-1')
                    self.write(chunk)

is doing.