[Web-SIG] WSGI uses

[Phillip J. Eby]

At 11:50 PM 8/18/04 -0500, Ian Bicking wrote:
>I was playing around with making a WSGI server, and I'm starting to think 
>that some really neat stuff could be done with middleware.

Indeed.  In recent months, when I was refactoring peak.web to remove its 
dependency on Zope X3, I came up with a variant of the current WSGI 
interface as a strictly internal coupling mechanism for peak.web.  It 
turned out to be a delightfully simple way to connect internal 
components.  A peak.web user had previously complained about the difficulty 
of wrapping arbitrary postprocessing around pages, so I invented a more 
"functional" protocol for coupling peak.web components.  The main 
difference between it and WSGI now, was that it returned the status, 
headers, and iterator all in one tuple.  Tony Lownds proposed the write = 
start_response(status,headers) part, and I merged it with returning an 
iterator to form the new interface.  It's a reasonably lightweight API for 
both the server and application sides, but it's *remarkably* lightweight 
for middleware.