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The auction for Inga's painting has begun! You can find the auction here:

Check it out!

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Aesthetic-Mindset reached 100,000 hits sometime earlier today. The site has been up since February 6th of this year. Congratulations are in order for Justin and I!

I played around with this as a potential hack for CherryPy 3. It's WSGI middleware for adding almost-transparent "internal redirect" capabilities to any WSGI application.

My operating theory was that anyone writing a WSGI app that does not already have an internal-redirect feature was probably using HTTP redirects (302, 303, or 307) to do nearly the same thing. This middleware simply waits for a 307 response status and performs the redirection itself within the same request, without informing the user-agent.

This should be OK because 307 isn't normally cacheable anyway, and some versions of IE don't bother to ask the user as the spec requires already, so it just duplicates an existing browser bug. I could have used a custom HTTP code like 399, but if that ever leaked out to the UA (because someone forgot to enable the middleware) then the UA should fall back to "300 Multiple Choices", which didn't seem like a good fit. At least by using 307, the fallback should be appropriate, if not graceful.

Here's the code, which could probably use some improvements:

"""WSGI middleware which performs "internal" redirection."""

import StringIO


class _Redirector(object):

    def __init__(self, nextapp, recursive=False):
        self.nextapp = nextapp
        self.recursive = recursive

        self.location = None
        self.write_proxy = None
        self.status = None
        self.headers = None
        self.exc_info = None

        self.seen_paths = []

    def start_response(self, status, headers, exc_info):
        if status[:3] == "307":
            for name, value in headers:
                if name.lower() == "location":
                    self.location = value
                    break
        self.status = status
        self.headers = headers
        self.exc_info = exc_info
        return self.write

    def write(self, data):
        # This is only here for silly apps which call write.
        if self.write_proxy is None:
            self.write_proxy = self.sr(self.status, self.headers, self.exc_info)
        self.write_proxy(data)

    def __call__(self, environ, start_response):
        self.sr = start_response

        nextenv = environ.copy()
        curpath = nextenv['PATH_INFO']
        if nextenv.get('QUERY_STRING'):
            curpath = curpath + "?" + nextenv['QUERY_STRING']
        self.seen_paths.append(curpath)

        while True:
            # Consume the response (in case it's a generator).
            response = [x for x in self.nextapp(nextenv, self.start_response)]

            if self.location is None:
                # No redirection required; complete the response normally.
                self.sr(self.status, self.headers, self.exc_info)
                return response

            # Start with a fresh copy of the environ and start altering it.
            nextenv = environ.copy()
            nextenv['REQUEST_METHOD'] = 'GET'
            nextenv['CONTENT_LENGTH'] = '0'
            nextenv['wsgi.input'] = StringIO.StringIO()
            nextenv['redirector.history'] = self.seen_paths[:]

            # "The [Location response-header] field value
            # consists of a single absolute URI."
            (nextenv["wsgi.url_scheme"],
             nextenv["SERVER_NAME"],
             path, params,
             nextenv["QUERY_STRING"], frag) = urlparse(self.location)

            if frag:
                raise ValueError("Illegal #fragment in Location response "
                                 "header %r" % self.location)

            if params:
                path = path + ";" + params

            # Assume 'path' is already unquoted according to
            # <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec5.html#sec5.1.2">http://www.w3.org/Protocols/rfc2616/rfc2616-sec5.html#sec5.1.2</a>
            if path.lower().startswith(environ['SCRIPT_NAME'].lower()):
                nextenv["PATH_INFO"] = path[len(environ['SCRIPT_NAME']):]
            else:
                raise ValueError("Location response header %r does not "
                                 "match current SCRIPT_NAME %r"
                                 % (self.location, environ['SCRIPT_NAME']))

            # Update self.seen_paths and check for recursive calls.
            curpath = nextenv['PATH_INFO']
            if nextenv.get('QUERY_STRING'):
                curpath = curpath + "?" + nextenv['QUERY_STRING']
            if curpath in self.seen_paths:
                raise RuntimeError("redirector visited the same URL twice: %r"
                                   % curpath)
            else:
                self.seen_paths.append(curpath)

            # Reset self for the next iteration
            self.location = None
            self.write_proxy = None
            self.status = None
            self.headers = None
            self.exc_info = None


def redirector(nextapp, recursive=False):
    """WSGI middleware which performs "internal" redirection.

    Whenever the next application sets a response status of 307 and
    provides a Location response header, this component will not pass
    that response on to the user-agent; instead, it parses the URI
    provided in the Location response header and calls the same
    application again using that URI. The following entries in the
    WSGI environ dict may be modified when redirecting: wsgi.url_scheme,
    SERVER_NAME, PATH_INFO, QUERY_STRING. REQUEST_METHOD is always
    set to 'GET', so any desired parameters must be supplied as
    query string arguments in the Location response header.
    The wsgi.input entry will always be reset to an empty StringIO,
    and CONTENT_LENGTH will be set to 0.

    If 'recursive' is False (the default), each new target URI will be
    checked to see if it has already been visited in the same request;
    if so, a RuntimeError is raised. If 'recursive' is True, no check
    is made and therefore no such errors are raised.
    """
    def redirect_wrapper(environ, start_response):
        ir = _Redirector(nextapp, recursive)
        return ir(environ, start_response)
    return redirect_wrapper

Ok, I was just reading my Mom's blog and she used the word "blogosphere". I'm not sure if I should be impressed or scared.

Link: http://www.ambrosiaempire.com/vegan/2006/11/today-is-painting-day.html

My friend Inga of Miami Vegan has decided to do a painting of one of my photographs. She started today and will be publishing her progress along the way from the charcoal schetching to the finishing touches.

I've never had anyone reproduce my art like this and I am really excited to see it at his happens. If you're interested you might want to peak over at her blog every couple of days as she works on the piece.

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I had a pretty gnarly arrhythmia today about an hour ago. No big deal, it was a "perfectly normal" thing that happens to me from time to time. It got me thinking though about a few things though. I started thinking about the whole DNR (Do Not Resuscitate) issue that I've pondered for a few years. Don't freak out, I'm currently still in the "Do Resuscitate" group. Along with that I started pondering the fact that I haven't had a medical bracelet for over a decade, and that I should probably get a new one in case I am unconscious when the inevitable happens.

So in my ever-pondering everything ways, my mind abandoned that nicer looking pendant and now I'm considering just getting the stupid info tattooed on my chest. And if you think I'm being facetious, well, then you don't know me very well. Also, this way if I finally make up my mind about the DNR thing, I can just have the tattoo amended with that info as well as all my other stuff. Hmmm.

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My entire goal in life right now is to locate and consume a 20oz bottle of Mountain Dew. ugh.

One of my closest friends had a health scare last night and ended up in the ER, then to be admitted to the hospital overnight. Out of respect to privacy I don't feel a need to give a name or what happened. Friend is feeling much better this morning, and I thank God for that. Friend still has some tests and such, but I'm guessing that friend will be released from the hospital this afternoon sometime.

I love you, my friend.

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