I needed a simple logarithmic based tag cloud where the frequency of the tags was weighted logarithmically. This means that lower frequency tags get dampened down into the same font size and higher frequency tags are popped out in a tag cloud.

def tag_weight(x):
    if x==None or x==0:
         x = 1
    return weight * math.log(x, math.e)

It is pretty simple. It protects against a None or 0 as putting either of those into the log function would result in a ValueError.

The 'weight' variable can be fixed or calculated and is a means to add a formula to the log output to make the tag cloud look good to a human eye when displayed on the page. I use the output of the tag_weight() function in the style attribute of li with with font-size and em.

You can see the results of this algorithm on this tag cloud.

I needed a simple logarithmic based tag cloud where the frequency of the tags was weighted logarithmically. This means that lower frequency tags get dampened down into the same font size and higher frequency tags are popped out in a tag cloud.

def tag_weight(x):
    if x==None or x==0:
         x = 1
    return weight * math.log(x, math.e)

It is pretty simple. It protects against a None or 0 as putting either of those into the log function would result in a ValueError.

The 'weight' variable can be fixed or calculated and is a means to add a formula to the log output to make the tag cloud look good to a human eye when displayed on the page. I use the output of the tag_weight() function in the style attribute of li with with font-size and em.

Disclaimer, I make most of my living working in Java and this blog is written in Python. Elliotte Rusty Harold writes after seeing Python 3 come out with little care for backwards compatibility:

Unless we're willing to make the hard choices and abandon the legacy as Python has, Java is doomed to the fate of C++ and Cobol: a tool for programmers with long white beards who grew up with the language and have learned all its arcana by gradual accretion and who spend their lives maintaining code written a decade or more ago.

Meanwhile a new generation of programmers will abandon Java in favor of more nimble modern languages like Python just as we abandoned C++ in our youth in favor of Java.

There are still an awful lot of systems written in Java that will need to be maintained; there is also a great deal of business logic in freeware and payware libraries that are used to ease the burden on development. I don't see that changing soon. I do agree it is frustrating to work in a language and see its limitations and clunkiness day after day after day.

A good rant none the less.

I am trying to set up this blog's software, which I wrote on python, on the Macbook as opposed to the old Vista desktop I wrote it on. No luck so far. Doubt i have the patience to fix all the compile and egg errors. It might be easier to rewrite the blog in lisp and upload it as one big .emacs file.

I decided to try and integrate my flickr feed into the blog somehow. After some cursory looking around it seemed using the Flickr Services and the flickrapi was the simplest way to achieve that. While this open style of API might enable Web 2.0, the cloud, and all other manner of new uses, for me I just wanted to put my latest flickr uploads on one page on my blog.

I used easy_install to put the flickrapi library on my dev machine and ISP's server. I got the api-key from flickr and since I haven't changed my user id to something more human readable it was a simple find as well.

 # get the list of photos from flickr
def get_flickr_photos(self):
    flickr = flickrapi.FlickrAPI(self.flickr_api_key, format='etree')
    photos = flickr.photos_search(user_id=self.flickr_user_id, per_page='50') # comes out as the _ElementInterface
    # parse out the XML and return an array of URLs
    # http://farm{farm-id}.static.flickr.com/{server-id}/{id}_{secret}_[mstb].jpg
    urls = []
    for image in photos.getchildren()[0]:
        img = {}
        src = 'http://farm%s.static.flickr.com/%s/%s_%s_m.jpg' %  (image.attrib['farm'], image.attrib['server'], image.attrib['id'], image.attrib['secret'])
        url = 'http://www.flickr.com/photos/%s/%s/' % (self.flickr_user_id, image.attrib['id'])
        img['src'] = src
        img['title'] = image.attrib['title']
        img['url'] = url
        urls.append(img)
    return urls

Turned out to be simpler than I expected. The hardest part was working out what the hell I was getting back, Python interfaces can be quite opaque to what data they are carrying. I finally found ElementTree.toString(_ElementInterface) so I could see what I was getting and how far down it I had to drill to get the information I wanted.

You can see the results on the photography page. I made it permanently accessible by the camera icon at the top of the page.

easy_install SQLObject==0.9.0

Was trying to get a result set that was semi-random with only three result coming back using sqlobject. I over-engineered my first attempt into a mess, and sat back to think for a while. In the end I came up with:

 def randResultSet():
    resultSet = Table.select()
    count = resultSet.count()
    upper_bound = random.randint(3,count)
    lower_bound = upper_bound - 3;
    return resultSet[lower_bound: upper_bound]

Two very cool things. SQLObject's SelectResults object on the count() function does a quick query with COUNT rather than loading all the results the select() function returned. Which makes the count call cheap.

SQLObject loads the results lazily anyway, only doing the query when you actually want them. When combined with python's splicing this makes a semi-random result set pretty simple. With some fudging of the orderBy argument and reversed() it is random enough for human eyes.

For phoenix eats out I had to do an internal redirect with CherryPy based on the URL that was coming in, but only for the index page. I did it for all other cases in Apache, but decided with the index page to do it using Turbogears.

The main issue, which took me a while to workout, was that I was running CherryPy as a server locally on my dev machine, but in production I am using mod_proxy with apache. CherryPy gives you quick and easy access to the request headers as a dict, so it is easy to punch out and see what is going on. In my dev environment I set up phoenixeatsout.com in my /etc/hosts to resolve to localhost and wrote:

 if cherrypy.request.headers.get("Host") == 'www.phoenixeatsout.com':
    raise cherrypy.InternalRedirect('/restaurants/')

Which worked fine when I was running CherryPy as the http server. With mod_proxy that doesn't work as the host is always localhost:8000 or whatever host and port you are running CherryPy on that Apache connects to through mod_proxy. After pumping out the headers to the main page I changed it in production to:

reqHost = cherrypy.request.headers.get("X-Forwarded-Host")
if reqHost == 'www.phoenixeatsout.com':
    raise cherrypy.InternalRedirect('/restaurants/')

Because it is an internal redirect it slides to that controller without changing the URL to the user's eye. Quite neat.

More And fwiw the point versioning of the South Sea Republic, Cam Riley and Phoenix Eats Out codebase has gone from 1.3.64 to 1.4.0.