Ian Lewis' Blog

Google Wave BOF

2009-06-03T00:08:24Z

I attended the Google Wave BOF (Birds of a Feather, A gathering of people with similar interests). It was a good time for folks with Google Wave accounts to show it off to folks who can't sign into it yet. It originally was going to be about 25 people but due to popular demand the location had to be moved, and it went up to about 40 people. Lots of folks were interested in hearing about Google Wave as a new collaborative platform.

id:a2c mentioned my 'debuggy' robot that I created to show events as they get fired by Google Wave. Below is me showing off debuggy at the Googleplex. I got a very tepid response from the folks at the hackathon. I seemed to get a better response from people at the BOF. I'll talk more about debuggy in a later post.

As it is, currently it was hard for most people to visualize how they would use the tool for daily work but everyone seemed interested in the possibilities and it was recieved warmly. Looking forward to future releases of Google Wave!

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Original post blogged on b2evolution.

Google IO 2009

2009-06-01T05:57:11Z

This year I attended Google IO and had so much fun that I think I'll have to break it up into several blog posts. Google IO is held in San Francisco and is the #1 Google event of the year. About 4000 or so developers attended the event which was held in the Moscone West Convention Center. In this post I'll kind of give the history of the events leading up to the event and some context.

One day in late January or so, Google announced that registration for this year's Google IO was open and there was a subsequent conversation on twitter that ensued which led to id:tmatsuo, id:a2c, id:voluntas, myself, and several others proclaiming they were going to attend this year's event.

I found out that the office of one of my old classmates, Bob Ippolito, is close to the event so I sort of jokingly invited myself and id:tmatsuo to stay at his office. You might know Bob as the co-founder and CTO of a company called MochiMedia, or as the author of numerous pieces of well used free software such as simplejson, MochiWeb, MochiKit, or PyObjC or as the coiner of the phrase JSONP (Note the date of the blog post). He has consistently gotten into things before they become big, including technologies such as json, erlang, Non-RDBM databases and often gives talks about them which essentially give you key insights into the future of web programming.

ded by offering to let me and id:tmatsuo stay at his apartment. However, when it came close to the event Bob realized that he was going to be at another conference for Flash developers in Boston, which meant that we would only have one day where we were both in San Francisco. Bummer! But he let us stay at his house even though he wasn't going to be there saving us a lot of money. He was very gracious.

Unfortunately, a few folks such as id:voluntas couldn't go to the event because of overreactions by their employers to the outbreak of swine flu but almost everyone that did go arrived in San Francisco on May 26th. I'll continue in a later blog post!!

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Original post blogged on b2evolution.

Tokyo Barcamp 2009

2009-05-16T13:18:05Z

Today I participated in Tokyo Barcamp 2009. From the Tokyo Barcamp website:

Tokyo BarCamp 2009 will be a day of workshops, presentations and discussions on a wide variety of topics related to technology and how it affects our lives.

I was a little skeptical about how organized barcamp would be when I decided to participate but it became very cool and conductive to discussing ideas. It especially gave people a good opportunity to think about the future of the web and the internet and various other topics such as "music in virtual worlds" and "eco living".

Discussions I participated in were as follows:

Mobile Browsers

Mobile browsers and their history and where they may be headed in the future. Discussion headed up by LonelyBob

Natural Language Parsing

A presentation and discussion about parsing language and getting a data in a unified format regardless of language (English, Japanese etc.) and regardless of language parsing method. The presentation was by Kim Ahlström from Smart.fm. He introduced Cereling which is a language parsing unifier/engine he is working on at Smart.fm and they are planning to Open Source. Unfortunately it's also apparently written in Ruby.

Hacker Space

By far the most interesting idea that came out of barcamp was the idea of hacker spaces where folks can get together and share ideas as well as have a space to try new things and experiment. There was a lot of interest in the Hacker Space concept and creating one in Tokyo. We even created a website already at Tokyo Hacker Space.

We also learned that there exists a Hacker Space in Tokyo already called 4ncho5la6 (Anchorlab). Some folks from the barcamp are planning to go out there and check it out. We want to see what they did and what we can learn from them and perhaps collaborate on membership and events. Interestingly, the lab is headed by Daito Manabe who is famous for his "Face Visualizer" video on Youtube.

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Original post blogged on b2evolution.

Connecting Sortables in jQuery UI

2009-04-22T01:26:41Z

jQuery has a UI framework called jQueryUI which provides a number of UI controls and widgets that you can use to create cool user interfaces. I've been using jQueryUI a fair bit for work recently and wanted to share a pretty cool feature that jQueryUI has.

jQueryUI has a widget called a sortable which is just a list of sortable dom elements. It allows you to drag the items around and resort them in a list. Options are passed in an object that you give to the sortable constructor/initializer. You can initialize a sortable like so:

$('#my-list').sortable({
  axis: 'x'
});

In this case the options object and contained "axis" option are optional but it gives you a good idea what a widget initializer looks like.

jQueryUI also has a draggable widget which allows you to easily create draggable items. This draggable can also be connected to a sortable object so you can drag an object onto a sortable widget.

$('#my-item').draggable({
  connectToSortable: '#my-list'
});

jQueryUI also allows you to connect sortables to each other which creates the potential for some interesting user interfaces.

$('#my-list').sortable({
  connectWith: '#my-other-list'
});

You can even connect the sortables together so you can drag items back and forth between the sortables:

$('#my-list').sortable({
  connectWith: '#my-other-list'
});

$('#my-other-list').sortable({
  connectWith: '#my-list'
});

DEMO >>

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Original post blogged on b2evolution.

Unreadable

2009-04-01T05:07:48Z

What is it about some C programmers that makes them write code that looks like this:

if(len<16) {
  for(k=start;k<start+len;k+=j) {
    j=1;x=V[I[k]+h];
    for(i=1;k+i<start+len;i++) {
      if(V[I[k+i]+h]<x) {
        x=V[I[k+i]+h];
        j=0;
      };
      if(V[I[k+i]+h]==x) {
        tmp=I[k+j];I[k+j]=I[k+i];I[k+i]=tmp;
        j++;
      };
    };
    for(i=0;i<j;i++) V[I[k+i]]=k+j-1;
    if(j==1) I[k]=-1;
  };
  return;
};

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Original post blogged on b2evolution.

Transactions on Appengine

2009-03-18T15:44:52Z

The way to store data on Appengine is with Google's BigTable Datastore which has support for transactions. However, the transactions are quite limited in that,

You can only execute callables inside transactions. Which means you basically call run_in_transaction() on a function. This can sometimes be a pain but can generally be worked around with decorators and the like.
def my_update_function():
# Some update code here
ent.put()

run_in_transaction(my_update_function)
You can only update entities in the same entity group. This means all entities must be in the same ancestor tree. This can make updating entities with various relationships hard or impossible to do in a general way in a transaction.

You cannot do filters in a transaction. This means you cannot do any kind of select, period. This means you cannot do the following:

class ModelA(db.Model):
  pass

class ModelB(db.Model):
  modela = ReferenceProperty(ModelA)

def update_func():
  # Sorry this won't work
  modelas = ModelA.all()

  # This is the only thing that works
  modela = ModelA.get_by_id(123)

  # Jeez, you can't do this either!
  modelb = ModelB.filter('modela =', modela)

You can only do gets based on the key of an entity. Which means if you have a relationship like the one above you need to be able to derive the key to ModelB given the key for ModelA. And since you cannot chose numeric keys with which to save entities (numeric keys are always assigned), you will need to assign key names for both entities.

All this makes transactions a bit of a pain in Appengine but workable if you put a bit of effort into it. In the end you'll want to use key names for most every entity that matters as current backup solutions for Appengine rely on key names to maintain the keys of entities when backing up and restoring. It wouldn't be to fun if all the urls for an entity that had numeric ids changed after restoring the data from a backup.

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Original post blogged on b2evolution.

Jaiku on Appengine

2009-03-15T14:52:31Z

Yesterday Google's Twitter-like service, Jaiku was released as open source running on Google Appengine so I decided to take it for a spin. It has a lot of neat parts like XMPP and google contacts integration, but what I'm interested in most is how it implements it's publisher/subscriber model.

I brought the code down from svn and tried to follow the instructions, but I got a "No module named django" error. One of the problems currently with appengine is that you have a limit of 1000 files you can upload. Because of this limit when deploying jaiku you need to zip a bunch of libraries into a zip file and use zipimport. Accordingly you have to prevent the source files from being uploaded because you get an error saying you can't upload more than 1000 files.

The problem there is that the newest (1.1.9) SDK prevents you from loading modules and/or accessing files that are specified in the skip-files directive in your app.yaml. This prevented me from importing django because it's a zipped module.

At first I tried just zipping the files up using the zip_all command in the Makefile (make zip_all) but I still got the same error so I just commented out the relevant parts in app.yaml.

skip_files: |

 ^(.*/)?(

 (app\.yaml)|

 (app\.yml)|

 (index\.yaml)|

 (index\.yml)|

 (#.*#)|

 (.*~)|

 (.*\.py[co])|

 (.*/RCS/.*)|

 # (\..*)|

 # (manage.py)|

 # (google_appengine.*)|

 # (simplejson/.*)|

 # (gdata/.*)|

 # (atom/.*)|

 # (tlslite/.*)|

 # (oauth/.*)|

 # (beautifulsoup/.*)|

 # (django/.*)|

 # (docutils/.*)|

 # (epydoc/.*)|

 # (appengine_django/management/commands/.*)|

 # (README)|

 # (CHANGELOG)|

 # (Makefile)|

 # (bin/.*)|

 # (images/ads/.*)|

 # (images/ext/.*)|

 # (wsgiref/.*)|

 # (elementtree/.*)|

 # (doc/.*)|

 # (profiling/.*)

 )$

From there it should have worked but I got an error about the pstats module. That just happened to not be installed on my machine so installed python-profiler and Jaiku ran from there.

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Original post blogged on b2evolution.

Werkzeug and reverse urls

2009-03-14T01:57:52Z

I wanted to impove a Google Appengine application that a friend of mine created (ほぼ汎用イベント管理ツール(jp)) and noticed that he was redirecting directly to urls. He is using Werkzeug to handle url routing so I wondered if there was a method for generating urls from a name like you can in Django.

It turns out you can but you give it an endpoint name rather than a url name.

urls.py

from werkzeug.routing import Map, Rule, RuleTemplate, Submount, EndpointPrefix

resource = RuleTemplate([
  Rule('/${name}/', endpoint='${name}_index'),
  Rule('/${name}/create/', endpoint='create_${name}'),
  Rule('/${name}/update/<string:${var}>/', endpoint='update_${name}'),
  Rule('/${name}/delete/<string:${var}>/', endpoint='delete_${name}'),
])

url_map = Map([
  Rule('/', endpoint='index'),
  Rule('/<string:slug>/', endpoint='project_or_event'),
  Rule('/form/<string:key>/<string:slug>/', endpoint='form'),
  Submount('/account', [
    Rule('/', endpoint='account_index'),
    Rule('/create/', endpoint='create_account'),
    Rule('/update/', endpoint='update_account'),
    Rule('/delete/', endpoint='delete_account'),
    Rule('/event/cancel/<string:slug>/', endpoint='event_cancel'),
  ]),
  EndpointPrefix('admin_', [
    Submount('/admin', [
      resource(name='account', var='email'),
      resource(name='project', var='slug'),
      resource(name='event', var='slug'),
      resource(name='program', var='slug'),
      resource(name='application', var='slug'),
    ]),
  ])
])

views.py

from werkzeug redirect as wredirect
from urls import url_map

def reverse(**kwargs):
  c = url_map.bind('')
  return wredirect(c.build(**kwargs))

...
   return reverse('form', dict(key=key, slug=slug))
...

You need to give the build function a full endpoint. in the above example you can have endpoints like admin_create_${name} where ${name} is the name of a resource. This would need to be filled in when passing it to build.

...
  return reverse('admin_create_event')
...

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Original post blogged on b2evolution.

	$('#my-list').sortable({
	connectWith: '#my-other-list'
	});

	$('#my-other-list').sortable({
	connectWith: '#my-list'
	});

	if(len<16) {
	for(k=start;k<start+len;k+=j) {
	j=1;x=V[I[k]+h];
	for(i=1;k+i<start+len;i++) {
	if(V[I[k+i]+h]<x) {
	x=V[I[k+i]+h];
	j=0;
	};
	if(V[I[k+i]+h]==x) {
	tmp=I[k+j];I[k+j]=I[k+i];I[k+i]=tmp;
	j++;
	};
	};
	for(i=0;i<j;i++) V[I[k+i]]=k+j-1;
	if(j==1) I[k]=-1;
	};
	return;
	};

	def my_update_function():
	# Some update code here
	ent.put()

	run_in_transaction(my_update_function)

	class ModelA(db.Model):
	pass

	class ModelB(db.Model):
	modela = ReferenceProperty(ModelA)

	def update_func():
	# Sorry this won't work
	modelas = ModelA.all()

	# This is the only thing that works
	modela = ModelA.get_by_id(123)

	# Jeez, you can't do this either!
	modelb = ModelB.filter('modela =', modela)

	skip_files: \|
	^(.*/)?(
	(app\.yaml)\|
	(app\.yml)\|
	(index\.yaml)\|
	(index\.yml)\|
	(#.*#)\|
	(.*~)\|
	(.*\.py[co])\|
	(./RCS/.)\|
	# (\..*)\|
	# (manage.py)\|
	# (google_appengine.*)\|
	# (simplejson/.*)\|
	# (gdata/.*)\|
	# (atom/.*)\|
	# (tlslite/.*)\|
	# (oauth/.*)\|
	# (beautifulsoup/.*)\|
	# (django/.*)\|
	# (docutils/.*)\|
	# (epydoc/.*)\|
	# (appengine_django/management/commands/.*)\|
	# (README)\|
	# (CHANGELOG)\|
	# (Makefile)\|
	# (bin/.*)\|
	# (images/ads/.*)\|
	# (images/ext/.*)\|
	# (wsgiref/.*)\|
	# (elementtree/.*)\|
	# (doc/.*)\|
	# (profiling/.*)
	)$

	from werkzeug.routing import Map, Rule, RuleTemplate, Submount, EndpointPrefix

	resource = RuleTemplate([
	Rule('/${name}/', endpoint='${name}_index'),
	Rule('/${name}/create/', endpoint='create_${name}'),
	Rule('/${name}/update/<string:${var}>/', endpoint='update_${name}'),
	Rule('/${name}/delete/<string:${var}>/', endpoint='delete_${name}'),
	])

	url_map = Map([
	Rule('/', endpoint='index'),
	Rule('/<string:slug>/', endpoint='project_or_event'),
	Rule('/form/<string:key>/<string:slug>/', endpoint='form'),
	Submount('/account', [
	Rule('/', endpoint='account_index'),
	Rule('/create/', endpoint='create_account'),
	Rule('/update/', endpoint='update_account'),
	Rule('/delete/', endpoint='delete_account'),
	Rule('/event/cancel/<string:slug>/', endpoint='event_cancel'),
	]),
	EndpointPrefix('admin_', [
	Submount('/admin', [
	resource(name='account', var='email'),
	resource(name='project', var='slug'),
	resource(name='event', var='slug'),
	resource(name='program', var='slug'),
	resource(name='application', var='slug'),
	]),
	])
	])

	from werkzeug redirect as wredirect
	from urls import url_map

	def reverse(**kwargs):
	c = url_map.bind('')
	return wredirect(c.build(**kwargs))

	...
	return reverse('form', dict(key=key, slug=slug))
	...