Class based Celery task

In the previous post, I showed you how to implement basic Celery task that make use of @task decorator and some pattern on how to remove circular dependencies when calling the task from Flask view. Let's recall some part of the code. def run_task_async(): task = chain(long_run_…

Celery integration with Flask

As of Celery version 3.0 and above, Celery integration with Flask should no longer need to depend on third party extension. That's what they said. However, my experience integrating Celery with Flask especially when using Flask with blueprints shows that it can be a little bit tricky. Challenges So…

Change IP address for existing nodes in CDH 5.3

Today I discovered way to handle changes of IP address for Hadoop cluster managed by CDH 5.3. I think this should also be applicable for CDH 5.x. Took me couple of hours to figure this one out :/ I've done this previously but it was on CDH 4.x.…

Creating Brew external command

Recently I had the need to create a homebrew external command to extend homebrew default behavior. My goal is to extend brew deps command by creating a new command brew deps-group. Executing the command will list all top-level packages in homebrew that is related to each other by common dependencies,…

Kaggle: Bike Sharing Demand Part 1

Finally had a chance to play around with Kaggle challenge, and bike sharing demand seems to be the easiest to tackle - no domain expertise required or atleast very minimal. This is going to be Part 1 where I'll go over how I apply minimal statistical knowledge to extract features.…

Image filtering with convolution matrix

I was reading reading about convolution matrix which was brillianty explained by Colah. If you're looking for good blog to follow, you might want to add him into the list. One of the application of convolution matrix is image manipulation like applying filters to the image. The cool part is…

Face-tracking with OpenCV

I've been toying with OpenCV lately and surprisingly it is pretty easy to implement face-tracking using OpenCV. However, OpenCV documentation is a bit lacking especially with its Python binding. Installing OpenCV In OSX (yes, I've moved to OSX from Windows since I do a lot of *nix development now), this…

Moving to Ghost

Haven't post anything for the past couple of months. I just started moving all the contents to Ghost blogging platform. Previously, I was hosting my blog on Github pages, which means I have to use some sort of static generator and push the content to Github pages. I was using…