Investigate problems due to User-Agent using Bash
Last week we had some problems with the Google Ads bot. It was not able to crawl a bunch of URLs while the browser had no problem getting through. The only difference was the User-Agent. This send us on a debugging journey through Cloudflare, gateways and micro-sites. To assist us, we’ve created a small bash script to visit an URL and show some debug info.
Trigger Lambda for large S3 Bucket with SQS
At Wehkamp we use AWS Lambda to classify images on S3. The Lambda is triggered when a new image is uploaded to the S3 bucket. Currently we have over 6.400.000 images in the bucket. Now we would like to run the Lambda for all images of the bucket. In this blog I’ll show how we did this with a Python 3.6 script.
My Little List of Tools for Prototyping
As a developer I love to prototype to see if an idea works. Thinking big and starting small is actually one of Wehkamp’s principles. And, let’s face it, that’s not easy!
Usually it starts by getting an idea of the core concept that should be validated. Especially when working with teams, communication is key. This list of tools helped me over the years to draw or code out some of these concepts and get a discussion started.
Every tool on this list is free and online.
Connect to Jira with a Private Key (OAuth) using .NET
We have a .NET service that needs to connect with Jira to create, update and read issues. It would be easy if we could use a username & password for authentication, but for this integration we need to implement the connection to Jira with a Private Key. All requests have to be signed with OAuth.
Convert JsFiddle to SVG using Node.js
I love SVG, but sometimes they are hard to create, especially when you need to visualize diagrams. HTML is way easier to program. So why not combine them? Can we use HTML to generate an SVG? And can we use JsFiddle to generate that HTML?
AWS Lambda Size: PIL+TF+Keras+Numpy?
At Wehkamp we’ve been using machine learning for a while now. We’re training models in Databricks (Spark) and Keras. This produces a Keras file that we use to make the actual predictions. Training is one thing, but getting them to production is quite another!
The main problem we’ve faced was that it was too big to actually fit into a lambda. This blogs shows how we’ve dealt with that problem.
Building a high performing last viewed list using Redis
We live in a day and age in which we can choose a data-store that matches the characteristics of our apps and (micro) services. Lately we’ve been looking into Redis as a high performing store for last viewed items. In this blog I’ll look show how to create a POC with the redis-cli and then implement it using .NET Core. We’ll be using the sorted set structure.
Fixing “white” screen Windows 10 start search
I’ve been having some problems with the search feature of Windows 10. It suddenly stopped working. I don’t exactly know when or why, but it did not come back by turning the computer on and off again. Reinstalling Cortana worked for me.
Fizz? Buzz? FizzBuzz? Let’s discuss.
What’s the buzz all about? Well, originally it started out as a small children’s game, but now and again I see it being used to detect weak developers in job interviews (I think there are better ways to do this). The assignment has a view nice properties. In this blog I would like to look at some implementations and discuss the pro’s and con’s of each implementation.