Khebbies blog

If humans do stuff that computers can do, computers gather at night and laugh at the human

Sometimes we have to do really boring work as software developers. For instance today we are working on moving a domain from our internal DNS servers to AWS route53. This domain has been in our hands for 25 years - we have a lot of DNS records. We naturally have

How should I do error handling?

In my last post I told you not to do generic error handling. The natural next question is then "How should I do error handling?". That question can be hard to answer, and as always in software development the answer is: "It depends". First of all error handling in every

architecture

Don't do generic error handling

So I just had a look at a fairly new restful api, written in kotlin. The developers who made the api decided to be smart about error handling - instead of doing error handling in every api endpoint - why not just do some generic error handling. The error handling

Are you smart enough to debug your code?

Everyone knows that debugging is twice as hard as writing a program in the first place. So if you're as clever as you can be when you write it, how will you ever debug it? Brian Kernighan from The Elements of Programming Style, 2nd edition, chapter 2 “Simple doesn’t

One of the best programming skills you can have is knowing when to walk away for awhile.

"One of the best programming skills you can have is knowing when to walk away for awhile." - Oscar Godson "Sometimes it's better to leave something alone, to pause, and that's very true of programming." - Joyce Wheeler "Best ergonomics advice is 'stay hydrated'" Michael Feathers When working in a

We value code that is easy to maintain over code that is easy to write

"We value code that is easy to maintain over code that is easy to write" from Growing object-oriented software guided by tests. "Quick becomes quicksand" Uncle Bob. This is the first post in the Series on wise software catchphrases This is probably one of the most overarching catchphrases in this

Featured

Series on wise software catchphrases

So I follow Code Wisdom on twitter: https://twitter.com/CodeWisdom What the account basically does is tweet quotations by famous and not so famous software developers. The quotes are wisdom gathered through many years of working with software development. In my day to day job, I work with quite

Serverless Monitoring heat remotely

So I attend a small church and I am responsible for the heating system. That should be a simple task, but sometimes people fiddle with the heating system and sometimes the furnace simply stops. And even though I live pretty close to the church I don't want to go there

Docker vs binary packages

The other day I had a conversation with a Operations Engineer who made a bold statement: "Sending us a docker container is not different from sending us a .deb package" I do not agree with that statement at all but didn't have the time to counter it, so instead I

Exception handling for junior devs

Exception handling is a very important thing for creating production ready code. When you are a brand new developer you might not know how to do exception handling properly. Here I will try to describe a few basic rules that should be followed when coding. Please note that as always

TILs (Today I Learneds)

I have started a TIL [https://khebbie.github.io/]. To be quite honest, I don't post a lot on this blog, but on my TIL, I do post a lot more often.

Values in software development

During my job as a software developer I have stumbled upon some values that makes a lot of sense to me: We value code that is easy to maintain over code that is easy to write I am not sure if this is the origin of this value, but I

Vlog: what is an API (for non-tech people)

So I decided to try something new: I made a video explaining what an API is! Of course if you are a software developer you probably already know, so move on then, or wait just a second - you could show this video to a business person you know :-)

ecto

Mix tasks in Phoenix using Ecto

Working with Phoenix [https://github.com/phoenixframework/phoenix] version 0.16 I needed to import some records from a csv file. My first problem was where to place the tasks, after some research I found that you place them under lib/tasks and name them some_name.ex (not exs)

Optimistic locking in mongomapper and eventbus

In Be My Eyes we use mongomapper [https://github.com/mongomapper/mongomapper/] and eventbus [https://github.com/kevinrutherford/event_bus], both are very good tools that make my everyday life as a developer easier - except when it doesn't. We had a problem where more than one helper is added

resque

Setup resque mailer on Ubuntu 14.04

I recently moved a site from EngineYard to Digital Ocean. The site used resque mailer to send emails. So I had to set up resque to handle the queue. I decided to start it with upstart and added the following script to /etc/init/resque.conf description "Resque worker configuration"

So you think the internet is a dark and hostile place...

Well think again! Last night we had a big breakdown on bemyeyes.org. Some famous actor mentioned us on facebook - which is by the way great, and well the database could not handle it. Within 6 minutes the database went from responding within about 3-600 ms to 6-8000 ms.

Working from home

So yesterday we did the big launch of Be My Eyes [http://www.bemyeyes.org/], and what a splash we made! I am so proud of having been part of this. I work from home, which basically means that I have set up an office in the bedroom. Working from

mongo

Map Reduce in MongoDb

I had a problem where I needed to aggregate some documents in MongoDb. In Be My Eyes, we keep records of which version of ios the app is installed on. We do this to know which versions to support. The natural solution would be to use the aggregation framework, however

mongo

Unix commandline

Just a few scripts useful for changing many files at once. To replace all double quoted strings with single quoted strings in ruby to make rubocop happy: find . -type f -iname '*.rb' -exec sed -i.bak "s/\"/'/" "{}" +; Now find all the places where you do string interpolation and

ruby

EventBus in a Sinatra app

I had a sinatra app (the Be My Eyes app), that I thought had a bit too much code in the route file. So I investigated how to make that better. What I came up with was that it would be great to have some kind of EventBus, where I

Frontend developers and their tools

I read some frontend developer magazines like net magazine and Web Designer Magazine. Now I really like both of them, and so I thought about how great it would be to have something like that for backend developers (or maybe full stack developers). And I thought about why it is

commandline

Git bisect

Oh how I love git bisect In the last couple of weeks I had some bugs that were introduced at a unknown commit. Actually I couldn't even find out what code was working wrong. I did however know excactly what was wrong in the UI. For problems like this git

mac

My Mac Setup

This is just a run through of my Mac setup - I do this mostly for myself, so I can find it whenever I need to setup a Mac, but you are welcome to take a peek :-) First of all Caps Lock (I never hit Caps Lock except by

mongo

Update all records in mongodb

Recently we discovered a problem in Be My Eyes where an id was not unique. So we needed a quick fix to make all ids a forthrunning unique number before solving the problem in the code. On stackoverflow i found this question: http://stackoverflow.com/questions/4146452/mongodb-what-is-the-fastest-way-to-update-all-records-in-a-collection And I