Published in Sendoso Engineering

·Nov 7, 2020

Lock it carefully!

While implementing features of an app that is expected to be accessed by multiple users, we make sure to keep data consistent and not getting into a race condition, we use the locking technique. There are two types of locking, optimistic and pessimistic locking. Here, we would be talking about…

Rails

1 min read

Lock it carefully!

While implementing features of an app that is expected to be accessed by multiple users, we make sure to keep data consistent and not getting into a race condition, we use the locking technique.

There are two types of locking, optimistic and pessimistic locking. Here, we would be talking about…

Published in Sendoso Engineering

·Aug 4, 2020

Apache Kafka®. (An Overview)

Apache Kafka was originally developed at LinkedIn and was later open-sourced and is currently being managed by a company called Confluent that is a team of people that originally developed it. Apache Kafka® is a high throughput, distributed, fault-tolerant, and scalable messaging system. Too many fancy words in one sentence…

Apache Kafka

4 min read

Published in Sendoso Engineering

·Jun 22, 2020

How not to use a background job in a transaction

In modern web applications, transactions and background jobs play an important role to ensure consistency and performance. But sometimes if not used wisely and carefully can end up creating bugs that are difficult to identify in a big application. While identifying such an issue in an application where we were…

Rails

2 min read

How not to use a background job in a transaction

Apr 12, 2020

Adding a custom domain to your Heroku app

To add a custom domain to your app, you need to add your credit card information in your account but don't worry it's just to validate and no money would be charged. By default, Heroku creates a subdomain for your app so we can preview our app. Let's create an…

Heroku

3 min read

Mar 29, 2020

Substitutions in a string template

String is a primitive data type that we rely on heavily when developing applications in some way or another. Often we need to use strings with dynamic values instead of hardcoded ones. For this, we leverage string interpolation that allows us to pass dynamic values in a string. Now, if…

Ruby

2 min read

Published in Sendoso Engineering

·Aug 2, 2019

ActiveRecord::NotNullViolation when testing with RSpec

When testing Rails Model and you encounter a ActiveRecord::NotNullViolation, this means you need to provide some default value for an attribute. Normally Mysql wont bug you to provide it, but in newer versions it does require it. In my case it was due to created_at field without a default value. ActiveRecord::NotNullViolation: Mysql2::Error: Field 'created_at' doesn't have a default value This happens when Mysql turns on its strict mode by default and requires you to provide a default value for the attribute. If you don’t want to provide a value then you can just simply turn off strict mode by adding this to database.yml file:

Ruby On Rails

1 min read

ActiveRecord::NotNullViolation when testing with RSpec

When testing Rails Model and you encounter a ActiveRecord::NotNullViolation, this means you need to provide some default value for an attribute. Normally Mysql wont bug you to provide it, but in newer versions it does require it.

In my case it was due to created_at field without a default value.

ActiveRecord::NotNullViolation:Mysql2::Error: Field 'created_at' doesn't have a default value

This happens when Mysql turns on its strict mode by default and requires you to provide a default value for the attribute. If you don’t want to provide a value then you can just simply turn off strict mode by adding this to database.yml file:

test:
  host: ...
  username: ...
  strict: false

Now run your specs and they will pass without throwing this error.

Happy Coding!!

Dec 13, 2018

How I added color and git to my Ubuntu/Linux terminal

I have been using Ubuntu for about 3 years now and for all my development purposes use its Terminal. Working with different projects sometimes confuse me which branch I am using and I have to type in the command to check. …

Git

3 min read