How to encrypt a string in Java using RSA and decrypt it in Python

by Sunny Srinidhi - 1
encryption

Recently at work, I was tasked to write a Java program which would encrypt a sensitive string using the RSA encryption algorithm. The encrypted string would then be passed on to a client over public internet. The client would then use the private key to decrypt the message. But the client is written in Python. So I have to make sure the encryption and decryption wok as expected. And as always, I wrote POCs for both. And here, I'm going to document that. Creating the key pair Before we can start the encryption, we need to have a key pair. A key pair will have a public key and a private key. The public key, as the name suggests, is public. You

Fit vs. Transform in SciKit libraries for Machine Learning

by Sunny Srinidhi - 0
scikit_learn_logo

We have seen methods such as fit(), transform(), and fit_transform() in a lot of SciKit's libraries. And almost all tutorials, including the ones I've written, only tell you to just use one of these methods. The obvious question that arises here is, what do those methods mean? What do you mean by fit something and transform something? The transform() method makes some sense, it just transforms the data, but what about fit()? In this post, we'll try to understand the difference between the two. To better understand the meaning of these methods, we'll take the Imputer class as an example, because the Imputer class has these methods. But before we get started, keep in mind that fitting something like an imputer

ColumnTransformer in SciKit for LabelEncoding and OneHotEncoding in Machine Learning

by Sunny Srinidhi - 3
MachineLearning

In a very old post - Label Encoder vs. One Hot Encoder in Machine Learning - I had demonstrated how to use label encoding and one hot encoding to separate out categorical text data into numbers and different columns. But the SciKit library has come a long way since I wrote that post, and it has made life a lot more easier. The developers of the library might have realised that people use LabelEncoding and OneHotEncoding very frequently. So they decided to come up with a new library called the ColumnTransformer, which will basically combine LabelEncoding and OneHotEncoding into just one line of code. And the result is exactly the same. In this post, we'll quickly take a look at

SpaceX shares video of successful parachute tests of the Crew Dragon spacecraft

by Sunny Srinidhi - 0

SpaceX today shared of video on Twitter of it testing the parachutes for the Crew Dragon spacecraft. And this test was the 13th successful test of the parachutes, in a row. SpaceX only had a target of 10 successful tests by the year end, as Elon Musk had stated in a joint press conference with NASA last month at SpaceX headquarters in Hawthorne, California. So its a new achievement. https://twitter.com/SpaceX/status/1191067348914098176?s=20 In this latest test video, the company intentionally did not deploy one of four parachutes, just to demonstrate that it is safe even it of them fails to deploy. This is a rare occasion for SpaceX, because this time they are actually ahead of the schedule that Elon Musk had set

Invoke an AWS Lambda Function from another Lambda Function

by Sunny Srinidhi - 0

I recently discovered that you can't invoke more than one Lambda function in AWS for an S3 event, with the same prefix and suffix (or just with the same suffix, which was the issue in my case). So I wanted a way to invoke one Lambda function from another Lambda function. If you're feeling kind of lost, check out the problem statement in my Github project. That could possibly add some context to the problem. If you don't want to go there, I'll try to explain it here again. The Problem and the Requirement In one of our projects, we have a Lambda function which is invoked whenever a text file is uploaded to a particular S3 bucket. The Lambda function takes

Bixby Routines, they actually work!

by Sunny Srinidhi - 0
Bixby Routines

If you, for some reason have been living under a rock and don't know what Bixby is, it's the virtual assistant that Samsung has been trying to shove down your throat for a while now. But fortunately, with their latest smartphones, the Galaxy Note 10 series, they've given the option to silence Bixby forever, with the "Side Key" option. Today, we're not going to talk about how horrible or awesome the virtual assistant is, rather, how some features of Bixby are actually very useful, and work as expected. We're going to talk about Bixby Routines. On my Galaxy Note 9, I was using a third party app to map the Bixby key to open up the Google app, and had mapped

How to automatically trigger AWS Lambda functions using CloudWatch

by Sunny Srinidhi - 0

If you have AWS Lambda functions which need to be triggered periodically, like CRON jobs, there are many ways to achieve this. But I recently discovered a very easy and AWS-way of doing this, which makes life a lot easier. So, there are a lot of ways you can trigger Lambda functions periodically. One of the most common ways I've see people doing this is adding an API Gateway to the Lambda function, and then calling that API periodically as a CRON job from one of the machines in the setup. I actually thought this is how you're supposed do to that. Okay, let me make this clear. I'm not a DevOps guy. I just learn these things as and when

Apache Kafka Streams and Tables, the stream-table duality

by Sunny Srinidhi - 0
apache_kafka_streams

In the previous post, we tried to understand the basics of Apache's Kafka Streams. In this post, we'll build on that knowledge and see how Kafka Streams can be used both as streams and tables. Stream processing has become very common in most modern applications today. You'll have a minimum of one stream coming into your system to be processed. And depending on your application, it'll mostly be stateless. But that's not the case with all applications. We'll have some sort of data enrichment going on in between streams. Suppose you have one stream of user activity coming in. You'll ideally have a user ID attached to each fact in that stream. But down the pipeline, user ID is

Getting started with Apache Kafka Streams

by Sunny Srinidhi - 1
apache_kafka_streams

In the age of big data and data science, stream processing is very significant. So it's not at all surprising that every major organisation has at least one stream processing service. Apache has a few too, but today we're going to look at Apache's Kafka Streams. Kafka is a very popular pub-sub service. And if you've worked with Kafka before, Kafka Streams is going to be very easy to understand. And if you haven't got any idea of Kafka, you don't have to worry, because most of the underlying technology has been abstracted in Kafka Streams so that you don't have to deal with consumers, producers, partitions, offsets, and the such. In this post, we'll look that a few concepts of

Put data to Amazon Kinesis Firehose delivery stream using Spring Boot

by Sunny Srinidhi - 1
Amazon Kinesis Firehose

If you work with streams of big data which have to be collected, transformed, and analysed, you for sure would have heard of Amazon Kinesis Firehose. It is an AWS service used to load streams of data to data lakes or analytical tools, along with compressing, transforming, or encrypting the data. You can use Firehose to load streaming data to something like S3, or RedShift. From there, you can use a SQL query engine such as Amazon Athena to query this data. You can even connect this data to your BI tool and get real time analytics of the data. This could be very useful in applications where real time analysis of data is necessary. In this post, we'll see

Top