Author Archives: cyberaka

About cyberaka

I am an experienced Senior Solution Architect with proven history of designing robust and highly available Java based solutions. I am skilled in architecting designing and developing scalable, highly available, fault tolerant and concurrent systems which can serve high volume traffic. I have hands on experience in designing RESTful MicroServices architecture using Spring Boot, Spring Cloud, MongoDB, Java 8, Redis and Kafka. I like TDD (JUnit), BDD (Cucumber) and DDD based development as required for my projects. I have used AWS primarily for cloud based deployment and I like developing cloud enabled POC as a hobby in my spare time. I have deigned and developed CI/CD pipeline using Jenkins and leveraged Docker, Kubernetes for containerizing and deploying some of my applications. I am highly experienced in creating high performing technical teams from scratch. As an ex-entrepreneur I am very much involved in the business side of the IT industry. I love interacting with clients to understand their requirements and get the job done.

Curl Command New Line Post Output

I like to use curl instead of UI tools like Postman for debugging my RESTful web services traffic whenever possible. I however didn’t like my output being messed up by the bash prompt being suffixed to the output. Something like the following:

$ curl -H "$auth_token" http://localhost:8080/xyz/abc-efg
["-","A","B","C","D","E"]$

So basically what I needed was to have a new line forced after the curl output. A quick search on internet yielded this article. So I executed the following command on my terminal.

$ echo '-w "\n"' >> ~/.curlrc

After doing this when I execute the same curl command I get the following output.

$ curl -H "$auth_token" http://localhost:8080/xyz/abc-efg
["-","A","B","C","D","E"]
$

So now the bash prompt is actually coming on a new line by default!

Validating Signature in PDF documents in Acrobat Reader

I received a digitally signed document from a trusted source. However when I proceeded to take a print it came out with “Signature Not Verified” in place of the signature field. This was not going to work so I did some googling and found out this link. It basically allowed me to validate the signature and take a printout with “Signature Valid” in place of the digital signature.

Triggering download of file using JavaScript

I recently needed to write a small piece of download code. So you pass in the ID of the document to a REST API and it should give you back a blob of the actual file. The problem however is how to actually save this blob of binary data into a local file. So a quick Googling threw up some interesting links which I finally used to finalize my solution.

Code to detect file name

Code to trigger download

Fractal Folders

I have asked myself this question a number of times. What is the best possible way to structure my UI code? Should I cluster the files using functionality or by the type of file? etc. etc.

I found a partial answer in Fractal Folders while learning ReactJS. This basically proposes that for an UI page there are many functionalities which it is comprised of and the artefacts related to these sub-functionality should be clustered as sub-folders.

 

Uninstalling and reinstalling brew

I use brew utility for all my terminal based installation needs. However recently I had to deal with a corrupted brew install. To fix this I followed this link. The uninstallation and reinstallation worked fine and I now have a working brew instance.

The commands as mentioned in the above link are:

$ cd `brew –prefix`
$ rm -rf Cellar
$ brew prune
$ rm -rf Library .git .gitignore bin/brew README.md share/man/man1/brew
$ rm -rf ~/Library/Caches/Homebrew
$ ruby -e “$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)”

 

Export JSON from RoboMongo

I use RoboMongo extensively for all my Mongo development work / debugging. I however sorely needed a way to export JSON from it. A Stack Over Flow link came up in a Google search and I was able to export JSON for my use. Basically you need to execute this command which uses “printjsononeline” function provided by Mongo to give you one line JSON for each row in the collection:

db.getCollection('collection_name').find({}).forEach(function(x){printjsononeline(x)});