jatin-lab49

This snippet is more of an FYI rather than the usual problem plus solution. I ran into this issue recently where I was trying to build a nodejs project in Ubuntu running on Virtualbox.

In this client setup, there is a need to run certain commands/processes in the development environment in Windows, and others in Ubuntu. To help with this, I end up putting some of my code in a directory that is shared between the Windows host and the Ubuntu VM.

This setup causes an issue with symlink when running certain nodejs builds on the Ubuntu VM. Example of the error is pasted below. In this case /projects is a "Shared Folder", which is mounted from c:\develop on the Windows host.

jatin-lab49

While triaging a running docker container, I was trying to check if a jar file had the correct properties file inside it.

I found the jar file and when I ran the handy unzip command, I got this error:

service@3f50ceae48d2:/tmp$ unzip micro-service.jar 
bash: unzip: command not found

Now, usually I would just go ahead and apt-get install unzip in a Ubuntu container like this. But I was not root, so ran into another issue:

jatin-lab49

With the advances in Lambda and ECS task scheduling, I have not needed to use the trusty Quartz library for the past few years. I recently had to use it though in a project, and realized that the next job was starting when the current job was still running.

Thankfully with Spring, Quartz 2 makes this really easy. Just add the @DisallowConcurrentExecution to your job.

package com.lab49.example;

import org.quartz.DisallowConcurrentExecution;
import org.quartz.job;

jatin-lab49

We recently had a security team ask us to validate that the file being uploaded was indeed a plain text file. To do this, we decided to use Apache Tika.

The code itself is fairly straightforward:

import org.apache.tika.config.TikaConfig;
import org.apache.tika.exception.TikaException;
import org.apache.tika.io.TikaInputStream;
import org.apache.tika.mime.MediaType;
import org.apache.tika.metadata.MetaData;

jatin-lab49

Maybe this is common knowledge. For most cases whenever I needed a base64 version of an image to use in a webpage, I used one of those online sites to get it.

Recently on a client project I wasn't sure if I wanted to upload their images on an unknown site. So I did a quick Google (fine, stackoverflow) and found that we can just run this on most Linux style systems.

cat image-file.jpg | base64

Also works on macOS and for other image types