I was looking for a way to convert some XML data to JSON a I stumbled about https://codebeautify.org/ which did exactly what I wanted. It seems to have a lot of other toolkit which can be used for different types of conversion which a programmer can need.
I recently upgraded my Mac Desktop and I noticed a strange problem that I was not able to SSH into my desktop from my laptop. I ultimately found out that the SSH setup that came with MacOS was having some issue as when I did ssh user@localhost on the desktop I got the same error:
ssh_exchange_identification: read: Connection reset by peer
I ended up tailing the system log using the following command:
sudo tail -f /var/log/system.log
I observed the following entries in the log whenever a SSH was attempted.
com.apple.xpc.launchd[1] (com.openssh.sshd.[UUID][NUM]): Service exited with abnormal code: 1
It was clear that there was setup issue with the SSH that came with default MacOS installation. So I decided to spawn a separate SSH instance and watch it’s log:
sudo /usr/sbin/sshd -d -p 2222
This command showed up a lot of issues related to file permissions.
Permissions 0644 for '/etc/ssh/ssh_host_dsa_key' are too open.
Permissions 0644 for '/etc/ssh/ssh_host_ecdsa_key' are too open.
Permissions 0644 for '/etc/ssh/ssh_host_ed25519_key' are too open.
I fixed these permission issues by changing their permission to 400:
sudo chmod 400 /etc/ssh/ssh_host_dsa_key
sudo chmod 400 /etc/ssh/ssh_host_ecdsa_key
sudo chmod 400 /etc/ssh/ssh_host_ed25519_key
After this change the following command succeeded and I was able to do successful SSH connection to port 2222.
sudo /usr/sbin/sshd -d -p 2222
So I killed this process and decided to restart SSH:
sudo launchctl unload /System/Library/LaunchDaemons/ssh.plist
sudo lsof -i:22
echo $?
sudo launchctl load /System/Library/LaunchDaemons/ssh.plist
Once SSHD was restarted I could successfully do logins using ssh user@localhost from Desktop as well as remote login via SSH from my laptop.
Read through a DZone article which talks about a JDK released by Amazon called Amazon Corretto. This is a good news for Java community. It is a production ready JDK backed by Amazon and has been tested heavily by them. This is really an exciting development.
I love using curl command on my Mac terminal to debug my REST endpoints. However the REST call JSON output used to come in a blob of text which required further formatting in an Editor like Visual Studio Code. To allay this problem I ended up installing “jsonpp” using homebrew.
brew install jsonpp
So now I just pipe the output of my curl command to the jsonpp program and I get a fully formatted JSON.
$ curl http://localhost:8080/test | jsonpp
{
"year": 2018,
"month": 2,
"worked": 18,
"leaves": 2
}
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!
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.
I used this link to learn about conversion of java.util.Date object to JSON notation which was understandable by JavaScript and Human readable in network tab.
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.
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.
I wanted to convey / pitch an idea to somebody. To do this I used a storyboarding tool called Story Board That. This tool allowed me to create a pitch that clearly conveyed an idea. Overall a good tool!