Tutorials Index Page 7

How to Show or Hide Files in Finder (OSX)

If you want to show or hide files in finder you can use defaults command. To enable it use defaults write com.apple.finder AppleShowAllFiles TRUE. You need to kill Finder, check here for more details


Test SSL / TLS with GnuTLS from the Command Line

In this tutorial we are going to use gnutls-cli from the command line to test SSL/TLS connection. This command could be useful to test a web or an imap server. Install it with: sudo apt -y install gnutls-bin. Example of usage: gnutls-cli -d 5 imap.gmail.com -p 993


Javascript: How to remove a specific element from an array?

In this small tutorial we will give example on how to remove a specific element from an array with javascript. Code example: var index = array.indexOf(5); if (index > -1) { array.splice(index, 1); }


How to Prepare for the Project Management Professional (PMP) Exam Questions

The Project Management Professional (PMP) is the most important industry-recognized certification. We recommend Rita Mulcahy's book, Andy Crow study PMP guides and Kin Heldmen study guide. We also provide links to free PMP questions. Finally remember the PMBok is your bible! Read here for more details.


How to get selected value of dropdown in javascript (with jQuery example)

We will explain hot to retrieve the selected element using javascript. e.options[e.selectedIndex].value will return the value of the selected element where e is the variable obtained with document.getElementById("selector"). Check here a full jQuery example also. Read our tutorial for more details.


Backup mongodb with crontab

In this tutorial we are going to explain how to do daily backups of mongodb using cron.


Install go in raspberrypi steps

Follow this steps to install go on the raspberry pi. We don't use apt to install go and instead we download the latest version from https://golang.org.


Mongoengine: How to use filefield for storing images and files

Check here an example on how to use mongoengine filefield. Mongoengine FieldField uses GridFS to store the files, check here how to use it in your project.


Javascript http request: No 'Access-Control-Allow-Origin' header is present on the requested resource error

When you try to fetch data from a different domain using javascript you will get the error: No 'Access-Control-Allow-Origin' header is present on the requested resource. This is a security feature of web browsers. The proper solution is to use CORS, check here for full solution. Alterntive you can code a custom proxy or use JSONP.


How to check internet speed on a Linux server from the terminal using cli?

We explain how to use speedtest python project to check internet speed via the terminal. We will also explain how to save historical network speed on your linux server with a very cron line. Finally we explain how to plot the generated csv data.