Install MongoDB database on Centos 7

MongoDB is a noSQL database and is available on Centos Linux 7. Ensure that SElinux is only on permissive.

For cases SElinux is enforcing, additional steps need to be taken which is outside of this installation note.

Step 1: Configure the repository

Create the file /etc/yum.repos.d/mongodb-org.repo

[mongodb-org-4.2]
name=MongoDB Repository
baseurl=https://repo.mongodb.org/yum/redhat/$releasever/mongodb-org/4.2/x86_64/
gpgcheck=1
enabled=1
gpgkey=https://www.mongodb.org/static/pgp/server-4.2.asc

Step 2: Install and start

sudo yum install -y mongodb-org
sudo systemctl start mongod

If all is running good, then allow it to start at boot time.

sudo systemctl enable mongod

Step 3: Verify

mongo
db.version()
exit

Further configuration can be done with the file /etc/mongod.conf

Allow database through the firewall

sudo firewall-cmd --zone=public --add-port=27017/tcp --permanent
sudo firewall-cmd --reload

Those with Selinux in mode Enforcing, allow the default mongodb port.

sudo semanage port -a -t mongod_port_t -p tcp 27017

Install Mariadb database on Centos 7

MariaDB is a replacement for Oracle Mysql Community edition.

Installation on Centos 7 is as follows;

Step 1: Install

sudo yum install mariadb-server mariadb

Step 2: Configure and assign database root password

sudo systemctl start mariadb
sudo mysql_secure_installation

sudo systemctl enable mariadb

Step 3: Verify

mysql -u root -p

Configuration of the database can be done with the files at
/etc/my.cnf
/etc/my.cnf.d/*

To allow access of the database through the firewall.

sudo firewall-cmd --permanent --add-service=mysql

Howto install PHP 7 on Centos 7

The Centos Linux 7 comes with php version 5.4.16. It is possible to install php version 7 by adding an additional rpm repository. Lets see how its done to install php 7.3 (which is the version I have chosen).

Step 1: Add Remi repository for php 7.3

sudo yum install yum-utils
sudo yum install epel-release
sudo yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpm
sudo yum-config-manager --enable remi-php73

Step 2: Install php

sudo yum install php php-common php-opcache php-mcrypt php-cli php-gd php-curl php-json php-mysql php-mbstring

Step 3: Verify 

php --version

For the web server to accept php, it needs to be restarted.

Specialised development environment will require additional php extensions. For example laravel framework could require;

opcache, bz2, calendar, ctype, curl, dom, exif, fileinfo, ftp, gd, gettext, iconv, mysqlnd, pdo, phar, posix, shmop, simpleexml, sockets, sqlite3, sysvmsg, sysvsem, sysvshm, tokenizer, xml, xmlwriter, xsl, mcrypt, mysqli, pdo_mysqli, wddx, xmlrender, zip.

and the list continues.

Android Studio 3 Installation on MS Windows 10

Android Studio is provided by Google for development of Android applications. Android Studio or AS is available for MS Windows, Linux and Mac OSX.

Following are steps to get started with a fresh MS Windows 10 machine.

Step 1. Download Android Studio

Download from https://developer.android.com/studio/index.html

and follow the installation process.

Step 2. Install Android Studio

Double click and run the downloaded EXE file. Accept the default selections and click "Next" until its installed. An internet connection is required to complete the installation.

Once installation is done, create a first application and test the emulator. In this example, I have choosen min API 23. You will be prompted by MS Windows to allow OpenJDK through firewall. Allow and proceed. Have to consider, the emulator require 1.5Gb additional disk space.

Step 3. Start and create an emulator.

In Android Studio, click "Tools" ->"AVD Manager" ->"Create Virtual Device"

Select "Phone", "Pixel 2". Click "Clone Device". This allows us to keep the original configuration intact and change what ever is required. Click Next.

Click Download for "Nougat" with API 25. Read and Accept the agreements. Click "Next" then "Finish"

First of Laravel 6 step by step tutorial

Just completed the first part of the step by step tutorial.

Feel free to check it out at https://tboxmy.blogspot.com/p/laravel-6-crud-step-by-step.html

This will complement the Laravel notes found on this blog.