Flarum Setup Guide

Add non-root user to ensure safety in production environment:

adduser username 
usermod -aG sudo username
su - username

Update+upgrade and install Apache+MariaDB:

sudo apt-get update && sudo apt-get upgrade -y
sudo apt-get install apache2 mariadb-server -y

Add PHP PPA and install dependencies:

sudo apt-get install software-properties-common
sudo add-apt-repository ppa:ondrej/php
sudo apt-get update && sudo apt-get upgrade -y
sudo apt-get install php7.1 libapache2-mod-php7.1 php7.1-common php7.1-mbstring php7.1-xmlrpc php7.1-soap php7.1-mysql php7.1-gd php7.1-xml php7.1-cli php7.1-zip php7.1-curl wget zip unzip curl git -y

Edit PHP configuration:

sudo nano /etc/php/7.1/apache2/php.ini

And make sure the following are set to the correct value:

file_uploads = On
allow_url_fopen = On
memory_limit = 4096M
upload_max_file_size = 150M
max_execution_time = 450
date.timezone = Asia/Kolkata

Start Apache and MySQL services:

sudo systemctl start apache2
sudo systemctl start mysql
sudo systemctl enable apache2
sudo systemctl enable mysql

Then add security measures to MariaDB:

sudo mysql_secure_installation
	Enter current password for root (enter for none): Enter
	Set root password? [Y/n]: Y
	New password: 
	Re-enter new password: 
	Remove anonymous users? [Y/n]: Y
	Disallow root login remotely? [Y/n]: Y
	Remove test database and access to it? [Y/n]: Y
	Reload privilege tables now? [Y/n]: Y

Recreate root user for MariaDB so non-root users can access it too:

sudo mysql -u root -p
	DROP USER 'root'@'localhost';
	CREATE USER 'root'@'%' IDENTIFIED BY 'password';
	GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' WITH GRANT OPTION;
	FLUSH PRIVILEGES;
	EXIT;

Then create database and corresponding user for Flarum:

mysql -u root -p
	CREATE DATABASE dbname;
	GRANT ALL PRIVILEGES ON dbname.* TO 'username'@'localhost' IDENTIFIED BY 'password';
	FLUSH PRIVILEGES;
	EXIT;

After that, install composer:

cd ~
curl -sS https://getcomposer.org/installer | php
sudo mv composer.phar /usr/local/bin/composer

If it's too slow in China, use the following instead:

wget https://dl.laravel-china.org/composer.phar -O /usr/local/bin/composer
chmod a+x /usr/local/bin/composer

Give 777 perm to non-root user for Flarum install directory:

sudo chmod -R 777 /var/www/html/

cd the install directory and remove all existing files(use caution!) and install Flarum:

cd /var/www/html
sudo rm -rf *
#composer config -g repo.packagist composer https://packagist.laravel-china.org
#use repo above in China if official repo is too slow
composer create-project flarum/flarum . --stability=beta

Change owner to www-data and change perm to 755(avoid 777 in production environment)

sudo chown -R www-data:www-data /var/www/html/
sudo chmod -R 755 /var/www/html/

Edit Apache configuration:

sudo nano /etc/apache2/sites-available/000-default.conf

Add the following snippet in VirtualHost:

<Directory "/var/www/html">
AllowOverride All
</Directory>

Then save file and exit.

After that, enable rewrite for Apache and restart:

sudo a2enmod rewrite
sudo systemctl restart apache2

OPTIONALS:

Update to latest Ubuntu LTS

First make sure update-manager-core is installed

sudo apt-get install update-manager-core

Then make sure Prompt line in /etc/update-manager/release-upgrades is set to lts for LTS version or normal for non-LTS version

cat /etc/update-manager/release-upgrades

And finally start system upgrade

sudo do-release-upgrade

Create swap if you have small memory

free -m
mkdir -p /var/_swap_
cd /var/_swap_
dd if=/dev/zero of=swapfile bs=1M count=6000
#6000 means to create 6gig swap, change this number to whatever you want
mkswap swapfile
swapon swapfile
chmod 600 swapfile
echo "/var/_swap_/swapfile none swap sw 0 0" >> /etc/fstab
free -m

Enable HTTPS for your site

Clone Let's Encrypt repo and install and update the client and its dependencies

git clone https://github.com/letsencrypt/letsencrypt && cd letsencrypt
sudo ./letsencrypt-auto --help

Now ensure that port 443 is open then we can obtain our certificate by running the following

sudo ./letsencrypt-auto --apache -d your.domain.com

Then, we are gonna configure Flarum as the following

sudo nano config.php
#this should be done in Flarum root directory

And change the following line

'url' => 'http://your.domain.com'
 	to
'url' => 'https://your.domain.com'

Edit .htaccess

sudo nano .htaccess

Add the following in block

#start https redirect                                                                       
RewriteCond %{HTTPS} off                                                                      
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI}                                             
#end https redirect

Lastly restart Apache service

sudo systemctl restart apache2

Updating

The certificates last for three months (90 days in fact) so you will need to run only the following to renew it (even before it actually stops working).

sudo ./letsencrypt-auto --apache -d your.domain.com
sudo systemctl restart apache2

References

https://discuss.flarum.org/d/1623-obtain-an-ssl-certificate-and-run-your-forum-with-https-for-free

https://flarum.org/docs/installation/

https://jsthon.com/flarum-installation-guide/

https://www.howtoing.com/ubuntu-flarum

https://laravel-china.org/composer

https://askubuntu.com/questions/766334/cant-login-as-mysql-user-root-from-normal-user-account-in-ubuntu-16-04

https://wiki.ubuntu.com/BionicBeaver/ReleaseNotes