This installs and setup MetaGer on a fresh debian installation.
Apache will be used as a webserver.
Redis will be used as Queue for the fetch jobs.
Supervisor will be used to keep the workers running that will fetch results from the search engines.
You can adapt those configurations to your needs.
This manual is tested on the latest stable debian version (stretch) but should also work on other distributions.

Install Dependencies

sudo apt -y update
sudo apt install -y git curl unzip build-essential libpng-dev supervisor apache2 redis-server php php-common php-curl php-mbstring php-mysql php-sqlite3 php-xml php-zip php-redis php-gd libapache2-mod-php

=> build-essential will only be needed if npm has to build some packages from source

Install the latest Composer Version

Steps from https://getcomposer.org/

php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');"
php composer-setup.php
php -r "unlink('composer-setup.php');"
sudo mv composer.phar /usr/bin/composer

Install the latest nodejs

Steps from https://github.com/nodesource/distributions/blob/master/README.md#debinstall

curl -sL https://deb.nodesource.com/setup_11.x | bash - (as root)
sudo apt install -y nodejs

Download and install dependencies of MetaGer

git clone https://gitlab.metager3.de/open-source/MetaGer.git
cd MetaGer
composer install
npm install
cp .env.example .env
Edit .env and set QUEUE_DRIVER=redis (If you need to change settings for database and redis this would be the place, too)
php artisan key:generate
Set the correct Directory Permissions (web-server should be able to write to two dirs)
- sudo chown -R :www-data storage && sudo chown -R :www-data bootstrap/cache
- sudo chmod -R g+w storage && sudo chmod -R g+w bootstrap/cache
npm run prod
cp config/sumas.xml.example config/sumas.xml (Enables some example search engines)

=> We will refer to the path where you cloned MetaGer to as $metager_path (including the MetaGer folder)

Make sure redis is running

sudo service redis restart

Setup and configure supervisor

cd /etc/supervisor/conf.d/
Create the File laravel-worker.conf and put the following content

[program:laravel-worker]
process_name=%(program_name)s_%(process_num)02d
command=php $metager_path/artisan queue:work --sleep=1 --tries=1 --timeout=295 --daemon
autostart=true
autorestart=true
user=$username
numprocs=200
redirect_stderr=true
stdout_logfile=$metager_path/storage/logs/worker.log

=> Replace the $metager_path and set the user to the username you cloned MetaGer with 3. Restart/start the supervisor daemon sudo service supervisor start or sudo service supervisor restart => If it worked correctly you will see 200 php processes with pgrep php. You can change the number in the config to whatever you find reasonable. It defines how many requests can be made to your search engines in parallel.

Setup and configure Apache

cd /etc/apache2/sites-available/
Edit 000-default.conf and put the following content

<VirtualHost *:80>
	# If you have a DNS-Entry pointing to your machine you can comment out the following line and set the dns name there
        #ServerName www.example.com 

        ServerAdmin webmaster@localhost

	# Replace $metager_path with the actual path
        DocumentRoot $metager_path/public
	<Directory $metager_path/public>
		Allow Override all
		Require all granted
	</Directory>

        ErrorLog ${APACHE_LOG_DIR}/error.log
        CustomLog ${APACHE_LOG_DIR}/access.log combined

</VirtualHost>

sudo a2enmod rewrite
restart/start the apache server sudo service apache2 restart

If you want to modify/add searchengines to your MetaGer instance you will have to modify the search engine definition in $metager_path/config/sumas.xml and you will have to add a parser class for that search engine to $metager_path/app/Models/parserSkripte/. With the information from the sumas.xml MetaGer will make a request to all search engines with type=web. The result will be given to above mentioned parser class where you have to write the code that transforms the result from the search engine API to a php object that MetaGer can use later.

Setup Metager