How to install Hackpad on a CentOS 7 VPS

In this tutorial, we will explain how to install Hackpad on a Centos 7 VPS with nginx as a reverse proxy. Hackpad is a web-based real-time wiki, based on the open source EtherPad collaborative editor. This guide should work on other Linux VPS systems as well but was tested and written for a Centos 7 VPS.

Login to your VPS via SSH

ssh root@vps

Update the system and install necessary packages

[root]$ yum -y update
[root]$ yum install git wget

Create a new system user

Create a new user for the Hackpad:

[root]$ adduser \
   --comment 'Hackpad User' \
   --home-dir /home/hackpad \
   hackpad

Install Oracle JDK 7

Hackpad requires JDK 7. Use the command below to download the latest Oracle JDK 7 from the command line using wget:

[root]$ wget --no-cookies \
    --no-check-certificate \
    --header "Cookie: oraclelicense=accept-securebackup-cookie" \
    "http://download.oracle.com/otn-pub/java/jdk/7u80-b15/jdk-7u80-linux-x64.rpm" \
    -O jdk-7u80-linux-x64.rpm

Once the rpm package is downloaded, install it with:

[root]$ yum install jdk-7u80-linux-x64.rpm

To check if JAVA has been properly installed on your CentOS box run java -version, and the output should be similar to the following:

[root]$ java -version
java version "1.7.0_80"
Java(TM) SE Runtime Environment (build 1.7.0_80-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.80-b11, mixed mode)

Install Scala

To download and install the latest scala version from the official website, run:

[root]$ wget http://downloads.typesafe.com/scala/2.11.7/scala-2.11.7.rpm

Once the rpm package is downloaded, install it with:

[root]$ yum install scala-2.11.7.rpm

Now if you run scalac -version, you should get something like this:

[root]$ scalac -version
Scala compiler version 2.11.7 -- Copyright 2002-2013, LAMP/EPFL

Install MariaDB

MariaDB 5.5 is shipped in the default CentOS 7 repository, to install it just run:

[root]$ yum install mariadb-server

To start the MariaDB service and enable it to start on boot, execute the following commands:

[root]$ systemctl start mariadb.service
[root]$ systemctl enable mariadb.service

Run the following command to secure your installation:

[root]$ mysql_secure_installation

Install Hackpad

The following commands are run as hackpad user. To switch to hackpad user run:

[root]$ sudo su - hackpad

Clone the Hackpad source code to the /home/hackpad/hackpad directory.

[hackpad]$ git clone https://github.com/dropbox/hackpad.git ~/hackpad

Edit the file ~/hackpad/bin/exports.sh as follows:

...
export SCALA_HOME="/usr/share/scala/"
export SCALA="$SCALA_HOME/bin/scala"
export SCALA_LIBRARY_JAR="$SCALA_HOME/lib/scala-library.jar"
...
export JAVA_HOME="/usr/java/jdk1.7.0_80"
export JAVA="/usr/bin/java"
...
export MYSQL_CONNECTOR_JAR="/home/hackpad/hackpad/lib/mysql-connector-java-5.1.34-bin.jar"
...

and run:

[hackpad]$ cd ~/hackpad
[hackpad]$ bin/build.sh

To create a database for our Hackpad instance, run:

[hackpad]$ contrib/scripts/setup-mysql-db.sh

And enter MySQL root password when prompted.

Copy the default settings configuration file etherpad/etc/etherpad.localdev-default.properties to etherpad/etc/etherpad.local.properties and set the etherpad.superUserEmailAddresses and topdomains, for example:

etherpad.isProduction = true
etherpad.superUserEmailAddresses = name1@example.com,name2@example.com
topdomains = yourdomainname.com,localhost

Start hackpad for the first time:

[hackpad]$ bin/run.sh

If there are no errors, you may continue with the next step.

Create a systemd service

To create a new systemd service for Hackpad, open your editor of choice as a root or sudo user and create a new file:

[root]$ vim /etc/systemd/system/hackpad.service

and add the following code lines:

[Unit]
Description=Hackpad
After=syslog.target network.target

[Service]
Type=simple
User=hackpad
Group=hackpad
ExecStart=/home/hackpad/hackpad/bin/run.sh
Restart=always

[Install]
WantedBy=multi-user.target

Start the Hackpad service and set it to start automatically on boot:

[root]$ systemctl enable hackpad.service
[root]$ systemctl start hackpad.service

To verify the unit started, run journalctl -f -u hackpad.service and you should see something like below:

[root]$ journalctl -f -u hackpad.service
Aug 22 10:42:09 vps run.sh[3080]: dropbox: 2015-08-22 10:42:09.375-0500        Starting dropbox sync
Aug 22 10:42:09 vps run.sh[3080]: dropbox: 2015-08-22 10:42:09.382-0500        Done with dropbox sync

Install and configure Nginx

Nginx is not available by default in CentOS 7 so we will use the official Nginx repository:

[root]$ wget http://nginx.org/packages/centos/7/noarch/RPMS/nginx-release-centos-7-0.el7.ngx.noarch.rpm
[root]$ yum install nginx-release-centos-7-0.el7.ngx.noarch.rpm

[root]$ yum install nginx

Next, create a new Nginx server block:

[root]$ vim /etc/nginx/sites-available/yourdomainname.com.conf

map $http_upgrade $connection_upgrade {
    default upgrade;
    ''      close;
}

server {
  server_name yourdomainname.com;

  location / {
    proxy_set_header  X-Real-IP  $remote_addr;
    proxy_set_header  X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header  Host $host;
    proxy_redirect off;
    proxy_read_timeout 300;
    proxy_pass http://localhost:9000/;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection $connection_upgrade;
  }
}

Activate the server block by restarting Nginx:

[user]$ systemctl restart nginx

That’s it. You have successfully installed your Hackpad. To access it, open http://yourdomainname.com/ in your browser. For more information about Hackpad, please refer to the official Hackpad website.