Showing posts with label ghostscript. Show all posts
Showing posts with label ghostscript. Show all posts

Monday, 7 March 2016

Fedora 22 Apache Tomcat and Httpd. Publishing an application in minutes.

Recalling from the previous article "Quest of the Holy Cloud" I got a provider and started a simple VM over there.
One of my first actions was to baptize my server and give it a fancy hostname.
Now lets come to the juicy part. In this article I am going to build a simple application server to handle PDF trans-code to images with a custom Java application I built.
The actions I am going to demonstrate are how to:
  • Setup OpenJKD on Fedora 22
  • Install Ghostscript libraries required for my application.
  • Download, install and configure Apache Tomcat 7
  • Install and configure Apache HTTPd.
  • Installing Open JDK

Install OpenJDK

The first step is really easy. We need a JDK or a JRE in order to run Tomcat that hosts our application. The straight option is to use opensource community JAVA: OpenJDK.
To do so, I entered the following commands:
# dnf install java
Last metadata expiration check performed 1:09:31 ago on Mon Mar  7 12:20:26 2016.
To check where java is and what has been installed:
# which java
# java -version
openjdk version "1.8.0_72"
OpenJDK Runtime Environment (build 1.8.0_72-b15)
OpenJDK 64-Bit Server VM (build 25.72-b15, mixed mode)

Install Ghostscript

Most of the software I wrote rely to Ghostscript shared libraries that are called from the corresponding Java API. To install them I entered the following commands:
# dnf install ghostscript
Last metadata expiration check performed 1:15:36 ago on Mon Mar  7 12:20:26 2016.
The library got installed at:
# ls -lh /lib64/libgs*
-rwxr-xr-x. 1 root root 16M Mar 31  2015 /lib64/

# file  /lib64/
/lib64/ ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, BuildID[sha1]=6601d742a4829cb3e4fe8197f1b1457f665ce130, stripped

Install Apache Tomcat 7

Apache Tomcat 7 can be downloaded from here as a tar.gz file by picking up a binary distribution as follows:
# cd /opt
# wget
# tar -xvf apache-tomcat-7.0.68.tar.gz

Now tomcat is not provided as a service from Fedora. To do so, we need to create a simple start script in /etc/init.d:

# cd /etc/init.d
# vi tomcat
paste the following to the script tomcat:
# start/ stop Tomcat script
# Since you are using OpneJDK put this as your java home
export JAVA_HOME
export PATH
# Where you have placed tomcat

case $1 in
exit 0
Now tomcat needs to be registered as a Linux service. To do so add those commands:
# cd /etc/init.d
# chmod 755 tomcat  
# chkconfig --add tomcat  
# chkconfig --level 234 tomcat on  
# chkconfig --list tomcat 

Installing Apache HTTPD

This comes as a standard service supported from Fedora distribution. To install it:
# dnf install httpd
For a very fast configuration of http you can edit httpd.conf and add a simple virtual host:
#  vi /etc/httpd/conf/httpd.conf
# add where "Listen 80" is:
Listen My.Host.IP.Here:80

    DocumentRoot "/www/"

    # Other directives here

Since in modern Cloud environments the linux firewall IP Tables may block everything, here are the commands to unlock the ports:
iptables -A INPUT -p tcp -m tcp --dport 80 -j ACCEPT
iptables -A INPUT -p tcp -m tcp --dport 443 -j ACCEPT
You can start the HTTP service and get its status:

# service httpd start
Redirecting to /bin/systemctl start  httpd.service
# service httpd status
Redirecting to /bin/systemctl status  httpd.service
 httpd.service - The Apache HTTP Server
   Loaded: loaded (/usr/lib/systemd/system/httpd.service; disabled; vendor preset: disabled)
   Active: active (running) since Mon 2016-03-07 14:09:27 UTC; 4s ago
 Main PID: 1760 (httpd)
   Status: "Processing requests..."
   CGroup: /system.slice/httpd.service
           ├─1760 /usr/sbin/httpd -DFOREGROUND
           ├─1761 /usr/sbin/httpd -DFOREGROUND
           ├─1762 /usr/sbin/httpd -DFOREGROUND
           ├─1763 /usr/sbin/httpd -DFOREGROUND
           ├─1764 /usr/sbin/httpd -DFOREGROUND
           └─1765 /usr/sbin/httpd -DFOREGROUND

Mar 07 14:09:27 systemd[1]: Starting The Apache HTTP Server...
Mar 07 14:09:27 systemd[1]: Started The Apache HTTP Server.
The deployment directory for tomcat where you can place your WAR files is: /opt/apache-tomcat-7.0.68/webapps/ since I have donwloaded and installed tomcat on /opt.
You can use WinSCP to copy your WAR file there:

# ls -lh  /opt/apache-tomcat-7.0.68/webapps/
total 27M
drwxr-xr-x. 14 root root 4.0K Mar  3 11:00 docs
drwxr-xr-x.  7 root root 4.0K Mar  3 11:00 examples
drwxr-xr-x.  5 root root 4.0K Mar  3 11:00 host-manager
drwxr-xr-x.  5 root root 4.0K Mar  3 11:00 manager
drwxr-xr-x.  3 root root 4.0K Mar  3 11:00 ROOT
drwxr-xr-x.  4 root root 4.0K Mar  4 16:59 zsecure-pdf
-rw-r--r--.  1 root root  27M Mar  4 16:59 zsecure-pdf.war