CS 382 DATABASE-DRIVEN WEBSITES Instructor: Dr. Xenia Mountrouidou CS382 1

Who am I?  Dr. X  PhD at North Carolina State University  Worked for IBM  Post doc at College of William and Mary  Scuba diver, manga comics collector, science fiction reader. CS382 2

Course Objectives  At the end of this class you will be able to:  Design and implement a professional database-driven website  Develop interactive websites with PHP and Ruby on Rails  Design and interface with a MySQL database through PHP and Ruby on Rails  Understand the performance and security issues with database-drive websites CS382 2

Why did you take CS 382? CS382 4

Why do you need CS 382?  The majority of professional webpages use a database… or multiple databases  Examples?  Software development:  Middleware  Web development  Cloud computing CS382 4

Lectures  Check the schedule in the class webpagewebpage  All slides are posted but may be revised accordingly  Read the syllabus and policies carefully  Reading and labs will be posted online  You will need to prepare for hands on class exercises CS382 6

Lectures  Lectures will be interactive. This means:  You will need to study the new material before every lecture (slides, book, and online material)  We will have a lab on every lecture… which means coding CS382 6

How to get help  Join my office hours: M/W/F 9:00-10:30 am at Merritt Penticoff 203  Or set an appointment with me via  Use the recommended textbooks (on Blackboard, Documents):  PHP and MySQL Web Development, 4th Edition (Developer's Library Series), by Luke Welling, Laura Thomson  Agile Web Development with Rails, by Sam Ruby CS382 7

Office hours and help-My schedule CS382 9 Color code: green – available, purple – in class, black – available by appointment only, red – please do not disturb

Grading Labs10% Project40% Homework30% Final exam20% Total100% CS382 8  Homework and Programming projects will be posted online on the class webpage

How to be successful in this class  Complete all homework assignments  On time!  Practice with coding:  Codeacademy:  W3Schools:  Codeschool: redux redux CS382 11

How to be successful in this class  If you like tutorials: CODE!! Don’t just read  Good PHP tutorials eginners/ eginners/  Good Ruby tutorials:  Good Rails tutorials: CS382 12

How to be successful in this class  Dedicate time, work smarter not harder:  Ask immediate feedback  Do not just read, try to explain what you read… to your grandma!  Check the StudyHacks blog:  linear-algebra-in-10-days-astounding-experiments-in- ultra-learning/#more linear-algebra-in-10-days-astounding-experiments-in- ultra-learning/#more-2537 CS382 13

Programming Project  You can start working on this from the first week of the class  Design and implementation of a professional website with a database:  Professional Style  Interactive  I will post some topics  You may complete the project in teams of two CS382 9

Programming Project  Your project should have the following features: 1. Use a Server-Side Framework – PHP or Ruby 2. Database – use MySQL database (you may have to create it)  You may use a template for the page appearance or design your own    CS382 9

Programming Projects 1. Outreach website with database 2. Entertainment website with database: Movies Songs Art from JU (performances, works of art) 3. E-commerce website Pet store Book store 4. Blog Microblogging Technology blog 5. More project ideas: CS382 9

Homework  It will involve:  Applying what we learned in class  Clean design and coding  Clear documentation (README files)  Homework will be completed individually CS382 17

Policies  Cheating means “submitting, without proper attribution, any computer code that is directly traceable to the computer code written by another person.”  Or even better:  “Any form of cheating, including concealed notes during exams, copying or allowing others to copy from an exam, students substituting for one another in exams, submission of another person’s work for evaluation, preparing work for another person’s submission, unauthorized collaboration on an assignment, submission of the same or substantially similar work for two courses without the permission of the professors. Plagiarism is a form of Academic Misconduct that involves taking either direct quotes or slightly altered, paraphrased material from a source without proper citations and thereby failing to credit the original author. Cutting and pasting from any source including the Internet, as well as purchasing papers, are forms of plagiarism.”  Students earn F for any homework assignment that they have cheated.  A second cheating attempt will be escalated to the chair of the Division with consequences on the student’s graduation. CS382 18

Policies  You may discuss homework problems with classmates, after you have made a serious effort in trying the homework on your own.  You can use ideas from the literature (with proper citation).  You can use anything from the textbooks/notes.  The code you submit must be written completely by you. CS382 19

Policies  Read the collaboration policy carefully.  Late policy:  2% is reduced by every day the homework is late CS382 20

Principles of Pair Programming CS382 10

Principles of Pair Programming  All I Really Need to Know about pair programming I Learned in Kindergarten  Share everything.  Play fair.  Don’t hit people.  Put things back where you found them.  Clean up your own mess.  Don’t take things that aren’t yours.  Say you’re sorry when you hurt somebody. CS382 12

Principles of Pair Programming  Wash your hands before you eat.  Flush.  Warm cookies and cold milk are good for you.  Live a balanced life – learn some and think some and draw and paint and sing and  Dance and play and work every day some.  Take a nap every afternoon.  When you go out into the world, watch out for traffic, hold hands and stick together.  Be aware of wonder. CS382 13

Professional Portfolio  A collection of projects you implemented for a class or for fun.  Examples:    programming-portfolio.php programming-portfolio.php  ming.html ming.html CS382 24

The INTERNET… and a bit of history 15 CS382

What is the internet?  A “series of tubes”  How many Internets are out there?  Is Google one of them? CS382 26

What is the internet?  A collection of computer networks that use a protocol to exchange data  Is the World Wide Web (WWW) and the internet the same? CS382 27

Key aspects of the internet  Sub-networks are independent  Computers can dynamically join and leave the network  Built on open standards  Lack of centralized control (mostly)  Everyone can use it with simple, commonly available software CS382 28

People and organizations  Internet Engineering Task Force (IETF): internet protocol standards  Internet Corporation for Assigned Names and Numbers (ICANN): decides top-level domain names  World Wide Web Consortium (W3C): web standards CS382 29

CS Layered architecture

Internet Protocol (IP)  Simple protocol for data exchange between computers  IP Addresses:  32-bit for IPv5  128-bit for IPv6 CS382 31

Transmission Control Protocol (TCP)  Adds multiplexing, guaranteed message delivery on top of IP  Multiplexing: multiple programs using the same IP address  Port: a number given to each program or service  port 80: web browser (port 443 for secure browsing)  port 25:  port 22: ssh  Some programs (games, streaming media programs) use simpler UDP protocol instead of TCP CS382 32

Web Servers  Web server: software that listens for web page requests  Apache  Microsoft Internet Information Server (IIS) CS382 33

Application Server  Software framework that provides an environment where applications can run  Apache  Glassfish  WebSphere  WebLogic CS382 34

Web Browser  Web browser: fetches/displays documents from web servers  Mozilla Firefox  Microsoft Internet Explorer (IE)  Apple Safari  Google Chrome  Opera CS382 35

Domain Name Server (DNS)  Set of servers that map written names to IP addresses  Example: ju.edu →  Many systems maintain a local cache called a hosts file  Windows: C:\Windows\system32\drivers\etc\hosts  Mac: /private/etc/hosts  Linux: /etc/hosts CS382 36

Uniform Resource Locator (URL)  Identifier for the location of a document on a web site  Example:  Upon entering this URL into the browser, it would:  ask the DNS server for the IP address of dept.ju.edu  connect to that IP address at port 80  ask the server to GET /cs/index.html  display the resulting page on the screen CS382 37

Hypertext Transport Protocol (HTTP)  Set of commands understood by a web server and sent from a browser  Some HTTP commands (your browser sends these internally):  GET filename : download  POST filename : send a web form response  PUT filename : upload  Exercise: simulate a browser with a terminal window CS382 38

HTTP Error Codes  When something goes wrong, the web server returns a special "error code" number  Common error codes: CS NumberMeaning 200OK page has moved (permanently or temporarily) 403 you are forbidden to access this page 404page not found 500internal server error

Web Languages  Hypertext Markup Language (HTML): used for writing web pages  Cascading Style Sheets (CSS): stylistic info for web pages  PHP Hypertext Processor (PHP): dynamically create pages on a web server  JavaScript: interactive and programmable web pages CS382 40

Web Languages(cont.)  Asynchronous JavaScript and XML (Ajax): accessing data for web applications  eXtensible Markup Language (XML): metalanguage for organizing data  Ruby on Rails CS382 41

DATABASE DRIVEN WEBSITES CS382 42

What is a database driven website?  Information changes often! CS382 43

Examples? CS382 44

Technologies  PHP  JSP  ASP  PERL  Cold Fusion  Ruby  Python CS382 45

Client vs server programming CS382 46