Introduction to Dynamic Web Content Dr. Charles Severance

Where are we? Database Data Model Application Software (i.e. PHP) EndUser Developer DBA Database Tools (i.e. phpMyAdmin) SQL SQL

Web Server PHP MySQL Apache Browser HTML CSS DOM JavaScrip t JQuery

HTTP - Hypertext Transfer Protocol The dominant Application Layer Protocol on the Internet Invented for the Web - to Retrieve HTML, Images, Documents etc Extended to be data in addition to documents - RSS, Web Services, etc.. Basic Concept - Make a Connection - Request a document - Retrieve the Document - Close the Connection

protocolhostdocument

Getting Data From The Server Each the user clicks on an anchor tag with an href= value to switch to a new page, the browser makes a connection to the web server and issues a “GET” request - to GET the content of the page at the specified URL The server returns the HTML document to the Browser which formats and displays the document to the user.

Browser Web Server 80

Browser Web Server 80 Click

Browser Web Server 80 Request Click GET chuck.com/page2.htm

Browser Web Server GET chuck.com/page2.htm 80 Request Click

Browser Web Server The Second Page If you like, you can switch back to the First Page. 80 RequestResponse Click GET chuck.com/page2.htm

Browser Web Server The Second Page If you like, you can switch back to the First Page. 80 RequestResponse Click Parse/ Render GET chuck.com/page2.htm

Internet Standards The standards for all of the Internet protocols (inner workings) are developed by an organization Internet Engineering Task Force (IETF) Standards are called “RFCs” - “Request for Comments” Source:

Making an HTTP request Connect to the server like a "hand shake" Request a document (or the default document) GET HTTP/1.0 GET HTTP/1.0 GET HTTP/1.0

$ telnet 80 Trying Connected to character is '^]'. GET HTTP/1.0 HTTP/ OK Date: Thu, 08 Jan :57:52 GMT Last-Modified: Sun, 19 Jan :25:43 GMT Connection: close Content-Type: text/html The First Page If you like, you can switch to the Second Page. Connection closed by foreign host. Browser Web Server

Accurate Hacking in the Movies Matrix Reloaded Bourne Ultimatum Die Hard

Getting to Know Our Browsers

Find Developer Mode Chrome: View->Developer FireFox: Safari: Preferences -> Advanced -> Show Develop Menu

Browser Web Server GET chuck.com/page2.htm The Second Page If you like, you can switch back to the First Page. 80 RequestResponse Parse/ Render Click

But there is more.... Browser – HTML, CSS, "Document Object Model" (the DOM) and JavaScript Web Server – Apache(or similar) we server with a PHP extension installed Database Server running MySQL, Postgress, Oracle, SQL Server or similar

Web ServerDatabase Server Time Apache PHP MySql Browser JavaScri pt DOMDOM php code stati c files RRC/HTTPSQL Parse Respons e Parse Reques t

Web ServerDatabase Server Time Apache PHP MySql Browser JavaScri pt DOMDOM php code stati c files Parse Respons e Parse Reques t

Our Technologies

MySQL INSERT INTO users VALUES('Smith', 'John', SELECT surname,firstname FROM users WHERE MySQL is one of the most popular free and open source database engines in the market place. MySQL powers Facebook, Yahoo!, WordPress, Drupal, Joomla, and millions of other dynamic web sites.

Apache Web Server Originally developed at National Center for Supercomputing Applications in 1994 First project / product of the Apache Foundation Brian Behlendorf founded Apache Open Source – Written in C

Science Calculations System System Scripting/ Interpreted Scripting/ Interpreted C uses curly braces { } for code blocks.

PHP <?php echo "Hello World. Today is ".date("l").". "; ?>How are you? Hello World. Today is Wednesday. How are you? PHP is the most widely used scripting language for web programming. PHP extends HTML pages by adding server-executed code segments to HTML pages. The output of the execution of the PHP code is merged into the HTML page.

The History of PHP Rasmus Lerdorf Not a trained computer scientist Consultant building dynamic web sites - got tired of doing the same thing over and over in C Reusable bits + HTML Templates

JavaScript document.write("Hello World. Today is " + Date() ); JavaScript is a C-like programming language that can be included in an HTML web page. JavaScript allows the builder of a web page to embed dynamic elements within a web page. JavaScript programs run in the browser (i.e. the Client)

JavaScript: Brendan Eich Invented JavaScript in May 1995 in ten days

JavaScript Object Notation Douglas Crockford - "Discovered" JSON Object literal notation in JavaScript

jQuery: John Resig Started jQuery in 2005 to make his web development projects easier Elegant way to select DOM elements Clean way to register events Released in 2006 Works at Khan Academy as the "Dean of Computer Science"

Acknowledgements / Contributions These slides are Copyright Charles R. Severance ( as part of and made available under a Creative Commons Attribution 4.0 License. Please maintain this last slide in all copies of the document to comply with the attribution requirements of the license. If you make a change, feel free to add your name and organization to the list of contributors on this page as you republish the materials. Initial Development: Charles Severance, University of Michigan School of Information Insert new Contributors and Translators here including names and dates Continue new Contributors and Translators here