Dynamic Web Programming

Dynamic Web Programming: Application and Transfer

Active Server Pages (ASP)When a browser calls an ASP document, the ASP Server reads the .asp document andSubstitutes appropriate files for the (server-side) include statementsRuns the ASP code (Visual Basic Script – see the Tutorial and Language Reference, …)Returns the resulting HTML code to the browserExample (code, copy of database)

ASP Key Points (1)ASP code enclosed in: <% VBScript code %>Everything outside is HTMLThe result of the combined HTML and ASP code must be a “standard” HTML document, e.g.:<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Final//EN"><html><head><title>Miracle Drug Study</title><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"><meta name="Description" content=""><meta name="Keywords" content=""><link rel=STYLESHEET type="text/css" href=""></head><body></body></html>

ASP Key Points (2)Connect with database:Create connection object:set conn = Server.CreateObject("ADODB.Connection")Open connection:conn.open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=f:\web\database\rescomp\study.mdb")Submit a (read-only) Query:Generate SQL statement:SQL = "SELECT FirstName, LastName, DOB, Gender FROM Patients WHERE Gender = '" & Gender & "' ORDER BY FirstName DESC"set Patients = conn.execute(SQL)

ASP Key Points (3)Move through the data records:do while NOT Patients.eof Name = Patients(0) & " " & Patients(1) Patients.MoveNextloopAdd to or edit table:Create and open Record Set object:set RS = Server.CreateObject("ADODB.Recordset")RS.Open “table name", conn, , adLockOptimistic, adCmdTable(where adLockOptimistic = 3, adCmdTable = 2)

ASP Key Points (4)Add to or edit table (continued):Create new record, Edit, & Update:RS.AddNewRS(“Dosage”) = 200RS.UpdateOr Find desired record, Edit, & Update :do while NOT RS.eof if RS(“ID”) = 7 then RS(“Dosage”) = 200 RS.Update else RS.MoveNext end ifloop

ASP Key Points (5)Clean up (free server resources) when done:Queries:Patients.Closeset Patients = nothingRecord Sets:RS.Closeset RS = nothingThe Connection:conn.closeset conn = nothing

ASP SecurityApart from various Internet Information Services (IIS – Window’s Web service) security holes (for viruses and worms), security is quite good.Use https:// if you want to protect content over the internet – provides Secure Socket Layer (SSL) security

ASP ResourcesASP IntroductionMicrosoft’s VBScript Tutorial & Language Reference (also here)WebMonkey’s tutorial

ColdFusionEasy-to-learn Server-Side Scripting Language: CFML, or Cold Fusion Markup Language, is embedded in HTML codeCF code is enclosed in or by CF tags: <CFtagnameCF code ><Cftagname > CF Code </Cftagname >Documents must end in .cfmColdFusion is Case InsensitiveExample (code, copy of database)

ColdFusion Key Points (1)All #variables# are enclosed in # signsHTML output which includes of CF variables must be surrounded by CF output tags; e.g.:<Cfset height = “tall”><CFoutput>The <B>#height#</B> boy fell.<Cfoutput>

ColdFusion Key Points (1)Connect with database and run query simultaneously:<CFQUERY Name="Patients" dbtype="dynamic" connectstring="#DBdriver# #DBfile#">SELECT ID, FirstName, LastName FROM PatientsORDER BY FirstName</CFQUERY> Where the variables are defined beforehand:<CFset Dbdriver = "Driver={MICROSOFT ACCESS DRIVER (*.mdb)}; UID=admin; PWD=; dbq="><CFset Dbfile = "f:\web\database\rescomp\study.mdb">

ColdFusion Key Points (2)Access Query Results<SELECT name="PatientID"><CFoutput QUERY="Patients"> <OPTION value=#ID#>#FirstName# #LastName#</CFoutput></SELECT>Insert Data from a FormIf a HTML form submits variables to be inserted, do so directly using CFinsert:<CFinsert tablename="Treatment" dbtype="dynamic" connectstring="#DBdriver# #DBfile#"> All variables in the form object (e.g. Form.var1) that match attributes in the table are inserted into the table automatically

ColdFusion Key Points (3)Insert Data using Cfquery (SQL):<CFquery name="Treatment" dbtype="dynamic" connectstring="#DBdriver# #DBfile#">INSERT into TreatmentVALUES (#PatientID#, #EventID#, Now(), #Dosage(mg)#, #Severity#, #Time#)</CFquery>Other Data editing features also available; see documentation

Cold Fusion ResourcesCold Fusion IntroductionAllaire/Macromedia’s Documentation Web page Developing CF ApplicationsCFML ReferenceCFML Quick ReferenceWebMonkey’s tutorialSecurity links page

Practical Extraction andReport Language (Perl)UbiquitousOriginally designed to be a better general purpose tool than a Unix shell, it has grown and spread to be supported from Windows to Macintosh to VMS.Powerful but CrypticExample (code)

Perl Key Points (1)The file itself must end in “.cgi” or “.pl”First linemust specify the location of the Perl engine (The DBI module will not work for “#!/usr/local/bin /perl[5]” – see below):#!/uva/bin/perl -wFirst printed line must be the following if you want its response to go to a browser:print "Content-type: text/html\n\n";

Perl Key Points (3)Set the usual parameters:my $hostname = “lebec.tc.edu"; my $username = “gordie"; # "my" defines a local variablemy $password = “mine122";my $database = $username . "_study"; # = dld5s_studymy $data_source = "DBI:mysql:$database:$hostname";Connect to the database:my $dbh = DBI->connect($data_source, $username, $password)or die "Can't connect to $data_source: $DBI::errstr\n";

Perl Key Points (4)Define the SQL statement and executemy $SQL = "SELECT FirstName, LastName, DOB, Gender FROM Patients WHERE Gender = '$Gender‘ ORDER BY FirstName DESC";my $sth = $dbh->prepare($SQL)or die "Unable to prepare $SQL: dbh->errstr\n";$sth->execute or die "Unable to execute query: $dbh->errstr\n";Clean up$sth->finish;$dbh->disconnect;

Perl ResourcesPerl Programming IntroductionPerl Programming for the WebPerl DocumentationOverview, Built-in functions, Data types, Regular expressions, …Modules: DBI(1), DBI(2), CGIWebMonkey’s Tutorial, etc.MySQL and PERL for the Web by DuBois (New Riders)Learning Perl by Schwartz & Christiansen (O’Reilly)Programming Perl by Wall, Orwant, & Christiansen (O’Reilly)Programming the Perl DBI: Database Programming with Perl by Descartes, Bunce, & Mui (Editor) (O’Reilly)

PHPExampleAdd SourceIndex Source

PHP: Hypertext Preprocessor (PHP)HTML embedding scripting language (see the PHP online manualWhen a browser calls a PHP document, the Server reads the PHP document andRuns the PHP codeReturns the resulting HTML code to the browserExample (code)

PHP Key Points (1)Filename must end in .php or .phtmlPHP code enclosed in <?php PHP code ?> or <? PHP code ?>Everything outside is HTMLOutput is (generally) to a browser requiring standard HTML

PHP Key Points (2)Connecting with RDBMS and editing, adding, and deleting databases therein are all done through PHP functionsConnect with MySQL RDBMSmysql_connect($hostName, $userName, $password) or die("Unable to connect to host $hostName");Connect with databasemysql_select_db($dbName) or die("Unable to select database $dbName");

PHP Key Points (3)Queries: Nearly all table interaction and management is done through queries:Basic information searches$SQL = "SELECT FirstName, LastName, DOB, Gender FROM Patients WHERE Gender = '$Gender‘ ORDER BY FirstName DESC";$Patients = mysql_query($SQL);Editing, adding, and deleting records and tables$SQL = "INSERT INTO Patients (FirstName, LastName) VALUES('$firstName', '$lastName')";$Patients = mysql_query($SQL);

PHP Key Points (4)Cleaning up: close the database connectionmysql_close();

PHP/MySQL SecurityThe same problems as PHP occur with Perl if you run it as a Perl or CGI script. See the passwords link

PHP ResourcesPHP and MySQLPHP DocumentationPHP’s TutorialWebMonkey’s TutorialPHP and MySQL Web Development by Welling & Thomson (SAMS)Beginning PHP4 by Blan, Choi, et. al (Wrox)

(Other) BooksMySQL by DuBois (New Riders)MySQL and PERL for the Web by DuBois (New Riders)MySQL & mSQL byYarger, Reese, & KingPHP and MySQL Web Development by Welling & Thomson (SAMS)Beginning PHP4 by Blan, Choi, et. al (Wrox)Learning Perl by Schwartz & Christiansen (O’Reilly)Programming Perl by Wall, Orwant, & Christiansen (O’Reilly)Programming the Perl DBI: Database Programming with Perl by Descartes, Bunce, & Mui (Editor) (O’Reilly)SQL-99 Complete, Really by Gulutzan & Pelzer (R&D Books)

PHPPHP is a widely-used general-purpose scripting language that is especially suited for Web development and can be embedded into HTML.PHP is a project of the Apache Software Foundation. PHP stands for PHP: Hypertext Preprocessor.

Let’s get started.As we already said PHP can be embedded into HTML:#!/usr/local/bin/php<html><body><?php echo “Hello I am a PHP script”;?></body></html>

First fileSave the file with a PHP extension in your public_html folder.Give the webserver execute permission (chmod 755 hello.php is the easiest way to do this)Point a webserver at the fileLet’s look at the first line of the file#!/usr/local/bin/php

Something more Useful<?php echo $_SERVER["REMOTE_ADDR”]; ?>What is echo(); ? echo() is a PHP function which prints output to the webpage, php has many functions that do this, print(), printf() are two examples.What is $_SERVER?!$_SERVER is a special reserved PHP variable that contains all web server information. It's known as an Autoglobal (or Superglobal).

Mixin and matchin PHP & HTML<?php if (strstr($_SERVER["HTTP_USER_AGENT"], "MSIE")) {?><h3>strstr must have returned true</h3><center><b>You are using InternetExplorer</b></center> <?php } else { ?> <h3>strstr must have returned false</h3> <center><b>You are not using Internet Explorer</b></center> <?php } ?>Here we see you can mix and match HTML and PHP together, this is because PHP does the PHP bit first, it’s output is HTML and then bangs all the HTML together.

PHP FormsForms are a useful part of any internet site, and I’m sure you’ve used them in the past. Forms are part of HTML, however you can pass their values to a PHP script. Here is a simple HTML form which you can put in any HTML file:<form action="action.php" method="POST"> Your name: <input type="text" name="name">Your age: <input type="text" name="age"> <input type="submit"> </form>This isn’t specific to PHP, the only thing to notice is how we pass the values to “action.php”

Handling POST dataNow we edit action.php (of course this file can be called whatever, as long as the form passes it on).Hi <?php echo $_POST["name"]; ?>.You are <?php echo $_POST["age"]; ?> years old.

Handling POST data$_POST[] is an autoglobal array which get’s created at every webpage by the server.Sample out put from our script would be:Hi Joe. You are 22 years old

Data TypesThere are eight data types in PHP (which isn’t a lot), I’m going to cover three, the others are not used a lot and would be considered advanced in the contexts of PHP anyways. Data types in PHP, unlike, are flexible or not strict, and are refrenced the same way, so inter-chaging is simple.

Data Types$bool = TRUE; // a boolean $str = "foo"; // a string $int = 12; // an integer echogettype($bool); // prints out"boolean" echo gettype($str); // prints out "string" // If this is an integer, increment it by fourif (is_int($int)) { $int += 4; } /* If $bool is a string, print it out (does not print out anything) */if (is_string($bool)) { echo "String: $bool"; }

Manulipating Data TypesThese types can be added, subtracted, concatinated like they can be in C or Java$a = 5;$b = 4;Echo ($a + $b); // prints 9!$string = “touch”;$end = “down”;Echo $string.$end; //prints touchdown!

Control StructuresIf:$hey = TRUE;If($hey) { printf(“Hello\n”);} else { printf(“Never gona see this!\n”);}

While$a = 0;While($a < 100) { printf(“hello $a\n”); a++;}Prints all the numbers from 0 to 99.

For & othersFor($a = 0; $a < 100; $a++){ printf(“Hello $a\n”);}//prints all the numbers from 0 to 99 againPHP has also all the other control structures you can think of, until, do, switch, : ?

Global VariablesWe’ve already seen the use of some global or Super variables in $_POST and $_SERVER. There’s a good few of them which can be useful to make your site more personal. To get a list of them, create this PHP file.#!/usr/local/bin/php<?php phpinfo(); ?>

ResourcesThis helpdesk tutorial like the others is just geared to get you started at PHP coding. PHP’s website is the best resource for consultation, www.php.net it has a simple to follow tutorial (you might find striking resemblances with tonite’s!), as well as a manual page for every function in PHP. I recommend you go to the site for more detailed descriptions of what we did tonite.

Why is PHP good?Php is good for a number of reasonsEasy to useWell documentedLarge libraryGood Database interactionGood for Projects!!See Paul Acquaro’s class this Summer.

Dynamic Web Programming

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Dynamic Web Programming