Apache Cocoon

1. Apache Cocoon Part II 3/6/06 Kevin Davis

2. Learning Objectives • Understand how CForms work • Understand how XSPs work • Make a basic CForm that can pass information to an XSP

3. Cocoon Forms vs HTML Forms • Cocoon forms – use XML to make reusable form objects with easy validation • HTML forms – must write all forms individually and use Javascript or other languages for some validation • See working samples at http://blaze.terry.uga.edu:8080/cocoon/samples/blocks/forms/

4. Widgets • XML entities in the definition file that give a form field its name and validation information <fd:field id="email" required="true"> <fd:label>Email address:</fd:label> <fd:datatype base="string"/> <fd:validation> <fd:email/> </fd:validation> </fd:field> • Called in the template file along with HTML code for formatting <br/> <ft:widget-label id="email"/> <ft:widget id="email"/> • Have built-in responses to validation issues, including help tooltips and redisplaying the form if something wasn’t correct

5. Flow • A Javascript file and the sitemap control the order in which pages are called function registration() { var form = new Form("registration_definition.xml"); form.showForm("registration-display-pipeline"); var viewData = { "username" : form.getChild("name").getValue() } cocoon.sendPage("registration-success-pipeline", viewData); }

6. Flow Continued <map:flow language="javascript"> <map:script src="registration.js"/> </map:flow> … <map:pipeline> <map:match pattern="registration"> <map:call function="registration"/> </map:match> … <map:match pattern="registration-display-pipeline"> <map:generate type="jx" src="registration_template.xml"/> <map:transform type="i18n"> <map:parameter name="locale" value="en-US"/> </map:transform> <map:transform src="forms-samples-styling.xsl"/> <map:serialize/> </map:match> … <map:match pattern="registration-success-pipeline"> <map:generate type="jx" src="registration_success.jx"/> <map:serialize/> </map:match>

7. XSPs • Much like servlets, XSPs can request data from a submitted form and insert it into a database, or call and display data from a database • XML tags and Java code can be used • Connection to a database occurs in one Cocoon configuration file, XSPs just need to call the name of the database

8. XSPs Continued <esql:connection> <esql:pool>otc</esql:pool> <esql:execute-query> <esql:query> INSERT into otc_users (name,email,password,age,spam) values ('<xsp:expr>esc_name</xsp:expr>','<xsp- request:get-parameter name="email"/>','<xsp- request:get-parameter name="password"/>','<xsp- request:get-parameter name="age"/>','<xsp-request:get- parameter name="spam"/>') </esql:query> </esql:execute-query> </esql:connection> … <xsp:logic> [java code] </xsp:logic>

9. Exercise • Follow the guide located at http://cocoon.apache.org/2.1/userdocs/basics/sample.html - create your own template and definition files with at least one unique widget • Compare this to the working example located at http://blaze.terry.uga.edu:8080/cocoon/cforms/registration • Look at the files sitemap-modified.xmap and test.xsp in the opt/tomcat5/webapps/cocoon/cforms directory to see how a CForm could use an XSP to insert data into a database