Web Calendar Access Protocol (WCAP) is a protocol for remote client-server calendar access and scheduling based on the

XML Extensible Markup Language (XML) is a markup language and file format for storing, transmitting, and reconstructing arbitrary data. It defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. ...

HTTP The Hypertext Transfer Protocol (HTTP) is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web, ...

iCalendar The Internet Calendaring and Scheduling Core Object Specification (iCalendar) is a media type which allows users to store and exchange calendaring and scheduling information such as events, to-dos, journal entries, and free/busy information, a ...

, and

vCard vCard, also known as VCF (Virtual Contact File), is a file format standard for electronic business cards. vCards can be attached to e-mail messages, sent via Multimedia Messaging Service (MMS), on the World Wide Web, instant messaging, NFC o ...

Internet The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a ''internetworking, network of networks'' that consists ...

standards. WCAP was created for use with the product that eventually became

Sun Java System Calendar Server The Sun Java System Calendar Server was Sun's calendar (scheduling) server. The currently available version is 6.3 which is now part of the Sun Java System Communications Suite. Users can access their calendar and task list items using a variety ...

. WCAP uses simple HTTP GET commands for accessing iCalendar, Freebusy, TODO and vCard entries. WCAP responses are either the traditional text form or an XML form of iCalendar/etc. Several plugins exist including those for

Mozilla Thunderbird Mozilla Thunderbird is a free and open-source cross-platform email client, personal information manager, news client, RSS and chat client developed by the Mozilla Foundation and operated by subsidiary MZLA Technologies Corporation. The projec ...

Novell Evolution GNOME Evolution (formerly Novell Evolution and Ximian Evolution, prior to Novell's 2003 acquisition of Ximian) is the official personal information manager for GNOME. It has been an official part of GNOME since Evolution 2.0 was included with t ...

and

Microsoft Outlook Microsoft Outlook is a personal information manager software system from Microsoft, available as a part of the Microsoft Office and Microsoft 365 software suites. Though primarily an email client, Outlook also includes such functions as c ...

.System Connector for Microsoft Outlook
/ref>

CalDAV Calendaring Extensions to WebDAV, or CalDAV, is an Internet standard allowing a client to access and manage calendar data along with the ability to schedule meetings with users on the same or on remote servers. It lets multiple users in differ ...

is a competing protocol which as of 2007 underwent standardization.{{citation needed, date=November 2022

Example

Client

GET /wcap/get_freebusy.wcap?appid=mozilla-calendar&calid=mailto%3Atom%40localhost&busyonly=1&dtstart=20070521T040000Z&dtend=20070525T040000Z&fmt-out=text%2Fxml&id=17046506 HTTP/1.1
Host: localhost:8080
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.0.10) Gecko/20070403 Thunderbird/1.5.0.10
Accept: text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip, deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Pragma: no-cache
Cache-Control: no-cache

Response

HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
X-Powered-By: Servlet 2.4; JBoss-4.0.4.GA (build: CVSTag=JBoss_4_0_4_GA date=200605151000)/Tomcat-5.5
Set-Cookie: JSESSIONID=41DAC48C79927D68EDFAF5FBFD491236; Path=/
Content-Type: text/html;charset=ISO-8859-1
Content-Length: 1399
Date: Mon, 21 May 2007 19:43:37 GMT




20061102T170639Z
20060814T110002Z
999
999
tom
tom
tom
@@o^c^WDEIC^g
@@o^a^RSF^g
@^a^rsf^g
@^c^^g
@^p^r^g
0
1

20070521T040000Z
20070525T040000Z
20070521T130000Z/20070521T140000Z20070521T150000Z/20070521T160000Z

0

References

Calendaring standards Sun Microsystems software