WebDAV-Servlet

What is it?

A Servlet that brings basic WebDAV access to any store. Only 1 interface (IWebdavStorage) has to be implemented, an example (LocalFileSystemStorage) which uses the local filesystem, is provided.

Unlike large systems (like slide), this servlet only supports the most basic data access options. versioning or user management are not supported

However it does support address book detection and extension for vCard (CardDav) and might even work for iCal (CalDav).

REQUIREMENTS

• JDK 1.6 or above
• A servlet container
• Apache Maven

INSTALLATION & CONFIGURATION

When used with a maven project, clone the repo and install it with maven:

git clone https://github.com/corinis/webdav-servlet.git
cd webdav-servlet
mvn install

Then in your project add the dependency:

<dependency>
	<groupId>com.corinis.external</groupId>
	<artifactId>webdav-servlet</artifactId>
	<version>2.1.0-SNAPSHOT</version>
</dependency>

This is for Apache Tomcat:

• place the webdav-servlet.jar in the /WEB-INF/lib/ of your webapp
• open web.xml of the webapp. it needs to contain the following:

  	<servlet>
		<servlet-name>webdav</servlet-name>
		<servlet-class>
			net.sf.webdav.WebdavServlet
		</servlet-class>
		<init-param>
			<description>
				name of the class that implements
				net.sf.webdav.IWebdavStore
			</description>
			<param-name>ResourceHandlerImplementation</param-name>
			<param-value>
				net.sf.webdav.LocalFileSystemStore
			</param-value>
		</init-param>
		<init-param>
			<description>
				folder where webdavcontent on the local filesystem is stored (for LocalFileSystemstore)
			</description>
			<param-name>rootpath</param-name>
			<param-value>/tmp/webdav</param-value>
		</init-param>
		<init-param>
			<description>
				triggers debug output of the
				ResourceHandlerImplementation (0 = off , 1 = on) off by default
			</description>
			<param-name>storeDebug</param-name>
			<param-value>0</param-value>
		</init-param>
	</servlet>
	<servlet-mapping>
		<servlet-name>webdav</servlet-name>
		<url-pattern>/*</url-pattern>
	</servlet-mapping>

• if you have implemented your own store, insert the class name to the parameter "ResourceHandlerImplementation" and copy your .jar to /WEB-INF/lib/
• with /* as servlet mapping, every request to the webapp is handled by the servlet. change this if you want
• with the "storeDebug" parameter you can trigger the reference store implementation to spam at every method call. this parameter is optional and can be omitted
• authentication is done by the servlet-container. If you need it, you have to add the appropriate sections to the web.xml
• you can have multiple stores on the same server with different url-patterns

Sample Stores

FILESTORE

The sample filestore allows classic webdav clients to read/write files on your servers file system.

Configuration

You need to set the LocalFileStore class and the parameter "rootpath" to where you want to store your files in your web.xml:

  	<servlet>
		<servlet-name>webdav-filestore</servlet-name>
		<init-param>
			<param-name>ResourceHandlerImplementation</param-name>
			<param-value>net.sf.webdav.LocalFileSystemStore</param-value>
		</init-param>
		<init-param>
			<param-name>rootpath</param-name>
			<param-value>/tmp/webdav</param-value>
		</init-param>
	</servlet>
	<servlet-mapping>
		<servlet-name>webdav-filestore</servlet-name>
		<url-pattern>/dav/*</url-pattern>
	</servlet-mapping>

Access

The webdav-filestore is reached at:

  "http://<ip/name + port of the server>/<name of the webapp>/<servlet-maping>"
  for the above setting: http://localhost:8080/dav/

weta-dfs-webdav has been tested on tomcat 5.0.28 and 5.5.12 so far, we accessed it from windows(2000 and XP) and MAC

CARDDAV

Carddav is an extension to the default webdav protocol for storing contact information as "vcard". The sample implementation allows for that by storing the information received onto the file system.

The store class is a little more complex with REPORT support and custom namespace extension in order to support more clients.

Note: This is not a full sync solution, but rather a simple proof of concept. It will allow you to our of the box sync the contacts of i.e. 2 computers running thunderbird.

Because of the simple core code, it will probably not work correctly if:

• if 2 computers change the same file
• multi user support
• clients use of different fields (i.e. one client supports images, the other one does not)

CALDAV

The changes allow for extension to support caldav other dav variants, but are ot bundled.

Configuration

You need to set the CardDavFileStore class and the parameter "rootpath" to where you want to store your vcards in your web.xml:

  	<servlet>
		<servlet-name>webdav-carddav</servlet-name>
		<init-param>
			<param-name>ResourceHandlerImplementation</param-name>
			<param-value>net.sf.webdav.CardDavFileStore</param-value>
		</init-param>
		<init-param>
			<param-name>rootpath</param-name>
			<param-value>/tmp/carddav</param-value>
		</init-param>
	</servlet>
	<servlet-mapping>
		<servlet-name>webdav-carddav</servlet-name>
		<url-pattern>/carddav/*</url-pattern>
	</servlet-mapping>
		

Access / Client Support

  "http://<ip/name + port of the server>/<name of the webapp>/<servlet-maping>"
  for the above configuration: http://localhost:8080/carddav

This has been tested with:

• Thunderbird and the Sogo Connector 31.0.1 (for this to work add the "/addressbook/" after the servlet mapping)
• Kontact
• Android

Most fields even sync between this clients.

CREDITS

• Remy Maucherat for the original webdav-servlet
• the dependent files that come with tomcat,
• Oliver Zeigermann for the slide-WCK. Our IWebdavStorage class is modeled after his BasicWebdavStore.

original project homepage