This page explains how to create and configure a custom Filter.
To ensure your filter is properly registered using Magnolia configuration, your filter should implement MgnlFilter or extend another Magnolia filter which implements MgnlFilter. Extending AbstractMgnlFilter is usually a good starting point.
The example above is a dummy example inspired by GNU Terry Pratchett HTTP-Header.
Configuration and Registration of filters
Filters in a Java webapp using servlets 2.5 must be registered in the
When adding a filter to Magnolia - you should not register it in web.xml but on Magnolia configuration. If the configuration is done properly - filters are registered dynamically by Magnolia.
You can configure filters implementing MgnlFilter as well as other filters with Magnolia configuration by using Configuration app. Compared to "classical" web.xml based configuration - you can change the configuration on the running instance. This also includes enabling and disabling a filter.
As with any other configuration data - bootstrap the configuration within your module with a bootstrap file or create an installation task to ensure configuration is set correctly when your project must be reinstalled or deployed.
Add a node to
To configure a filter add a node to /server/filters:
The fully qualified class name of your custom filter (which must implement MgnlFilter ).
optional, default is
Setting to false disables the filter.
Configuring and registering a filter which does not implement info.magnolia.cms.filters.MgnlFilter
If you have a filter which can not implement MgnlFilter for some reason but which should be registered to Magnolia filter chain, your configuration should look like this:
In this case class must be info.magnolia.cms.filters.FilterDecorator.
The fully qualified class name of your custom filter (which does not implement AbstractMgnlFilter ).
A map to add filter init parameters. You may add as many parameters as required. The init parameters can be read in the init method of the filter (see below).
Adding filter init parameters
javax.servlet.Filter has an #init method which is called once when the filter is initialized.
Init parameters for filters implementing info.magnolia.cms.filters.MgnlFilter
When using filters implementing MgnlFilter you can use "normal" Node2Bean mechanism. Add bean properties to the filter class and configure appropriately:
|Klacker messages are save and reliable.|
Init parameters for filters not implementing info.magnolia.cms.filters.MgnlFilter
If you are using FilterDecorator for custom filters not implementing MgnlFilter , use the config node to add init parameters (see above). The parameters are set to javax.servlet.FilterConfig and can be used in the init method:
Ensure position in filter chain
Filters are executed in the order they are in the chain, from top to bottom. If you do not care about execution order, you can skip this section, otherwise make sure the filter is in the right position in the chain.
Magnolia provides task classes to adapt the order of the filter via module version handler. Use FilterOrderingTask or OrderFilterBeforeTask. The code example below is using the
When installing a module, you can define the position with
The code above would ensure to have the filter "klacker" right after the filter "contentType".