The Runnable FileSystem Resource RunnableFileSystemResource type is just like a file system resource, with the addition that, when configured as input to a reloadable service, it will call code that you supply prior to checking whether the service needs to be refreshed. This gives you the ability to be involved prior to a service being updated.
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There is no custom syntax available to configure this resource. The class name is net.shibboleth.extshared.spring.resource.RunnableFileSystemResource. It has all the same methods as the standard Spring FileSystemResource, but the constructors are different, taking a second parameter with name "runnable"
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Connect to a database to refresh the file
Reach across the network (using a protocol other than HTTP) to refresh the resource
By a script - the ScriptedRunnable is described below.
ScriptedRunnable
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