Adding New Filesystem Nodes

Note: this howto requires some knowledge of Ruby.

Any object can be included in the RVC filesystem ("inventory") as long as it implements the interface defined by RVC::InventoryObject in lib/rvc/inventory.rb. Including this module into your object is the simplest way to implement most of the methods, and all subclasses of VIM::ManagedEntity already do this. All you need to do then is write a children method which returns a hash of child objects keyed by their names.

RVC uses the RbVmomi extension mechanism to add methods to VIM classes. Just add a file with the name of the class plus an ".rb" extension to the directory lib/rvc/extensions/. In there, reopen the class you wish to modify and add your methods. See the ClusterComputeResource.rb extension for an example.

Often you'll want to put child nodes in a directory underneath an existing node instead of making them its direct children. The ClusterComputeResource.rb extension uses the convenient RVC::FakeFolder class to do this. FakeFolder's constructor takes an object and a method name. It will route calls to its children method to the object and method you supply. Thus, the "hosts" folder of a ClusterComputeResource gets its children from the rvc_host_children method on the cluster.

The RVC::Util.collect_children utility function is an efficient way to retrieve managed entities and their names from an array property. It takes as arguments a managed object and a property path, and returns a hash from names to managed entities.