Using Licenses

Each license type has a unique address. This address is used when applying a license to a node in the ContentGraph.

NOTE: Licenses can only be attached and configured by a user acting on behalf of the owner of the corresponding node.

The ContentGraph has two methods that take this address as input:

• setAccessAuth(bytes32 id, address accessAuth): sets a license from its address to be used to authenticate access.
• setReferenceAuth(bytes32 id, address referenceAuth): sets a license from its address to be used to authenticate the creation of a reference node of the asset.

Once a license has been attached it needs to be configured. See each license page for specific details on configuration.

Delegation of Auth for Access and reference

It is not a requirement for each node to be licensed. The ContentGraph is based on ERC6150 (opens in a new tab) which means that the structure of nodes in the graph are hierarchial.

If a node does not have a license set, it will delegate to it's parent node.

The auth delegation can be explained by the following pseudocode:

function auth(node, user, rejected=false):
    accessAuth = accessAuth of node
    parent = parent of node
 
    if accessAuth is not set:
        if parent is not set:
            return not rejected
        else:
            return auth with parent, user, rejected
    else:
        authorized = call auth on license with id, user
        if authorized:
            return true
        else:
            if parent is root:
                return false
            return auth with parent, user, true

This delegation allows for a variety of configurations, broad licensing high in the ContentGraph, or fine grained licenses on each Asset node.