The access control property is essentially only a collection of rules. As an example from a specific use case I have, users have groups or attributes assigned to them in an external system. For particular elements of data that are stored in the graph, we want to be able to say something like "to access this element, a user must have both the ONCOLOGY and SPECIALIST attributes, and at least one of the FINANCE_APPROVER or FINANCE_MANAGER attributes". This access control property is then checked against and Object representing the user's attributes and the application determines whether or not the user can perform some action. I had envisioned that, in setting up the application, the administrator could configure the specific strategy for how this access control check is resolved.
I have the code in Github in a fork from JanusGraph and here is a link to the datatype that I stored on the graph to do the filtering (https://github.com/mikelee2082/janusgraph/blob/master/janusgraph-core/src/main/java/org/janusgraph/core/attribute/Access.java). There are unit tests where I used the SubgraphStrategy in https://github.com/mikelee2082/janusgraph/blob/master/janusgraph-test/src/test/java/org/janusgraph/core/attribute/AccessAttributeTest.java. I am a very inexperienced developer and I have not yet thought about how it could be done in a way that would be language agnostic. The way I have done it at the moment depends on a client being able to create and serialize a Java object to store on the graph. At the moment, we are fairly constrained in our thinking by our use case. We are building a component that communicates with a JanusGraph server on behalf of a user. In this case, the component manages all user aspects, such as authenticating them, obtained their privileges from an external source, constructing the Gremlin query based on their query, getting the data they want and passing it back. This seems like a lot of effort, but it is an essential requirement that we only provide users with the level of detail that they are authorized to read. So in our case, the user's don't create a TraversalSource - we do that for them. Because of this, we have the option of constructing a TraversalSource that is constrained to a subgraph. Ideally, we would prefer to have users communicate with the server directly. Again, thanks for taking the time to consider my idea. I hope I have answered your questions. My solution right now is fairly primitive, so if anyone has any ideas for how it might be done differently, in a way that works for larger graphs just as well as small, I'd be really interested in giving it a go. On 2020/01/03 11:44:09, Stephen Mallette <[email protected]> wrote: > Thanks for posting your idea. As others on the list may not have seen my > post elsewhere, I'll just quickly repeat an approximation of what I wrote. > Basically, I think that users would like a feature like this, but I > wondered if it were something best left to graph providers to implement > native to their systems as an unoptimized implementation may not perform > well or behave with limited functionality. So, with that in mind, here's > some further thoughts/questions: > > 1. Could you say some more about how the "access control property" is > defined? How would you envision such a thing to be generalized across all > graphs providers? > 2. Could you share some sample code for how you define your "custom > predicate" and what the TraversalStrategy does with that (basically, please > show how all that wraps up with Gremlin)? > 3. Please keep in mind that any solution here must be portable across all > programming languages - will users be able to define the required objects > in python, javascript, etc? > 4. As I think about how users initialize a TraversalSource, I can't help > thinking that implementing this feature as a TraversalStrategy places it at > the wrong level of abstraction. The notion of a "user" who has access > rights is bound to the RemoteConnection (Cluster/Client). It is through > that method that the graph is aware of who the user is and from that > initial authenticating handshake can govern the data that the user sees. > While that thinking applies to remote graphs, it might also apply to > embedded graphs as well where the "user" is supplied by way of the > Configuration object given to the Graph instance where subsequent > TraversalSource constructs would inherit from that. > > > > > > On Thu, Jan 2, 2020 at 6:55 AM Mike Lee <[email protected]> wrote: > > > Hello > > > > Apologies if this is the incorrect forum - I was pointed here from another > > mailing list. > > > > I had an idea for an access control scheme that could be applied to > > vertices, edges or vertex properties and would allow a server to check > > whether a user has permission to retrieve or traverse that particular graph > > element. The access control property would be a set of rules outlining the > > attributes, and the combination of those attributes, that establish whether > > or not a user has sufficient privileges for that graph element. I have > > experimented with attempting to use the existing Gremlin language to do > > this, but I have so far been unable to achieve the level of fine-grained > > access control that I believe would be useful in a variety of situations. I > > have tested this with a prototype that uses a Java object and a custom > > predicate that tests a user's profile against the access control, and then > > used a traversal strategy to constrain a query to those elements which pass > > the test. > > > > I was curious as to whether people would see such a feature as something > > that could be part of Gremlin, or whether it would be better left to > > specific implementations of Tinkerpop. > > > > Thanks for your consideration. > > >
