问题
I would like to know if the following scenario is possible:
A Fiware Orion Context Broker instance, to which different data providers connect to publish their data. For each data item (context), the particular data provider should be able to control which application or data consumer is allowed to subscribe to this context. Is this possible with Orion? How can this be done?
I've looked into the multitenant model, but I guess that is not the proper way to do this. Am I right? Are there any alternatives? You can protect the Orion instance with a PEP proxy, but I guess it does not allow access control on a per subscription basis.
Any hints would be highly appreciated.
回答1:
The scenario that you propose can be implemented, if I understood correctly, with Steelskin PEP Proxy and the multitenant mechanism (but with some concerns).
In your scenario, your whole application would be a service (indicated in all transactions with the fiware-service), and each data-provider would own a dedicated subservice (indicated with the fiwareservicepath header). All the users (both administrator from the data-providers and final user and applications) would be users of that service. Using XACML, different permissions can be assigned to each possible action and user in different roles. E.g.: you can create a dataProvider role with full permissions under its subservice and a dataConsumer role that should be able just to subscribe and read.
This scenario has some problems, mainly concerning who creates the users and roles and assign roles to users. In order to use Steelskin, you have to map services to Keystone Domains and subservices to Keystone Projects; and users belong to the domain. It's the domain (service) administrator the one in charge of creating the users, so, in your case, data providers would not be able to create new users (and probably, even assigning them as subservice customers).
If you need an example on how to connect these pieces together to achieve this, take a look at:
https://github.com/telefonicaid/fiware-pep-steelskin/blob/master/keystoneInstallation.md
Hope it helps
来源：https://stackoverflow.com/questions/35487847/fiware-orion-access-control-on-a-per-subscription-basis