| commit | 55395808797f47aa2169f6b50b59989a3bf78bad | [log] [tgz] |
|---|---|---|
| author | Peter K. Lee <peter@intercloud.net> | Fri Jul 15 18:25:40 2016 -0700 |
| committer | Peter K. Lee <peter@intercloud.net> | Fri Jul 15 18:25:40 2016 -0700 |
| tree | 66e16b689b706fc9d28937e48c62d5b65e02e6a4 | |
| parent | 3145d0309ae49d79e2cabf280afcc4a88e7b7aad [diff] |
moved YANG schema files from root folder into ./schema directory, introduced package.json to prepare for adding code bindings, fix minor issues with YANG schema validation
YANG data models for CORD
This is a work-in-progress effort to create YANG data models for the CORD project.
You may contact Larry Peterson llp@onlab.us and/or Peter Lee peter@corenova.com if any questions.
$ npm install yang-cord
This YANG module will be the primary YANG module that will house all XOS related models going forward. The models for these came from xos/core/models directory in the XOS repository. It will eventually house the Service class, the Tenant class, etc. One notable convention here is the existence of the /api/tenant/cord and /api/service configuration tree inside this module. In a sense, I'm considering this YANG module to be the master module that all other modules derive from and augments into this module. You can see this augment behavior in the cord-subscriber.yang schema.
For now, I've captured the TenantRoot and Subscriber classes.
This YANG module is based on the CordDevice class found inside the subscriber.py (API) module implementation. I think this particular model is rather under-developed, and not placed in the right place (shouldn't be inside subscriber.py which should really just be the controller definitions). This module has a potential to be leveraged more effectively if the goal is for this to become one the the core CORD models from which other devices inherit from (which I'm guessing it will be).
This module contains the heart of the initial modeling exercise. It captures the CORD Subscriber data model (which extends XOS Subscriber model, which extends XOS TenantRoot model). There are two primary models: grouping subscriber and grouping subscriber-controller.
The 'subscriber' model extends the xos:subscriber (from the xos-core.yang) and mirrors as closely as possible the CordSubscriberRoot class. Some deviations were largely around the variable name convention where I've replaced all underscore with a dash (upload_speed is now upload-speed). This is largely to comply with YANG convention where the schema is used to model XML element structure and underscores are not really used in XML based representations (not even sure if it is valid...).
The other key deviation is in the organization of the various attributes. Instead of having a simple flat list of properties, I've grouped them into related 'services' (pseudo-JSON below):
services: { cdn: { enabled: true }, firewall: { enabled: true, rules: [] }, url-filter: { enabled: true, level: 'PG', rules: [] } uverse: { enabled: true } }
Eventually, I think these four hard-coded services will be moved out of the cord-subscriber data model altogether. I'm not sure what "on-boarded" services actually implement these features but it should be augmented by those individual service's YANG models into the cord-subscriber data model.
I've internally debated creating this controller model because I thought that the necessary attributes were rather effectively captured in the prior grouping subscriber schema definition. But the presence of the related object container in the controller (that shouldn't be in the underlying model) convinced me to model it according to the CordSubscriberNew class found inside api/tenant/cord/subscriber.py. This subscriber-controller model extends the subscriber model (inheriting all its attributes) and introduces the additional containers for features, identity, and related. Since the main function of the subscriber-controller model is to essentially layer a view-like overlay on top of the underlying cord-subscriber model, I've introduced a new custom extension construct called node:link. This is to capture the fact that the various attributes being expressed are simply a reference link to the exact same data that is located at a different place within the same object.
One note on the related object, it is currently a placeholder container and I expect it will remain that way as part of the model. The reason is, the attributes that are currently mapped inside all come from the VOLT service (which then has other attributes from VSG service, etc.). When we get to the step of modeling the various Service entities, we'll capture the necessary augment behavior in those separate YANG modules (i.e. cord-service-volt.yang, cord-service-vsg.yang, etc.).
There are two main entry-points on the subscriber instances. I've defined a list subscriber construct directly in the module cord-subscriber which basically uses the grouping subscriber-controller data model. This means that the cord-subscriber YANG module itself will be the authorative holder of all subscriber instances. Subsequently, I've augmented the xos module at the /api/tenant/cord configuration tree to have a node:link to the subscriber list within the cord-subscriber YANG module. This convention makes it possible to access the subscriber instances by directly accessing the cord-subscriber module, such as /restconf/cord-subscriber:subscriber or via the xos module, such as /restconf/xos-core:api/tenant/cord/subscriber. We'll discuss this topic further.
To run the test suite, first install the dependencies, then run npm test:
$ npm install $ npm test
Coming soon...