Hi TSC ex-colleagues,

As I promised, here is a list of topics for ODL modernization. This is all that came to my mind now but it could be more, the goal here is really to trigger some brainstorm and discussion.

1) Use cases:

Our YANG based platform made it easy for ODL to become the SDN controller of choice for HW devices supporting NETCONF and other control protocols like BGP-LS, PCEP, OPENFLOW where multi-vendor is important. However it made it hard to have a role in the cloud where YANG and protocols like NETCONF, BGP-LS, PCEP are almost not existent and multi-vendor is not that important. Now, given the amount of money and effort that is currently put in the cloud, it would make sense for ODL to at least participate in some cloud use case. For example, I believe ODL can still play some role in the hybrid cloud use case where HW devices need to talk to cloud devices, ODL could take care of the HW devices while another open source controller could take care of the cloud devices.

2) SW Platform:

The OSGI/Karaf platform was state-of-the-art 10 years back where there was no real micro-services platforms like K8s, but now it is just obsolete. In the new paradigm of micro-services, applications are loose-coupled and they are mostly self-contained (e.g. run their own processes within a container) although they can share some common resources like a database, a message broker, an API gateway, etc.

For ODL to fit in the new paradigm, we would need to:

- Replace ODL distribution with ODL applications that can run in their own container: NETCONF, BGP, PCEP, TPCE, etc
- Consolidate kernel repos and jars: Existing ODL applications share a common code called kernel. Today we have ~6 repositories and a bunch of jars for the kernel where there is a single person/organization maintaining the code.
- Replace Karaf/OSGI framework with something more actual to plumb the java code and jars together (e.g. spring).

3) Infrastructure:

Here is kind of obsolete too. Some ideas to renew the build and test infrastructure:

Build pipeline:
- Move from JJB (not maintained anymore) to Jenkins pipelines or similar (work is ongoing).
- Move to a continuous release process where a merge in master produces a new release in the artifact repository (staging). This simplifies a lot the release process: just move artifacts from staging to release repository.
- Every ODL application (NETCONF, BGP, PCEP, TPCE, etc) should generate a container automatically after a merge in master. We should be testing this vs ODL distribution.

System test:
-  Robot was the best open source system test framework 10 years back where organizations had developers and system engineers separated. Things have changed a lot since and many agile organizations nowadays have developers doing system integration and system test code apart from writing product features. Robot framework is good for system integrators with basic or non coding skills but bad for developers that have to ramp up in a new language that soon find very limiting. This is why I think at this moment it would be good to switch to something like pytest for example.
- Leverage K8s to do multi-application and scale testing.

BR/Luis