[Best Practice Doc] Dependency description in OAM

[resouer]

trafficstars

First of all, OAM is not an orchestration system so handling dependency is not a concern of OAM spec.

The intention of this issue is raising a need for another "Best Practice Doc" to answer the question: "Hey, how can I describe dependency in OAM?" That is said, the dependency is expected to be handled in implementations whether by DIY graph engine, or by projects like Argo/Tekton etc. The best practice is only about how to "describe" dependencies in OAM yaml files.

Actually, @hongchaodeng has already drafted an excellent Dependency Story in OAM, so the only task is translating it to markdown and host it in "Best Practice Doc" dir.

Should be quick :-)

[ryanzhang-oss]

I prefer OAM spec to define dependencies. We can also borrow concepts from CNCF serverless WG's workflow (https://github.com/cncf/wg-serverless/tree/master/workflow/spec) definition so that we don't need to reinvent the wheel

[wonderflow]

Tacking https://github.com/oam-dev/spec/pull/326

I sugguest we close this one and talk about it at https://github.com/crossplane/oam-kubernetes-runtime/issues/11