openconfig
containerz volume driver enum
Currently volume drivers are defined as enum but this makes it impossible to use a custom driver (plugins have names and there's no field to specify the name) https://github.com/openconfig/gnoi/blob/d04468fba8d73905e7865fcfd0076a48523f71e6/containerz/containerz.proto#L636-L645
The field must be of type string instead (unless you intend to enumerate all possible drivers)
@robshakir @alshabib
Afaics, it should be possible to specify DS_CUSTOM driver and then add CustomOptions for the name of the driver among other parameters.
Current definition implies that the options are opaque to the gnoi speaker and only passed to the driver itself (It is also how it is used in Docker) https://github.com/openconfig/gnoi/blob/d04468fba8d73905e7865fcfd0076a48523f71e6/containerz/containerz.proto#L683-L684
While your statement is technically correct, it will be a very odd construct (allocating a fixed option name that gnoi server should parse and strip from the other options).
I'd suggest doing it the right way.
For reference here's the docker api docs: https://github.com/moby/moby/blob/ea126c054103628f900e64046e946adf7e98148f/api/docs/v1.52.yaml#L2369-L2385