containerz volume driver enum

[LimeHat]

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)

gnoi/containerz/containerz.proto

Lines 636 to 645 in d04468f

	enum Driver {
	DS_UNSPECIFIED = 0;
	// Refers to the standard mount(8) built-in volume driver.
	DS_LOCAL = 1;
	// Refers to a custom volume driver that should be loaded via Plugin RPCs.
	DS_CUSTOM = 2;
	}

The field must be of type string instead (unless you intend to enumerate all possible drivers)

@robshakir @alshabib

[LarsxGitHub]

Afaics, it should be possible to specify DS_CUSTOM driver and then add CustomOptions for the name of the driver among other parameters.

[LimeHat]

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)

gnoi/containerz/containerz.proto

Lines 683 to 684 in d04468f

	// Options for the driver. The actual option keys and values are driver
	// specific.

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.

[LimeHat]

For reference here's the docker api docs:
https://github.com/moby/moby/blob/ea126c054103628f900e64046e946adf7e98148f/api/docs/v1.52.yaml#L2369-L2385