class MetadataServer

When converting a driver from DFv1 to DFv2, replace usages of the `ddk::MetadataServer` class

with the `fdf_metadata::MetadataServer` class found in the //sdk/lib/driver/metadata/cpp library.

Serves metadata that can be retrieved using `ddk::GetMetadata

<

|FidlType|>()`. `FidlType` must be

annotated with `

`.

As an example, lets say there exists a FIDl type `fuchsia.hardware.test/Metadata` to be sent from

a driver to its child driver:

library fuchsia.hardware.test;

// Make sure to annotate with `

`.

type Metadata = table {

1: test_property string:MAX;

};

The parent driver can define a `MetadataServer

<fuchsia

_hardware_test::Metadata>` server

instance as one its members:

class ParentDriver : public fdf::DriverBase {

private:

using MetadataServer = ddk::MetadataServer

<fuchsia

_hardware_test::Metadata>

MetadataServer metadata_server_;

}

When the parent driver creates a child device, it can offer the metadata server's service to the

child device by adding the metadata server's offers to the device-add arguments:

std::array offers = {MetadataServer::kFidlServiceName};

ddk::DeviceAddArgs args{"child"};

args.set_fidl_service_offers(offers))

The parent driver should also declare the metadata server's capability and offer it in the

driver's component manifest:

capabilities: [

{ service: "fuchsia.hardware.test.Metadata" },

],

expose: [

{

service: "fuchsia.hardware.test.Metadata",

from: "self",

},

],