APIv2: Add docker compatible volume endpoints

This change implements docker compatibile endpoint for interacting with
volumes. The code is mostly lifted from the `libpod` API handlers but
decodes and constructs data using types defined in the docker API
package.

Some notable support caveats with the current implementation:
  * we don't return the nullable `Status` or `UsageData` keys when
    returning volume information for inspect and create endpoints
  * we don't support filters when pruning
  * we return a fixed `0` for the `SpaceReclaimed` key when pruning
    since we have no insight into how much space was freed from runtime

Signed-off-by: Matt Brindley <58414429+maybe-sybr@users.noreply.github.com>

pkg/domain/entities/volumes.go

@@ -2,6 +2,9 @@ package entities
 
 import (
 	"time"
+
+	docker_api_types "github.com/docker/docker/api/types"
+	docker_api_types_volume "github.com/docker/docker/api/types/volume"
 )
 
 // swagger:model VolumeCreate
@@ -90,3 +93,35 @@ type VolumeListOptions struct {
 type VolumeListReport struct {
 	VolumeConfigResponse
 }
+
+/*
+ * Docker API compatibility types
+ */
+// swagger:response DockerVolumeList
+type SwagDockerVolumeListResponse struct {
+	// in:body
+	Body struct {
+		docker_api_types_volume.VolumeListOKBody
+	}
+}
+
+// swagger:model DockerVolumeCreate
+type DockerVolumeCreate docker_api_types_volume.VolumeCreateBody
+
+// This response definition is used for both the create and inspect endpoints
+// swagger:response DockerVolumeInfoResponse
+type SwagDockerVolumeInfoResponse struct {
+	// in:body
+	Body struct {
+		docker_api_types.Volume
+	}
+}
+
+// Volume prune response
+// swagger:response DockerVolumePruneResponse
+type SwagDockerVolumePruneResponse struct {
+	// in:body
+	Body struct {
+		docker_api_types.VolumesPruneReport
+	}
+}