CSI: display plugin capabilities in verbose status

The behaviors of CSI plugins are governed by their capabilities as
defined by the CSI specification. When debugging plugin issues, it's
useful to know which behaviors are expected so they can be matched
against RPC calls made to the plugin allocations.

Expose the plugin capabilities as named in the CSI spec in the `nomad
plugin status -verbose` output.

command/plugin_status_csi.go

@@ -105,9 +105,105 @@ func (c *PluginStatusCommand) csiFormatPlugin(plug *api.CSIPlugin) (string, erro
 		return formatKV(output), nil
 	}
 
+	full := []string{formatKV(output)}
+
+	if c.verbose {
+		controllerCaps := c.formatControllerCaps(plug.Controllers)
+		if controllerCaps != "" {
+			full = append(full, c.Colorize().Color("\n[bold]Controller Capabilities[reset]"))
+			full = append(full, controllerCaps)
+		}
+		nodeCaps := c.formatNodeCaps(plug.Nodes)
+		if nodeCaps != "" {
+			full = append(full, c.Colorize().Color("\n[bold]Node Capabilities[reset]"))
+			full = append(full, nodeCaps)
+		}
+	}
+
 	// Format the allocs
 	banner := c.Colorize().Color("\n[bold]Allocations[reset]")
 	allocs := formatAllocListStubs(plug.Allocations, c.verbose, c.length)
-	full := []string{formatKV(output), banner, allocs}
+	full = append(full, banner)
+	full = append(full, allocs)
 	return strings.Join(full, "\n"), nil
 }
+
+func (c *PluginStatusCommand) formatControllerCaps(controllers map[string]*api.CSIInfo) string {
+	caps := []string{}
+	for _, controller := range controllers {
+		switch info := controller.ControllerInfo; {
+		case info.SupportsCreateDelete:
+			caps = append(caps, "CREATE_DELETE_VOLUME")
+			fallthrough
+		case info.SupportsAttachDetach:
+			caps = append(caps, "CONTROLLER_ATTACH_DETACH")
+			fallthrough
+		case info.SupportsListVolumes:
+			caps = append(caps, "LIST_VOLUMES")
+			fallthrough
+		case info.SupportsGetCapacity:
+			caps = append(caps, "GET_CAPACITY")
+			fallthrough
+		case info.SupportsCreateDeleteSnapshot:
+			caps = append(caps, "CREATE_DELETE_SNAPSHOT")
+			fallthrough
+		case info.SupportsListSnapshots:
+			caps = append(caps, "CREATE_LIST_SNAPSHOTS")
+			fallthrough
+		case info.SupportsClone:
+			caps = append(caps, "CLONE_VOLUME")
+			fallthrough
+		case info.SupportsReadOnlyAttach:
+			caps = append(caps, "ATTACH_READONLY")
+			fallthrough
+		case info.SupportsExpand:
+			caps = append(caps, "EXPAND_VOLUME")
+			fallthrough
+		case info.SupportsListVolumesAttachedNodes:
+			caps = append(caps, "LIST_VOLUMES_PUBLISHED_NODES")
+			fallthrough
+		case info.SupportsCondition:
+			caps = append(caps, "VOLUME_CONDITION")
+			fallthrough
+		case info.SupportsGet:
+			caps = append(caps, "GET_VOLUME")
+			fallthrough
+		default:
+		}
+		break
+	}
+
+	if len(caps) == 0 {
+		return ""
+	}
+
+	return strings.Join(caps, "\n\t")
+}
+
+func (c *PluginStatusCommand) formatNodeCaps(nodes map[string]*api.CSIInfo) string {
+	caps := []string{}
+	for _, node := range nodes {
+		switch info := node.NodeInfo; {
+		case info.RequiresNodeStageVolume:
+			caps = append(caps, "STAGE_UNSTAGE_VOLUME")
+			fallthrough
+		case info.SupportsStats:
+			caps = append(caps, "GET_VOLUME_STATS")
+			fallthrough
+		case info.SupportsExpand:
+			caps = append(caps, "EXPAND_VOLUME")
+			fallthrough
+		case info.SupportsCondition:
+			caps = append(caps, "VOLUME_CONDITION")
+			fallthrough
+		default:
+		}
+		break
+	}
+
+	if len(caps) == 0 {
+		return ""
+	}
+
+	return "  " + strings.Join(caps, "\n  ")
+}