Add completion for `events --filter`

Signed-off-by: Harald Albers <github@albersweb.de>

cli/command/system/completion.go

@@ -0,0 +1,237 @@
+package system
+
+import (
+	"strings"
+
+	"github.com/docker/cli/cli/command/completion"
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/events"
+	"github.com/docker/docker/api/types/image"
+	"github.com/docker/docker/api/types/network"
+	"github.com/docker/docker/api/types/volume"
+	"github.com/spf13/cobra"
+)
+
+var (
+	eventFilters = []string{"container", "daemon", "event", "image", "label", "network", "node", "scope", "type", "volume"}
+
+	// eventTypes is a list of all event types.
+	// This should be moved to the moby codebase once its usage is consolidated here.
+	eventTypes = []events.Type{
+		events.BuilderEventType,
+		events.ConfigEventType,
+		events.ContainerEventType,
+		events.DaemonEventType,
+		events.ImageEventType,
+		events.NetworkEventType,
+		events.NodeEventType,
+		events.PluginEventType,
+		events.SecretEventType,
+		events.ServiceEventType,
+		events.VolumeEventType,
+	}
+
+	// eventActions is a list of all event actions.
+	// This should be moved to the moby codebase once its usage is consolidated here.
+	eventActions = []events.Action{
+		events.ActionCreate,
+		events.ActionStart,
+		events.ActionRestart,
+		events.ActionStop,
+		events.ActionCheckpoint,
+		events.ActionPause,
+		events.ActionUnPause,
+		events.ActionAttach,
+		events.ActionDetach,
+		events.ActionResize,
+		events.ActionUpdate,
+		events.ActionRename,
+		events.ActionKill,
+		events.ActionDie,
+		events.ActionOOM,
+		events.ActionDestroy,
+		events.ActionRemove,
+		events.ActionCommit,
+		events.ActionTop,
+		events.ActionCopy,
+		events.ActionArchivePath,
+		events.ActionExtractToDir,
+		events.ActionExport,
+		events.ActionImport,
+		events.ActionSave,
+		events.ActionLoad,
+		events.ActionTag,
+		events.ActionUnTag,
+		events.ActionPush,
+		events.ActionPull,
+		events.ActionPrune,
+		events.ActionDelete,
+		events.ActionEnable,
+		events.ActionDisable,
+		events.ActionConnect,
+		events.ActionDisconnect,
+		events.ActionReload,
+		events.ActionMount,
+		events.ActionUnmount,
+		events.ActionExecCreate,
+		events.ActionExecStart,
+		events.ActionExecDie,
+		events.ActionExecDetach,
+		events.ActionHealthStatus,
+		events.ActionHealthStatusRunning,
+		events.ActionHealthStatusHealthy,
+		events.ActionHealthStatusUnhealthy,
+	}
+)
+
+// completeEventFilters provides completion for the filters that can be used with `--filter`.
+func completeEventFilters(dockerCLI completion.APIClientProvider) completion.ValidArgsFn {
+	return func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+		key, _, ok := strings.Cut(toComplete, "=")
+		if !ok {
+			return postfixWith("=", eventFilters), cobra.ShellCompDirectiveNoSpace
+		}
+		switch key {
+		case "container":
+			return prefixWith("container=", containerNames(dockerCLI, cmd, args, toComplete)), cobra.ShellCompDirectiveNoFileComp
+		case "daemon":
+			return prefixWith("daemon=", daemonNames(dockerCLI, cmd)), cobra.ShellCompDirectiveNoFileComp
+		case "event":
+			return prefixWith("event=", validEventNames()), cobra.ShellCompDirectiveNoFileComp
+		case "image":
+			return prefixWith("image=", imageNames(dockerCLI, cmd)), cobra.ShellCompDirectiveNoFileComp
+		case "label":
+			return nil, cobra.ShellCompDirectiveNoFileComp
+		case "network":
+			return prefixWith("network=", networkNames(dockerCLI, cmd)), cobra.ShellCompDirectiveNoFileComp
+		case "node":
+			return prefixWith("node=", nodeNames(dockerCLI, cmd)), cobra.ShellCompDirectiveNoFileComp
+		case "scope":
+			return prefixWith("scope=", []string{"local", "swarm"}), cobra.ShellCompDirectiveNoFileComp
+		case "type":
+			return prefixWith("type=", eventTypeNames()), cobra.ShellCompDirectiveNoFileComp
+		case "volume":
+			return prefixWith("volume=", volumeNames(dockerCLI, cmd)), cobra.ShellCompDirectiveNoFileComp
+		default:
+			return postfixWith("=", eventFilters), cobra.ShellCompDirectiveNoSpace | cobra.ShellCompDirectiveNoFileComp
+		}
+	}
+}
+
+// prefixWith prefixes every element in the slice with the given prefix.
+func prefixWith(prefix string, values []string) []string {
+	result := make([]string, len(values))
+	for i, v := range values {
+		result[i] = prefix + v
+	}
+	return result
+}
+
+// postfixWith appends postfix to every element in the slice.
+func postfixWith(postfix string, values []string) []string {
+	result := make([]string, len(values))
+	for i, v := range values {
+		result[i] = v + postfix
+	}
+	return result
+}
+
+// eventTypeNames provides a list of all event types.
+// The list is derived from eventTypes.
+func eventTypeNames() []string {
+	names := make([]string, len(eventTypes))
+	for i, eventType := range eventTypes {
+		names[i] = string(eventType)
+	}
+	return names
+}
+
+// validEventNames provides a list of all event actions.
+// The list is derived from eventActions.
+// Actions that are not suitable for usage in completions are removed.
+func validEventNames() []string {
+	names := make([]string, 0, len(eventActions))
+	for _, eventAction := range eventActions {
+		if strings.Contains(string(eventAction), " ") {
+			continue
+		}
+		names = append(names, string(eventAction))
+	}
+	return names
+}
+
+// containerNames contacts the API to get names and optionally IDs of containers.
+// In case of an error, an empty list is returned.
+func containerNames(dockerCLI completion.APIClientProvider, cmd *cobra.Command, args []string, toComplete string) []string {
+	names, _ := completion.ContainerNames(dockerCLI, true)(cmd, args, toComplete)
+	if names == nil {
+		return []string{}
+	}
+	return names
+}
+
+// daemonNames contacts the API to get name and ID of the current docker daemon.
+// In case of an error, an empty list is returned.
+func daemonNames(dockerCLI completion.APIClientProvider, cmd *cobra.Command) []string {
+	info, err := dockerCLI.Client().Info(cmd.Context())
+	if err != nil {
+		return []string{}
+	}
+	return []string{info.Name, info.ID}
+}
+
+// imageNames contacts the API to get a list of image names.
+// In case of an error, an empty list is returned.
+func imageNames(dockerCLI completion.APIClientProvider, cmd *cobra.Command) []string {
+	list, err := dockerCLI.Client().ImageList(cmd.Context(), image.ListOptions{})
+	if err != nil {
+		return []string{}
+	}
+	names := make([]string, 0, len(list))
+	for _, img := range list {
+		names = append(names, img.RepoTags...)
+	}
+	return names
+}
+
+// networkNames contacts the API to get a list of network names.
+// In case of an error, an empty list is returned.
+func networkNames(dockerCLI completion.APIClientProvider, cmd *cobra.Command) []string {
+	list, err := dockerCLI.Client().NetworkList(cmd.Context(), network.ListOptions{})
+	if err != nil {
+		return []string{}
+	}
+	names := make([]string, 0, len(list))
+	for _, nw := range list {
+		names = append(names, nw.Name)
+	}
+	return names
+}
+
+// nodeNames contacts the API to get a list of node names.
+// In case of an error, an empty list is returned.
+func nodeNames(dockerCLI completion.APIClientProvider, cmd *cobra.Command) []string {
+	list, err := dockerCLI.Client().NodeList(cmd.Context(), types.NodeListOptions{})
+	if err != nil {
+		return []string{}
+	}
+	names := make([]string, 0, len(list))
+	for _, node := range list {
+		names = append(names, node.Description.Hostname)
+	}
+	return names
+}
+
+// volumeNames contacts the API to get a list of volume names.
+// In case of an error, an empty list is returned.
+func volumeNames(dockerCLI completion.APIClientProvider, cmd *cobra.Command) []string {
+	list, err := dockerCLI.Client().VolumeList(cmd.Context(), volume.ListOptions{})
+	if err != nil {
+		return []string{}
+	}
+	names := make([]string, 0, len(list.Volumes))
+	for _, v := range list.Volumes {
+		names = append(names, v.Name)
+	}
+	return names
+}

cli/command/system/events.go

@@ -50,6 +50,8 @@ func NewEventsCommand(dockerCli command.Cli) *cobra.Command {
 	flags.VarP(&options.filter, "filter", "f", "Filter output based on conditions provided")
 	flags.StringVar(&options.format, "format", "", flagsHelper.InspectFormatHelp) // using the same flag description as "inspect" commands for now.
 
+	_ = cmd.RegisterFlagCompletionFunc("filter", completeEventFilters(dockerCli))
+
 	return cmd
 }