Merge pull request #31989 from aaronlehmann/node-ps-outside-swarm-mode

cli: Wrong error message from "node ps" outside swarm mode

command/node/cmd.go

@@ -1,6 +1,9 @@
 package node
 
 import (
+	"errors"
+
+	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/cli"
 	"github.com/docker/docker/cli/command"
 	apiclient "github.com/docker/docker/client"
@@ -38,6 +41,16 @@ func Reference(ctx context.Context, client apiclient.APIClient, ref string) (str
 		if err != nil {
 			return "", err
 		}
+		if info.Swarm.NodeID == "" {
+			// If there's no node ID in /info, the node probably
+			// isn't a manager. Call a swarm-specific endpoint to
+			// get a more specific error message.
+			_, err = client.NodeList(ctx, types.NodeListOptions{})
+			if err != nil {
+				return "", err
+			}
+			return "", errors.New("node ID not found in /info")
+		}
 		return info.Swarm.NodeID, nil
 	}
 	return ref, nil

command/node/inspect_test.go

@@ -50,7 +50,7 @@ func TestNodeInspectErrors(t *testing.T) {
 				return swarm.Node{}, []byte{}, errors.Errorf("error inspecting the node")
 			},
 			infoFunc: func() (types.Info, error) {
-				return types.Info{}, nil
+				return types.Info{Swarm: swarm.Info{NodeID: "abc"}}, nil
 			},
 			expectedError: "error inspecting the node",
 		},

command/node/ps.go

@@ -95,9 +95,11 @@ func runPs(dockerCli command.Cli, opts psOptions) error {
 		}
 	}
 
+	if len(errs) == 0 || len(tasks) != 0 {
 		if err := task.Print(dockerCli, ctx, tasks, idresolver.New(client, opts.noResolve), !opts.noTrunc, opts.quiet, format); err != nil {
 			errs = append(errs, err.Error())
 		}
+	}
 
 	if len(errs) > 0 {
 		return errors.Errorf("%s", strings.Join(errs, "\n"))