node hand-over: the terminal hands a directory used as found to the mesh, asked of the node's engine (hq issue 356)

A module's condition told the operator to run the node-engine's hand-over at the machine, as root (issue 339), and the mesh had no channel for it. Now node hand-over <node> <path> is the controller's terminal's — a node subcommand that is not a read, so every verb and mesh-cli outside the terminal refuse it — and asks that node's engine on mesh.node.<node>.ask.hand-over, a request only the controller may publish and only that node's engine may hear and answer (its grant gains the subject and the right to answer what it was asked). The line's node and path are judged before anything is asked; the engine's answer is printed, a refusal as a refusal. Every text addressed to the operator names the nox line (ADR 0272); the condition's words stay plain.

cmd/mesh-controller/found_wait_test.go

@@ -18,7 +18,7 @@ func foundDirectory(module string, since time.Time) inventory.ResourceHealth {
 	return inventory.ResourceHealth{Module: module, Resource: module + ".data", Kind: link.KindDirectory,
 		Target: "/srv/" + module, State: link.StateUnhealthy, Since: since,
 		Reason: link.ReasonUsedAsFound + " owned by 1000:1000, mode 700, as found; root, mode 755 was declared and " +
-			"not given it — `mesh-host hand-over` at the machine hands it to the mesh"}
+			"not given it — `nox node hand-over laptop <directory>` on the control-node, with its path, hands it to the mesh"}
 }
 
 func TestADirectoryFoundBeforeTheSendIsAWaitForAPerson(t *testing.T) {

cmd/mesh-controller/handover_test.go

@@ -0,0 +1,90 @@
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// A hand-over's line is judged before anything is asked (novox/hq issue 356): a node's name and the directory's
+// absolute path exactly as the engine states it — no `..`, no doubled or trailing separator, nothing relative.
+func TestAHandOverLineIsJudgedBeforeItIsAsked(t *testing.T) {
+	for _, args := range [][]string{
+		{},
+		{"laptop"},
+		{"laptop", "/srv/notes", "extra"},
+		{"", "/srv/notes"},
+		{"--node", "/srv/notes"},
+		{"laptop", "srv/notes"},
+		{"laptop", "/srv/../etc"},
+		{"laptop", "/srv//notes"},
+		{"laptop", "/srv/notes/"},
+		{"laptop", "/srv/notes/."},
+	} {
+		if _, _, err := handOverLine(args); err == nil {
+			t.Errorf("%q was taken", args)
+		}
+	}
+	node, path, err := handOverLine([]string{"laptop", "/srv/notes"})
+	if err != nil || node != "laptop" || path != "/srv/notes" {
+		t.Fatalf("read as %q %q %v", node, path, err)
+	}
+}
+
+// Who hands over is the line's caller in the words every verb's caller is recorded in — the operator through
+// mesh-cli — or the controller's terminal when nobody is named.
+func TestAHandOverNamesWhoAsked(t *testing.T) {
+	t.Setenv(link.CallerVar, " jo through mesh-cli on anchor ")
+	if by := handOverBy(); by != "jo through mesh-cli on anchor" {
+		t.Fatalf("by %q", by)
+	}
+	t.Setenv(link.CallerVar, "")
+	if by := handOverBy(); by != "the controller's terminal" {
+		t.Fatalf("by %q", by)
+	}
+}
+
+// **A hand-over is the controller's terminal's alone** (novox/hq issue 356, ADR 0266): through any verb, and
+// through mesh-cli outside the terminal, `node hand-over` is refused and nothing runs — at the next apply root
+// gives the directory to the account the module declares, and whoever may call a verb includes agents.
+func TestAHandOverIsRefusedThroughEveryVerb(t *testing.T) {
+	line := []string{"node", "hand-over", "laptop", "/srv/notes"}
+	if err := terminalOnly(line); err == nil {
+		t.Fatal("node hand-over passed as a verb's line")
+	}
+	if _, err := argvFor("command", map[string]any{"command": "node hand-over laptop /srv/notes"}); err == nil {
+		t.Fatal("the command verb composed node hand-over")
+	}
+	if _, err := ordinaryLine(line); err == nil {
+		t.Fatal("node hand-over composed as an ordinary mesh-cli line")
+	}
+	if _, err := argvFor("node", map[string]any{"node": "laptop", "hand-over": "/srv/notes"}); err == nil {
+		t.Fatal("the node verb composed a hand-over")
+	}
+}
+
+// The condition's words are plain and name no machine's binary; the operator's line, with the node and the path
+// (novox/hq ADR 0272), is in the summary the module's health gives (moduleHealthWord) and in the evidence.
+func TestTheUsedAsFoundConditionNamesTheOperatorsLine(t *testing.T) {
+	rs := []inventory.ResourceHealth{foundDirectory("notes", time.Now().Add(-24*time.Hour))}
+	o := usedAsFoundObservation("notes", "laptop", "notes on laptop uses notes.data as found", rs)
+	if strings.Contains(o.Needs, "mesh-host") || strings.Contains(o.Explanation, "mesh-host") ||
+		!strings.Contains(o.Needs, "control-node") {
+		t.Fatalf("the condition's words: %q %q", o.Needs, o.Explanation)
+	}
+	if why, ok := conditions.PlainWords(conditions.Words{Headline: o.Headline, Explanation: o.Explanation, Needs: o.Needs,
+		Resolved: o.Resolved}, "laptop"); !ok {
+		t.Fatalf("not plain: %s", why)
+	}
+	f := gateFacts{now: time.Now(), health: map[string]inventory.NodeHealth{"laptop": {Node: "laptop", HeardAt: time.Now(),
+		Resources: rs}}}
+	h, why := moduleHealthWord("notes", "laptop", time.Now().Add(-time.Hour), f)
+	if h != healthPerson || !strings.Contains(why, "`nox node hand-over laptop <directory>` on the control-node") ||
+		strings.Contains(why, "mesh-host") || strings.Contains(why, "/srv/") {
+		t.Fatalf("the module's health reads %v %q; want the operator's line", h, why)
+	}
+}

cmd/mesh-controller/module_health.go

@@ -556,8 +556,8 @@ func moduleHealthWord(module, machine string, since time.Time, f gateFacts) (hea
 			said = append(said, wait)
 		}
 		if len(found) > 0 {
-			said = append(said, fmt.Sprintf("on %s, %s uses %s as found and waits for a person to hand it over "+
-				"(`mesh-host hand-over <directory>` at the machine)", machine, module, strings.Join(found, ", ")))
+			said = append(said, fmt.Sprintf("on %s, %s uses %s as found and waits for the operator to hand it over "+
+				"(`nox node hand-over %s <directory>` on the control-node)", machine, module, strings.Join(found, ", "), machine))
 		}
 		return healthPerson, strings.Join(said, "; ")
 	}
@@ -678,7 +678,9 @@ func usedAsFoundObservation(module, node, said string, rs []inventory.ResourceHe
 	o.Explanation = fmt.Sprintf("A directory of %s was already on %s, with another owner or mode than %s declares. "+
 		"The mesh left it as it was rather than hand it to an account, so %s may not be able to use it.",
 		module, node, module, module)
-	o.Needs = fmt.Sprintf("on %s, run mesh-host hand-over with the directory's path as root.", node)
+	// Plain words (ADR 0253): the line itself — `nox node hand-over <node> <path>` on the control-node (ADR 0272,
+	// issue 356) — is in the summary and the evidence, which name the directory; a path is never in these.
+	o.Needs = "hand the directory over from the control-node, as the operator; the details name it and the line to type."
 	o.Resolved = fmt.Sprintf("%s's directory on %s is the mesh's", module, node)
 	o.Actions = nil
 	return o

cmd/mesh-controller/network.go

@@ -426,10 +426,10 @@ func overlayShow(ctx context.Context, open *stores) error {
 				tunnel.Interface, tunnel.Range, tunnel.Port)
 		case n.Hub && hubName == n.Name && tunnel.Interface != "":
 			fmt.Printf("  hub — found a tunnel on %s and did NOT take it over: its key is not the tunnel's; "+
-				"`mesh-host overlay take --tunnel %s` on the machine takes it", tunnel.Interface, tunnel.Interface)
+				"`nox-mesh-host overlay take --tunnel %s` on the machine takes it", tunnel.Interface, tunnel.Interface)
 		case n.Hub:
 			fmt.Print("  hub — found no tunnel; if the machine runs the predecessor's, " +
-				"`mesh-host overlay take --tunnel <iface>` there adopts it (novox/hq ADR 0105)")
+				"`nox-mesh-host overlay take --tunnel <iface>` there adopts it (novox/hq ADR 0105)")
 		case !n.Reachable():
 			fmt.Print("  not dialable")
 		}

cmd/mesh-controller/nodes.go

@@ -10,6 +10,7 @@ import (
 	"io"
 	"net"
 	"os"
+	"path/filepath"
 	"strings"
 	"time"
 
@@ -17,6 +18,7 @@ import (
 	"github.com/novox/mesh-controller/internal/catalogue"
 	"github.com/novox/mesh-controller/internal/conditions"
 	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
 	"github.com/novox/mesh-controller/internal/token"
 )
 
@@ -28,7 +30,7 @@ import (
 
 func nodeCommand(ctx context.Context, args []string) error {
 	if len(args) == 0 {
-		return errors.New("node add <name>, node list, node show <name>, or " + publicDomainUsage)
+		return errors.New("node add <name>, node list, node show <name>, " + publicDomainUsage + ", or " + handOverUsage)
 	}
 	open, err := openStores(ctx)
 	if err != nil {
@@ -112,11 +114,82 @@ func nodeCommand(ctx context.Context, args []string) error {
 		// an optional second argument is the home when it is not /home/<account>.
 		return nodeAccount(ctx, inv, args[1:])
 
+	case "hand-over":
+		// A directory the node-engine uses as found, handed to the mesh (novox/hq issue 356, issue 339). Here, at
+		// the controller's terminal, and nowhere else: at the next apply root gives the directory to the account
+		// the module declares, and whoever may call a verb includes agents.
+		return nodeHandOver(ctx, inv, args[1:])
+
 	default:
-		return fmt.Errorf("node has no %q; it has add, list, show, public-domain, account and agent-account", args[0])
+		return fmt.Errorf("node has no %q; it has add, list, show, public-domain, account, agent-account and hand-over", args[0])
 	}
 }
 
+const handOverUsage = "node hand-over <node> <directory> — hand a directory the node-engine on <node> uses as found " +
+	"to the mesh: its next apply gives it the declared owner and mode. The directory's absolute path, as the module's " +
+	"condition names it"
+
+// handOverLine reads a hand-over's line: the node and the directory's absolute path, exactly as the engine states
+// it. Judged before anything is asked, and judged again by the engine, which is the one that acts.
+func handOverLine(args []string) (node, path string, err error) {
+	if len(args) != 2 {
+		return "", "", errors.New(handOverUsage)
+	}
+	node, path = args[0], args[1]
+	if node == "" || strings.HasPrefix(node, "-") {
+		return "", "", fmt.Errorf("%q is not a node's name; %s", node, handOverUsage)
+	}
+	if !filepath.IsAbs(path) {
+		return "", "", fmt.Errorf("%q is not an absolute path; %s", path, handOverUsage)
+	}
+	if filepath.Clean(path) != path {
+		return "", "", fmt.Errorf("%q is not the directory's path as the engine states it (no `..`, no doubled or "+
+			"trailing separator); %s", path, handOverUsage)
+	}
+	return node, path, nil
+}
+
+// handOverBy is who hands the directory over, in the words a verb's caller is recorded in: the operator through
+// mesh-cli on the control-node, or whoever runs this controller's binary at its terminal.
+func handOverBy() string {
+	if by := strings.TrimSpace(os.Getenv(link.CallerVar)); by != "" {
+		return by
+	}
+	return "the controller's terminal"
+}
+
+// nodeHandOver asks the node's engine to take a directory it uses as found as the mesh's, and says what came of
+// it. The engine records the hand-over or refuses; nothing is recorded here, because the directory is the
+// machine's and the engine is the one that reads it.
+func nodeHandOver(ctx context.Context, inv *inventory.Inventory, args []string) error {
+	node, path, err := handOverLine(args)
+	if err != nil {
+		return err
+	}
+	if _, err := inv.NodeByName(ctx, node); err != nil {
+		return err
+	}
+	address, err := broker.BusAddress()
+	if err != nil {
+		return err
+	}
+	js, err := broker.Dial(address)
+	if err != nil {
+		return fmt.Errorf("cannot reach the bus, so nothing was asked of %s: %w", node, err)
+	}
+	defer js.Close()
+	answer, err := link.AskHandOver(ctx, js.Conn(), node, path, handOverBy(), link.HandOverWithin)
+	if err != nil {
+		return err
+	}
+	if answer.Refused != "" {
+		return fmt.Errorf("%s refused: %s", node, answer.Refused)
+	}
+	fmt.Println(answer.Said)
+	fmt.Printf("  the module's condition clears once %s applies; `nox push %s` applies it now\n", node, node)
+	return nil
+}
+
 // addNode creates a node record, adopted when the operator says so (novox/hq ADR 0100).
 func addNode(ctx context.Context, inv *inventory.Inventory, args []string) error {
 	set := flag.NewFlagSet("node add", flag.ContinueOnError)