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/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)
+	}
+}