Let a provider serve its consumers its own composed names (hq ADR 0346, issue 624)

The forge writes every package tarball at its public name, and its
consumers had no source for that name but a second copy kept by hand,
though the mesh composes it for the forge's route. A served value may now
name the provider's own names; a name its machine does not compose leaves
the key out, and the plan says so.

cmd/mesh-controller/plan.go

@@ -289,9 +289,15 @@ func theRestOfTheMesh(ctx context.Context, inv *inventory.Inventory,
 			continue
 		}
 		caps, _ := inv.ProfileOf(ctx, n.Name)
+		// Its public domain too (novox/hq ADR 0346): a provider elsewhere serves its own composed names,
+		// and composes them as its own plan does, under its own domain.
+		domain, err := inv.PublicDomainOf(ctx, n.Name)
+		if err != nil {
+			return catalogue.World{}, err
+		}
 		others = append(others, candidate{
 			catalogue.Node{Name: n.Name, Site: siteOf[n.Name], Capabilities: caps,
-				At: onNetwork[n.Name]}, theirs})
+				At: onNetwork[n.Name], PublicDomain: domain}, theirs})
 	}
 
 	offered := map[string][]catalogue.Provider{}
@@ -314,8 +320,18 @@ func theRestOfTheMesh(ctx context.Context, inv *inventory.Inventory,
 				if err != nil {
 					return catalogue.World{}, err
 				}
+				// And its own composed names, as that node composes them (novox/hq ADR 0346): a name it
+				// does not compose leaves the key out, said under each consumer's need.
+				layers, err := inv.SettingsFor(ctx, o.node.Name, m.Module)
+				if err != nil {
+					return catalogue.World{}, err
+				}
+				serves, leftOut, err := got.ServedOwnNames(m, name, serves, catalogue.WithDefaults(m, layers))
+				if err != nil {
+					return catalogue.World{}, err
+				}
 				offered[name] = append(offered[name], catalogue.Provider{
-					Node: o.node.Name, At: o.node.At, Serves: serves, Module: m.Module})
+					Node: o.node.Name, At: o.node.At, Serves: serves, Module: m.Module, LeftOut: leftOut})
 			}
 		}
 	}
@@ -1426,6 +1442,16 @@ func planCommand(ctx context.Context, args []string) error {
 	// in this output would have told anybody that.
 	for _, n := range plan.Needs {
 		fmt.Printf("  needs %s from %s, for %s\n", n.Name, n.From, n.For)
+		// And a served key the provider left out, because its machine composes no name it asks for
+		// (novox/hq ADR 0346 §3).
+		for _, line := range n.LeftOut {
+			fmt.Printf("    %s\n", line)
+		}
+	}
+	// What the providers on this machine leave out of what they serve, and why: said where the remedy
+	// is (novox/hq ADR 0346 §3).
+	for _, line := range plan.ServedLeftOut(settings) {
+		fmt.Printf("%s: %s\n", args[0], line)
 	}
 	for _, line := range unboundLines(plan) {
 		fmt.Println(line)

cmd/mesh-controller/served_own_names_test.go

@@ -0,0 +1,60 @@
+package main
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+)
+
+// novox/hq ADR 0346, issue 624: a provider on another machine serves its consumers its own composed
+// names, as that machine composes them; one it does not compose is left out, said under the need.
+func TestAProviderElsewhereServesItsOwnComposedName(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	forge, err := catalogue.ParseManifest([]byte(`{"module":"forge","version":"1","requires":["route"],
+	  "provides":[{"name":"npm-package-registry","scope":"mesh"}],
+	  "contributes":{"route":{"web":{"label":"git","port":3000}}},
+	  "serves":{"npm-package-registry":{"scheme":"http","port":3000,"npm-path":"/api/packages/novox/npm/",
+	    "public-root":"https://${bound:route:name-web}/api/packages/novox/npm/"}}}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	register(t, open, catalogue.Manifest{Module: "proxy", Version: "1", Provides: catalogue.FromAnywhere("route"),
+		Receives: map[string]string{"route": "/var/lib/proxy/routes.json"}})
+	register(t, open, forge)
+	register(t, open, catalogue.Manifest{Module: "lab", Version: "1", Requires: []string{"npm-package-registry"},
+		Binds: map[string]string{"npm-package-registry": "/var/lib/lab/package-registry.json"}})
+	for _, a := range [][2]string{{"anchor", "proxy"}, {"anchor", "forge"}, {"laptop", "lab"}} {
+		if _, err := assign(ctx, open, a[0], a[1]); err != nil {
+			t.Fatalf("assign %s %s: %v", a[0], a[1], err)
+		}
+	}
+
+	if err := open.inventory.SetPublicDomain(ctx, "anchor", "example.test"); err != nil {
+		t.Fatal(err)
+	}
+	plan, _, err := planFor(ctx, open, "laptop")
+	if err != nil {
+		t.Fatal(err)
+	}
+	n := need(t, plan, "lab", "npm-package-registry")
+	if n.Serves["public-root"] != "https://git.example.test/api/packages/novox/npm/" || len(n.LeftOut) != 0 {
+		t.Fatalf("the consumer elsewhere is served the forge's public root: %v, left out %v", n.Serves, n.LeftOut)
+	}
+
+	if err := open.inventory.SetPublicDomain(ctx, "anchor", ""); err != nil {
+		t.Fatal(err)
+	}
+	plan, _, err = planFor(ctx, open, "laptop")
+	if err != nil {
+		t.Fatal(err)
+	}
+	n = need(t, plan, "lab", "npm-package-registry")
+	if _, there := n.Serves["public-root"]; there {
+		t.Fatalf("anchor composes no public name, so the key is left out: %v", n.Serves)
+	}
+	if len(n.LeftOut) != 1 || !strings.Contains(n.LeftOut[0], `without "public-root"`) {
+		t.Fatalf("and the need says so: %v", n.LeftOut)
+	}
+}