Send each resource's module and each module's build to a node that reads them; pin mesh-host at 0b391f49a25f (issue 1145)

internal/inventory/chain_source_test.go

@@ -88,16 +88,21 @@ func TestTheSourceScanFindsATablePlanted(t *testing.T) {
 	}
 }
 
-// **The last migration drops the tables of the chain, behind its guard** (issue 1096): it names each table, the column and
+// **Migration 105 drops the tables of the chain, behind its guard** (issue 1096; it was the last until issue 1145 added 106): it names each table, the column and
 // the function, drops no build_gate, and raises before it drops anything.
-func TestTheLastMigrationDropsTheTablesOfTheChain(t *testing.T) {
+func TestMigration105DropsTheTablesOfTheChain(t *testing.T) {
 	migrations, err := Migrations()
 	if err != nil {
 		t.Fatal(err)
 	}
-	last := migrations[len(migrations)-1]
-	if last.Number < 105 {
-		t.Fatalf("the last migration is %d", last.Number)
+	var last struct{ Number int }
+	for _, m := range migrations {
+		if m.Number == 105 {
+			last.Number = m.Number
+		}
+	}
+	if last.Number != 105 {
+		t.Fatal("there is no migration 105")
 	}
 	raw, err := os.ReadFile(filepath.Join("migrations", migrationFile(t, last.Number)))
 	if err != nil {

internal/inventory/migrations/0106-a-node-says-it-reads-modules.sql

@@ -0,0 +1,4 @@
+-- Whether the machine's node-engine said it reads a module on each resource of a declaration and the build of each
+-- module (its reports' `reads_modules`, novox/hq issue 1145): until it has, it is sent neither, because an older
+-- node-engine refuses a key it does not know, whole. As reads_generation (migration 0094).
+alter table node add column reads_modules boolean not null default false;

internal/inventory/sends.go

@@ -75,6 +75,21 @@ func (i *Inventory) RecordReadsGeneration(ctx context.Context, id string, reads
 	return err
 }
 
+// ReadsModules says a machine's node-engine said it reads a module per resource and a build per module (issue 1145).
+func (i *Inventory) ReadsModules(ctx context.Context, id string) (bool, error) {
+	var reads bool
+	if err := i.store.Pool().QueryRow(ctx, `select reads_modules from node where id = $1`, id).Scan(&reads); err != nil {
+		return false, fmt.Errorf("reading whether %s reads modules: %w", id, err)
+	}
+	return reads, nil
+}
+
+// RecordReadsModules keeps what a machine's latest report said of reading modules.
+func (i *Inventory) RecordReadsModules(ctx context.Context, id string, reads bool) error {
+	_, err := i.store.Pool().Exec(ctx, `update node set reads_modules = $2 where id = $1`, id, reads)
+	return err
+}
+
 // Send is one declaration sent to a machine, as the mesh records it.
 type Send struct {
 	// Node is the machine's id; NodeName its name, filled where it is read back.

internal/inventory/sends_test.go

@@ -323,3 +323,20 @@ func TestAReportIsTheLastSendsAnswerOnlyWhenItIsAboutThatSend(t *testing.T) {
 		t.Fatalf("an ordered report about sequence 21 is not its answer: %q", a)
 	}
 }
+
+// 1145/AC3: whether a machine reads modules is its latest word, as whether it reads a generation is.
+func TestWhetherAMachineReadsModulesIsItsLatestWord(t *testing.T) {
+	inv, node := aNodeWithModules(t)
+	record, err := inv.NodeByName(t.Context(), node)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, reads := range []bool{false, true, false} {
+		if err := inv.RecordReadsModules(t.Context(), record.ID, reads); err != nil {
+			t.Fatal(err)
+		}
+		if got, err := inv.ReadsModules(t.Context(), record.ID); err != nil || got != reads {
+			t.Fatalf("1145/AC3: recorded %v, read %v (%v)", reads, got, err)
+		}
+	}
+}

internal/link/enrolment.go

@@ -460,6 +460,10 @@ func (e Enrolment) Heard(ctx context.Context, report Report) (news bool, err err
 		if err := e.Inventory.RecordReadsGeneration(ctx, node.ID, report.ReadsGeneration); err != nil {
 			return false, err
 		}
+		// And whether it reads a module per resource and a build per module (novox/hq issue 1145), the same way.
+		if err := e.Inventory.RecordReadsModules(ctx, node.ID, report.ReadsModules); err != nil {
+			return false, err
+		}
 	}
 	if report.Ordered() {
 		account := AccountOf(report)

internal/link/generation_test.go

@@ -31,3 +31,18 @@ func TestTheGenerationOnTheWire(t *testing.T) {
 		t.Fatalf("a node-engine that never said it reads a generation reads as one that does: %+v", older)
 	}
 }
+
+// 1145/AC3: a report's word that the node-engine reads a module per resource and a build per module, as mesh-host's
+// report writes it: `reads_modules`, on every report of a node-engine that reads them.
+func TestWhetherTheNodeEngineReadsModulesIsOnItsReport(t *testing.T) {
+	var reads, older Report
+	if err := json.Unmarshal([]byte(`{"node":"anchor","applied":["a"],"report_sequence":8,"reads_modules":true}`), &reads); err != nil {
+		t.Fatal(err)
+	}
+	if err := json.Unmarshal([]byte(`{"node":"anchor","applied":["a"],"report_sequence":3}`), &older); err != nil {
+		t.Fatal(err)
+	}
+	if !reads.ReadsModules || older.ReadsModules {
+		t.Fatalf("1145/AC3: reads %v, an older node-engine reads %v", reads.ReadsModules, older.ReadsModules)
+	}
+}

internal/link/protocol.go

@@ -202,6 +202,10 @@ type Report struct {
 	// so, because an older node-engine refuses a key it does not know, whole. Mirrors mesh-host
 	// internal/link/messages.go.
 	ReadsGeneration bool `json:"reads_generation,omitempty"`
+	// ReadsModules says the node-engine reads a module on each resource of a declaration and the build of each module
+	// (novox/hq issue 1145), on every report it makes: the mesh sends them only to a machine that said so. Mirrors
+	// mesh-host internal/link/messages.go.
+	ReadsModules bool `json:"reads_modules,omitempty"`
 	// OlderGeneration is set on a report refusing a declaration composed from an older assignment
 	// generation than the machine applied (novox/hq issue 234). The refused declaration is the report's
 	// own Declared and Order, and its sender is read from the record of sends by that sequence.