Review round 1 for the Node build module: registry for other @novox packages and refused bundles (1489), toolchain.reported stream (1483, 1488), re-pin to mesh-sdk 36d6f774; delta part 4 of 4

modules/mesh-build-node/cmd/mesh-build-node/module.go

@@ -36,6 +36,9 @@ type Module struct {
 	Clock func() time.Time
 	// Toolchains and Steps are the Put of the states of those names.
 	Toolchains, Steps buildstep.Put
+	// Emit tells the bus an event (stdio.Emit); nil emits nothing. The guard emits toolchain.reported after each write of
+	// the toolchains key, so the indexer, which holds no timer, learns that the bucket exists (issue 1444).
+	Emit func(eventType string, body any) error
 	// Ctx is the process's context, which a step runs under (the tool call's is cut at 30 s, the step's is not).
 	Ctx context.Context
 	Say func(format string, a ...any)
@@ -51,7 +54,7 @@ func (m *Module) recipe() Recipe {
 }
 
 func (m *Module) guard(r Recipe) buildstep.Guard {
-	return buildstep.Guard{Language: "typescript", Want: r.Node, Recipe: r.Version(), Probe: m.Probe, Node: m.Node, Put: m.Toolchains}
+	return buildstep.Guard{Language: "typescript", Want: r.Node, Recipe: r.Version(), Probe: m.Probe, Node: m.Node, Put: m.reportingPut()}
 }
 
 // Check reads the installed toolchain, writes <node>.typescript of the toolchains state and answers nil, or the
@@ -176,3 +179,21 @@ func pathOrDefault() string {
 	}
 	return defaultPath
 }
+
+// ToolchainReported is the event the guard emits after it writes the toolchains key.
+const ToolchainReported = "toolchain.reported"
+
+// reportingPut is the toolchains Put that then emits toolchain.reported with the node and the language. A write that
+// failed emits nothing; an emit that failed is said and does not refuse the step.
+func (m *Module) reportingPut() buildstep.Put {
+	return func(key string, value any) (uint64, error) {
+		rev, err := m.Toolchains(key, value)
+		if err != nil || m.Emit == nil {
+			return rev, err
+		}
+		if eerr := m.Emit(ToolchainReported, map[string]string{"node": m.Node, "language": "typescript"}); eerr != nil && m.Say != nil {
+			m.Say("the event %s could not be emitted: %v", ToolchainReported, eerr)
+		}
+		return rev, nil
+	}
+}