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

cmd/mesh-controller/sendable.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"sort"
 	"strings"
 
@@ -38,6 +39,13 @@ type sendable struct {
 	// the send; never on the wire.
 	composedFrom int64
 	actingEpoch  uint64
+	// ReadsModules says the machine's node-engine reads a module per resource and a build per module (novox/hq issue
+	// 1145): only then are they sent, because an older node-engine refuses a key it does not know, whole.
+	ReadsModules bool
+	// moduleOf is the composer's owner of each resource id, and buildIDs the build each module carries (its id):
+	// kept beside the resources, and on the wire only to a machine that reads them.
+	moduleOf map[string]string
+	buildIDs map[string]string
 	// modules are the modules this declaration names, for the record of the send; never on the wire.
 	modules []string
 	// localNetwork is every port admitted from the local network and what it resolved to (novox/hq ADR
@@ -111,6 +119,28 @@ type adoptionEnvelope struct {
 // Body is the declaration's bytes, as sent and as digested.
 func (s sendable) Body() ([]byte, error) {
 	envelope := map[string]any{"declaration": 1, "resources": s.Resources}
+	if s.ReadsModules {
+		// The module of each resource the composer owns (what the mesh adds of its own has none), and the build of each
+		// module (novox/hq issue 1145): to a machine that said it reads them, and no other.
+		named := make([]map[string]any, len(s.Resources))
+		for n, r := range s.Resources {
+			module, owned := s.moduleOf[fmt.Sprint(r["id"])]
+			if !owned {
+				named[n] = r
+				continue
+			}
+			with := make(map[string]any, len(r)+1)
+			for k, v := range r {
+				with[k] = v
+			}
+			with["module"] = module
+			named[n] = with
+		}
+		envelope["resources"] = named
+		if len(s.buildIDs) > 0 {
+			envelope["builds"] = s.buildIDs
+		}
+	}
 	if s.Adoption != nil {
 		envelope["adoption"] = s.Adoption
 	}