Raise genesis on the bus the mesh runs on, from one bundle (hq issue 146, ADR 0331)

The installer could not raise a first node: the old bundle's control plane had no
MESH_BUS_NATS and crash-looped, and the NATS bundle was refused because rootsecrets
only knew the previous broker's guest:guest@ template.

One bundle now, the NATS one. rootsecrets makes the controller's bus account and puts
it in both placeholders (the address and the bcrypt hash in the carried user list),
kept with its hash so a re-run writes the same bundle. Preflight refuses a template
naming no bus connection it knows, naming the placeholder, instead of waiting out the
verify step. The broker step adopts the bus as the nats module and refuses, by name,
a catalogue without it or a server that is not the foundation's container.

internal/bootstrap/control_test.go

@@ -30,14 +30,13 @@ const theControlPlaneModule = `{
     "inventory": "/var/lib/mesh/mesh-controller/inventory",
     "identity": "/var/lib/mesh/mesh-controller/identity",
     "licences": "/var/lib/mesh/mesh-controller/licences",
-    "broker": "/var/lib/mesh/mesh-controller/broker",
-    "broker-management": "/var/lib/mesh/mesh-controller/broker-management"
+    "bus": "/var/lib/mesh/mesh-controller/bus"
   },
   "resources": [
     {"id": "mesh-state", "type": "directory", "path": "/var/lib/mesh/mesh-controller", "mode": "0700"},
     {"id": "broker-env", "type": "file", "path": "/var/lib/mesh/mesh-controller/broker.env",
      "mode": "0600",
-     "content": "MESH_BROKER_AMQP=${secret:broker}\nMESH_BROKER_MANAGEMENT=${secret:broker-management}\nMESH_BROKER_ADDRESS=${machine:at}:5671\n"},
+     "content": "MESH_BUS_NATS=${secret:bus}\nMESH_BROKER_ADDRESS=${machine:at}:5671\n"},
     {"id": "server", "type": "container", "name": "mesh-controller",
      "image": "` + builtImage + `",
      "network": "host", "args": ["serve"],
@@ -133,11 +132,10 @@ func TestTheStoreConnectionsComeFromTheBundleThatMadeThem(t *testing.T) {
 	// them at /run/secrets. Matching on the path alone would find nothing and refuse a correct
 	// manifest, which is exactly the ordinary case in the catalogue.
 	for variable, secret := range map[string]string{
-		"MESH_STORE_INVENTORY":   "inventory",
-		"MESH_STORE_IDENTITY":    "identity",
-		"MESH_STORE_LICENCES":    "licences",
-		"MESH_BROKER_AMQP":       "broker",
-		"MESH_BROKER_MANAGEMENT": "broker-management",
+		"MESH_STORE_INVENTORY": "inventory",
+		"MESH_STORE_IDENTITY":  "identity",
+		"MESH_STORE_LICENCES":  "licences",
+		"MESH_BUS_NATS":        "bus",
 	} {
 		if wanted[variable] != secret {
 			t.Errorf("%s would be accepted as %q, want %q", variable, wanted[variable], secret)
@@ -161,9 +159,10 @@ func TestTheStoreConnectionsComeFromTheBundleThatMadeThem(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	// Three stores and both halves of the broker: everything the foundation made and nothing else.
-	if len(delivered) != 5 {
-		t.Fatalf("%d values were delivered, and the foundation names five: %v",
+	// Three stores and the controller's account on the bus: everything the foundation made and
+	// nothing else.
+	if len(delivered) != 4 {
+		t.Fatalf("%d values were delivered, and the foundation names four: %v",
 			len(delivered), delivered)
 	}
 	for _, secret := range delivered {
@@ -177,12 +176,15 @@ func TestTheStoreConnectionsComeFromTheBundleThatMadeThem(t *testing.T) {
 // secret in a mesh is one the mesh made; `secret accept` is only for what predates the mesh.
 func TestASecretTheFoundationNeverMadeIsLeftToTheMesh(t *testing.T) {
 	extra := strings.Replace(theControlPlaneModule,
-		`"broker": "/var/lib/mesh/mesh-controller/broker",`,
-		`"broker": "/var/lib/mesh/mesh-controller/broker",
-    "something-new": "/var/lib/mesh/mesh-controller/something-new",`, 1)
+		`"bus": "/var/lib/mesh/mesh-controller/bus"`,
+		`"bus": "/var/lib/mesh/mesh-controller/bus",
+    "something-new": "/var/lib/mesh/mesh-controller/something-new"`, 1)
 	extra = strings.Replace(extra,
-		`"content": "MESH_BROKER_AMQP=${secret:broker}\n`,
-		`"content": "MESH_SOMETHING_NEW=${secret:something-new}\nMESH_BROKER_AMQP=${secret:broker}\n`, 1)
+		`"content": "MESH_BUS_NATS=${secret:bus}\n`,
+		`"content": "MESH_SOMETHING_NEW=${secret:something-new}\nMESH_BUS_NATS=${secret:bus}\n`, 1)
+	if extra == theControlPlaneModule {
+		t.Fatal("the fixture no longer says what this test adds to")
+	}
 
 	rewritten, err := Rewrite(theRealBundle(t), held)
 	if err != nil {