Phase 3.1: adopt the foundation store as the postgres module

InstallStore turns the mesh-store the foundation raised at genesis into the
postgres module, adopted in place: it verifies the module's server names the
same container and the same image the foundation is running (fail-fast on a
drift, rather than tearing down the mesh's store), then registers, builds the
provisioner, and carries the superuser in via secret accept — the mesh cannot
invent a credential that already made the databases (mirroring the control
plane's store-connection delivery, control.go). pinImage generalised to any
module for reuse.

Issue 051 (WBS 3.1). One server holds the controller's contexts and every
module's database.

Claude-Session: https://claude.ai/code/session_01D6qtiYU3P9jk3pnAXyAFyx
This commit is contained in:
2026-09-16 21:04:06 +02:00
parent 121367319d
commit 9109a8c178
6 changed files with 223 additions and 16 deletions
+1 -1
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@@ -55,7 +55,7 @@
"POSTGRES_PASSWORD": "bootstrap",
"PGDATA": "/var/lib/postgresql/data/pgdata"
},
"ports": ["127.0.0.1:5432:5432"],
"ports": ["5432:5432"],
"volumes": ["mesh-store-data:/var/lib/postgresql/data"]
},
// Over TCP, not the socket. While the store initialises it runs a temporary server on the
+6 -4
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@@ -588,10 +588,12 @@ func Run(ctx context.Context, o Options, d Deps, say func(string)) (Result, erro
}
// ---- 14. store ------------------------------------------------------------------------
// A database PROVIDER. The foundation's store is the control plane's own memory and offers
// nothing to anything; the first thing that wants a database is the catalogue, next.
say("store — a database provider, which the foundation's own store is not")
if err := InstallFromCatalogue(ctx, o, permanentControl, "postgres", say); err != nil {
// The foundation's own store, ADOPTED as the `postgres` module (novox/hq issue 051): one
// server holds the control plane's contexts and every module's database, rather than the
// foundation's store beside a second one a module raised. Adopted in place — the module names
// the container the foundation is already running, and the applier leaves it be (phase3.go).
say("store — the foundation's store, adopted as the postgres module: one server, not two")
if err := InstallStore(ctx, o, permanentControl, rewritten.Declaration, say); err != nil {
return result, failed(StepStore, err)
}
+1 -1
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@@ -53,7 +53,7 @@ func InstallBuilder(ctx context.Context, o Options, d Deps, control controlPlane
"This is the manifest that makes the builder an ordinary module. Without it the mesh "+
"has the image and no way to run it, so nothing can be built here", err)
}
pinned, places, err := pinImage(manifest, published.Reference)
pinned, places, err := pinImage(manifest, published.Reference, BuilderModule)
if err != nil {
return out, err
}
+7 -7
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@@ -68,7 +68,7 @@ func InstallControlPlane(ctx context.Context, o Options, d Deps, control control
"have pivoted", err)
}
pinned, places, err := pinImage(manifest, image)
pinned, places, err := pinImage(manifest, image, ControlPlaneModule)
if err != nil {
return out, err
}
@@ -130,15 +130,15 @@ func InstallControlPlane(ctx context.Context, o Options, d Deps, control control
// carrying a real digest is one somebody pinned by hand, and quietly registering it would install a
// control plane that is not the image this machine just published — which is the one thing this
// step exists to guarantee.
func pinImage(manifest []byte, reference string) ([]byte, int, error) {
func pinImage(manifest []byte, reference, module string) ([]byte, int, error) {
places := bytes.Count(manifest, []byte(placeholderDigest))
if places == 0 {
return nil, 0, fmt.Errorf(
"the %s module's manifest carries no placeholder digest (%s), so there is nothing to "+
"pin to the image this machine just published.\n"+
"A manifest already naming a digest was pinned by somebody else, to some other "+
"build. Registering it would install a control plane that is not the one this "+
"installer carried and pushed", ControlPlaneModule, placeholderDigest)
"build. Registering it would install a module that is not the one this "+
"installer carried and pushed", module, placeholderDigest)
}
// The reference the registry gave back is `<registry>/<repository>@sha256:…`, and what the
// manifest holds is `<something>@sha256:0…0`. Replacing only the digest would leave the
@@ -157,7 +157,7 @@ func pinImage(manifest []byte, reference string) ([]byte, int, error) {
if start < 0 {
return nil, 0, fmt.Errorf(
"the %s module's manifest has a placeholder digest that is not inside a JSON "+
"string, so the installer cannot tell what image it belongs to", ControlPlaneModule)
"string, so the installer cannot tell what image it belongs to", module)
}
out.Write(rest[:start+1])
out.WriteString(reference)
@@ -170,12 +170,12 @@ func pinImage(manifest []byte, reference string) ([]byte, int, error) {
var checked map[string]any
if err := json.Unmarshal(pinned, &checked); err != nil {
return nil, 0, fmt.Errorf(
"pinning the %s module's image broke its manifest: %w", ControlPlaneModule, err)
"pinning the %s module's image broke its manifest: %w", module, err)
}
if bytes.Contains(pinned, []byte(placeholderDigest)) {
return nil, 0, fmt.Errorf(
"the %s module's manifest still carries a placeholder digest after pinning",
ControlPlaneModule)
module)
}
return pinned, places, nil
}
+3 -3
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@@ -63,7 +63,7 @@ const pushedReference = "127.0.0.1:5000/mesh-controller@sha256:" +
// with no registry in front — which a runtime would go to the internet for, and this mesh's
// control plane exists in no public registry by design.
func TestTheControlPlaneIsPinnedToWhatThisMeshsRegistryAssigned(t *testing.T) {
pinned, places, err := pinImage([]byte(theControlPlaneModule), pushedReference)
pinned, places, err := pinImage([]byte(theControlPlaneModule), pushedReference, "mesh-controller")
if err != nil {
t.Fatal(err)
}
@@ -85,7 +85,7 @@ func TestTheControlPlaneIsPinnedToWhatThisMeshsRegistryAssigned(t *testing.T) {
func TestAManifestAlreadyPinnedByHandIsRefused(t *testing.T) {
already := strings.Replace(theControlPlaneModule, placeholderDigest,
"sha256:"+strings.Repeat("9", 64), 1)
if _, _, err := pinImage([]byte(already), pushedReference); err == nil {
if _, _, err := pinImage([]byte(already), pushedReference, "mesh-controller"); err == nil {
t.Fatal("a manifest already pinned to some other image was accepted")
}
}
@@ -100,7 +100,7 @@ func TestEveryPlaceTheManifestNamesTheImageIsPinned(t *testing.T) {
{"id": "migrate", "type": "container", "name": "mesh-controller-migrate", "run-once": true,
"image": "mesh-controller@`+placeholderDigest+`", "args": ["migrate"]},`, 1)
pinned, places, err := pinImage([]byte(twice), pushedReference)
pinned, places, err := pinImage([]byte(twice), pushedReference, "mesh-controller")
if err != nil {
t.Fatal(err)
}
+205
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@@ -0,0 +1,205 @@
package bootstrap
import (
"context"
"encoding/json"
"fmt"
"strings"
"github.com/novox/mesh-host/internal/declaration"
)
// Phase three — nothing is special after installation (novox/hq issue 051).
//
// Genesis raises a store and a broker before any module system exists, because the control plane
// cannot ask provisioning for the store it keeps its own records in or the broker it is reached over
// (novox/hq ADR 0006). That leaves two servers behind: the foundation's, and a second one the
// `postgres`/`lavinmq` modules used to raise for other modules to use. This turns the foundation's
// own servers into those modules, so a mesh runs ONE postgres and ONE lavinmq — the control plane's
// contexts and every module's database in the same server (WBS 3.1/3.2).
//
// **Adopted in place, not replaced.** The control plane is stateless and is swapped for a fresh
// container (control.go); the store and broker hold the mesh's memory and its bus, so they are kept.
// The module declares a container with the same name, image and spec the foundation raised, and the
// applier — which keys on the container name and compares a spec digest (mesh-host internal/apply) —
// finds it already running and leaves it be. The image is pinned to the one the foundation is
// running, read from the bundle this installer produced, so the two specs are the same digest and
// nothing is recreated. A recreate happens only on a real upgrade, which is where a stated window
// belongs (WBS 3.3).
// StoreID and BrokerID are what the foundation bundle calls the two servers it raises; the modules
// that adopt them are found by these ids in the bundle this installer produced, the same way the
// control plane's own container is (ControlPlaneID).
const (
StoreID = "store"
BrokerID = "broker"
)
// InstallStore makes the foundation's store the `postgres` module, adopted in place.
//
// The order is InstallFromCatalogue's, with two additions the store needs and an ordinary provider
// does not: the server image is pinned to the one the foundation is already running (so the module's
// container is the same spec and is adopted, not a second one raised), and the superuser password —
// the foundation's, made at genesis — is carried in through `secret accept`, because the mesh cannot
// invent a credential that already created the databases (the same reasoning as the control plane's
// store connections, control.go deliverStores).
func InstallStore(ctx context.Context, o Options, control controlPlane,
foundation *declaration.Declaration, say func(string)) error {
const module = "postgres"
manifest, err := readManifest(o.Catalogue, module)
if err != nil {
return err
}
store, err := storeIn(foundation)
if err != nil {
return err
}
// The module adopts the running store rather than raising a second one, so its server container
// has to BE the foundation's — same name, same image. The applier keys on the name and compares
// a spec digest (internal/apply), so a mismatch here would not adopt the mesh's memory but
// replace it. Checked before anything is registered, so a drift between the two pinned upstream
// images (the catalogue's and the foundation bundle's) fails fast and by name, rather than
// surfacing as the mesh's store being torn down and recreated.
//
// Not rewritten to the foundation's: the server image travels through the builder, which reads
// the manifest from the repository and leaves a concrete image alone but would carry a rewrite
// nowhere. The two are kept equal at the source — one pinned postgres, named in both places.
if err := serverMatchesFoundation(manifest, store, module); err != nil {
return err
}
say(" adopting " + store.Name + " — the store the foundation raised, unchanged")
remote := "/" + module + "-module.json"
if err := control.carrying(ctx, module+"-module.json", manifest, remote); err != nil {
return err
}
if _, err := control.tell(ctx, "module", "add", remote); err != nil {
return err
}
say(" registered " + module)
if o.CatalogSource.Repository == "" {
return fmt.Errorf("%s has to be built and there is no --catalog-source to build it from: "+
"the catalogue CHECKOUT says what it is, the catalogue REPOSITORY is where a builder "+
"clones it", module)
}
say(" building " + module + " (the provisioner; the server is adopted, not built)")
if _, err := control.within(buildWait).tell(ctx, "build", o.CatalogSource.Repository,
"--path", "modules/"+module, "--ref", refOr(o.CatalogSource.Ref), "--wait", "1200s"); err != nil {
return err
}
if _, err := control.tell(ctx, "module", "issue", module, "--node", o.Node); err != nil {
say(" no account " + module + " — it declares nothing to say on the broker")
} else {
say(" account issued " + module)
}
if _, err := control.tell(ctx, "assign", o.Node, module); err != nil {
return err
}
// The superuser is the foundation's, made at genesis — carried in before the push, or the push
// would seal random bytes where a working password has to be and the provisioner would not open
// the store it is meant to manage.
if err := deliverSuperuser(ctx, o, control, module, store, say); err != nil {
return err
}
if _, err := pushNode(ctx, o, control, say); err != nil {
return err
}
say(" adopted mesh-store — the foundation's store is now the " + module + " module")
return nil
}
// storeIn finds the store container in the bundle this installer produced.
func storeIn(d *declaration.Declaration) (*declaration.Container, error) {
return foundationContainer(d, StoreID, "store")
}
// brokerIn finds the broker container in the bundle this installer produced.
func brokerIn(d *declaration.Declaration) (*declaration.Container, error) {
return foundationContainer(d, BrokerID, "broker")
}
func foundationContainer(d *declaration.Declaration, id, what string) (*declaration.Container, error) {
for _, r := range d.Resources {
if r.Identity() != id {
continue
}
container, ok := r.(*declaration.Container)
if !ok {
return nil, fmt.Errorf(
"this bundle's %q is a %s, not a container, so the %s module has nothing to adopt",
id, r.Kind(), what)
}
return container, nil
}
return nil, fmt.Errorf(
"this bundle names no %q, so there is no %s for a module to adopt. It declares: %s",
id, what, strings.Join(identities(d), ", "))
}
// serverMatchesFoundation checks that the module's adopting container is the one the foundation
// raised — same name, same image — so the applier reconciles it in place rather than replacing it.
func serverMatchesFoundation(manifest []byte, store *declaration.Container, module string) error {
var m struct {
Resources []struct {
Type string `json:"type"`
Name string `json:"name"`
Image string `json:"image"`
} `json:"resources"`
}
if err := json.Unmarshal(manifest, &m); err != nil {
return fmt.Errorf("the %s module's manifest is not readable: %w", module, err)
}
for _, r := range m.Resources {
if r.Type != "container" || r.Name != store.Name {
continue
}
if r.Image != store.Image {
return fmt.Errorf(
"the %s module's %q container is pinned to %q, and the foundation is running %q.\n"+
"The module adopts the foundation's store in place, so the two must name the same "+
"image — a different one would tear down the mesh's store and raise a new one on "+
"its data. Pin both to the same postgres image",
module, store.Name, r.Image, store.Image)
}
return nil
}
return fmt.Errorf(
"the %s module declares no container named %q, so it has nothing to adopt the foundation's "+
"store with. Its server container has to carry the name the foundation raised",
module, store.Name)
}
// deliverSuperuser carries the store's superuser password into the module.
//
// It is the foundation's, set on the bundle's store container at genesis; the mesh cannot invent a
// credential that already made the databases, so it goes in through `secret accept`, exactly as the
// control plane's store connections do (control.go deliverStores).
func deliverSuperuser(ctx context.Context, o Options, control controlPlane, module string,
store *declaration.Container, say func(string)) error {
const secret = "superuser"
value := strings.TrimSpace(store.Env["POSTGRES_PASSWORD"])
if value == "" {
return fmt.Errorf(
"the foundation's store names no POSTGRES_PASSWORD, so the %s module has no superuser "+
"to open it with — and the mesh cannot invent the one that already made the databases",
module)
}
at := "/accepting-" + secret
if err := control.carrying(ctx, "mesh-accepting-"+secret, []byte(value), at); err != nil {
return err
}
if _, err := control.tell(ctx, "secret", "accept", o.Node, module, secret, "--from", at); err != nil {
return err
}
say(" accepted " + secret + " — the store's superuser, as the foundation made it")
return nil
}