CAT-RD1: artifact-store-tools asks the assigner's wants and the indexer's manifests once and follows their events, no reads

modules/artifact-store-tools/cmd/artifact-store-tools/door.go

@@ -8,10 +8,13 @@ import (
 	"fmt"
 	"os"
 	"strings"
+	"sync/atomic"
 	"time"
 
 	stdio "git.novox.be/novox/mesh-sdk/go"
 
+	"git.novox.be/novox/mesh-delivery/sdk/views"
+
 	"artifactstoretools/internal/registry"
 )
 
@@ -53,10 +56,22 @@ func DoorAt(file string) func() (Door, error) {
 }
 
 // runtimeBus is the holder's bus through the runtime: its reads, its findings and its seat's event.
-type runtimeBus struct{}
+type runtimeBus struct{ views *views.Reader }
 
-func (runtimeBus) Keys(state string) ([]string, error) { return stdio.State(state).Keys() }
-func (runtimeBus) Get(state, key string) ([]byte, bool, error) {
+// followed says whether the state is the indexer's or the assigner's, which the holder asks once and follows by events
+// (ADR 0615) rather than reads.
+func (b runtimeBus) followed(state string) bool { return b.views != nil && b.views.Follows(state) }
+
+func (b runtimeBus) Keys(state string) ([]string, error) {
+	if b.followed(state) {
+		return b.views.Keys(state)
+	}
+	return stdio.State(state).Keys()
+}
+func (b runtimeBus) Get(state, key string) ([]byte, bool, error) {
+	if b.followed(state) {
+		return b.views.Get(state, key)
+	}
 	e, err := stdio.State(state).Get(key)
 	if err != nil || e == nil {
 		return nil, false, err
@@ -90,7 +105,7 @@ func (runtimeBus) Publish(subject string, body any) error {
 
 // follow watches the builder's done keys and the wants: a build's end sweeps and
 // observes again; a want changed observes again. Event-driven: nothing reads them on a timer.
-func follow(h *Holder) {
+func follow(h *Holder, v *views.Reader) {
 	<-stdio.Served()
 	watch := func(state string, handle func(stdio.StateChange) error) {
 		for {
@@ -119,11 +134,22 @@ func follow(h *Holder) {
 		}
 		return nil
 	})
-	watch(WantsRead, func(c stdio.StateChange) error {
-		if !c.Current {
-			go observe()
+	// The wants are the assigner's: the first view then its events (ADR 0615). What Watch hands over before it returns
+	// is the first view, not a change.
+	var current atomic.Bool
+	current.Store(true)
+	for {
+		err := v.Watch(WantsRead, func(string, []byte, bool) {
+			if !current.Load() {
+				go observe()
+			}
+		})
+		if err == nil {
+			break
 		}
-		return nil
-	})
+		h.logf("watching %s: %v; asked again in 10s", WantsRead, err)
+		time.Sleep(10 * time.Second)
+	}
+	current.Store(false)
 	observe()
 }

modules/artifact-store-tools/cmd/artifact-store-tools/holder.go

@@ -29,6 +29,8 @@ import (
 	"git.novox.be/novox/mesh-sdk/go/handacts"
 	"git.novox.be/novox/mesh-sdk/go/health"
 
+	"git.novox.be/novox/mesh-delivery/sdk/views"
+
 	"artifactstoretools/internal/registry"
 )
 
@@ -900,6 +902,12 @@ func (h *Holder) Observe(ctx context.Context) error {
 	}
 	for _, k := range keys {
 		if _, still := now[k]; !still {
+			// A finding of a first view unanswered is the reader's (views.Reader), cleared by its answer, not by a sweep.
+			if raw, found, err := h.Bus.Get(FindingsState, k); err == nil && found {
+				if f, err := health.DecodeFinding(raw); err == nil && f.Kind == views.UnansweredKind {
+					continue
+				}
+			}
 			if err := h.Bus.Delete(FindingsState, k); err != nil {
 				return err
 			}

modules/artifact-store-tools/cmd/artifact-store-tools/main.go

@@ -10,12 +10,17 @@
 package main
 
 import (
+	"context"
+	"encoding/json"
 	"fmt"
 	"os"
 	"time"
 
 	stdio "git.novox.be/novox/mesh-sdk/go"
+	"git.novox.be/novox/mesh-sdk/go/delivery"
 	"git.novox.be/novox/mesh-sdk/go/handacts"
+
+	"git.novox.be/novox/mesh-delivery/sdk/views"
 )
 
 func logf(format string, a ...any) { fmt.Fprintf(os.Stderr, format+"\n", a...) }
@@ -26,13 +31,32 @@ func main() {
 		Run:       ExecRunner,
 		UID:       os.Getuid(),
 	}
-	h := &Holder{Bus: runtimeBus{}, Door: DoorAt(os.Getenv("MESH_ARTIFACT_STORE_ADDRESS_FILE")), Listed: s.View,
+	v := &views.Reader{Module: "artifact-store-tools", Logf: logf, Findings: viewFindings{}}
+	v.Follow(delivery.AssignerModule, "wants", WantsTool)
+	v.Follow(delivery.IndexerModule, "manifests", ManifestsTool)
+	h := &Holder{Bus: runtimeBus{views: v}, Door: DoorAt(os.Getenv("MESH_ARTIFACT_STORE_ADDRESS_FILE")), Listed: s.View,
 		Now: time.Now, Logf: logf}
 	h.Acts = handacts.Recorder{Ask: stdio.Ask}
-	go follow(h)
+	v.Start(context.Background())
+	go follow(h, v)
 	// An empty name serves as the module the runtime names (MESH_SERVED_MODULE): artifact-store-tools.
-	if err := stdio.Serve("", append(Tools(s, h, &Catalogue{Ask: stdio.Ask}), SeatTools(h, s)...)); err != nil {
+	if err := stdio.Serve("", append(append(Tools(s, h, &Catalogue{Ask: stdio.Ask}), SeatTools(h, s)...), v.Tools("artifact_store")...)); err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}
 }
+
+// The owners' read tools of the states the holder follows, which the manifest invokes (ADR 0615).
+const (
+	WantsTool     = delivery.AssignerModule + ".assigner_read_wants"
+	ManifestsTool = delivery.IndexerModule + ".indexer_read_manifests"
+)
+
+// viewFindings writes the holder's finding of a first view unanswered into its own state findings.
+type viewFindings struct{}
+
+func (viewFindings) Put(key string, value []byte) error {
+	_, err := stdio.State(FindingsState).Put(key, json.RawMessage(value))
+	return err
+}
+func (viewFindings) Delete(key string) error { return stdio.State(FindingsState).Delete(key) }

modules/artifact-store-tools/cmd/artifact-store-tools/store_test.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"git.novox.be/novox/mesh-delivery/sdk/views"
 	"git.novox.be/novox/mesh-sdk/go/catalogue"
 
 	"context"
@@ -8,6 +9,7 @@ import (
 	"fmt"
 	"os"
 	"reflect"
+	"slices"
 	"sort"
 	"strconv"
 	"strings"
@@ -443,10 +445,11 @@ func TestTheToolsServedAreTheToolsTheManifestNames(t *testing.T) {
 		t.Fatal(err)
 	}
 	var m struct {
-		Tools   []string `json:"tools"`
-		Invokes []string `json:"invokes"`
-		Reads   []string `json:"reads"`
-		Claims  []struct {
+		Tools    []string `json:"tools"`
+		Invokes  []string `json:"invokes"`
+		Reads    []string `json:"reads"`
+		Consumes []string `json:"consumes"`
+		Claims   []struct {
 			Name   string   `json:"name"`
 			Serves []string `json:"serves"`
 		} `json:"claims"`
@@ -455,7 +458,7 @@ func TestTheToolsServedAreTheToolsTheManifestNames(t *testing.T) {
 		t.Fatal(err)
 	}
 	var served []string
-	for _, tl := range Tools(&Store{}, recordsAsked{&asked{}}, &Catalogue{}) {
+	for _, tl := range append(Tools(&Store{}, recordsAsked{&asked{}}, &Catalogue{}), (&views.Reader{}).Tools("artifact_store")...) {
 		if !strings.HasPrefix(tl.Name, "artifact_store_") || tl.Description == "" || tl.Run == nil {
 			t.Errorf("tool %q", tl.Name)
 		}
@@ -469,10 +472,15 @@ func TestTheToolsServedAreTheToolsTheManifestNames(t *testing.T) {
 	}
 	// ADR 0571 clause 2: it holds the seat mesh-artifact-sweep and serves its verbs, and calls no verb of the controller's;
 	// it reads no controller state, the lease neither (issue 1126).
-	want := []string{"seat:mesh-hand-acts.hand-act", CatalogueModules, CatalogueModule}
+	want := []string{"seat:mesh-hand-acts.hand-act", CatalogueModules, CatalogueModule, WantsTool, ManifestsTool}
 	if !reflect.DeepEqual(m.Invokes, want) {
 		t.Errorf("invokes %v", m.Invokes)
 	}
+	// ADR 0615: the assigner's wants and the indexer's manifests are asked once and followed by their events, not read.
+	if !reflect.DeepEqual(m.Consumes, []string{"mesh-delivery-assigner.views.wants", "mesh-delivery-indexer.views.manifests"}) ||
+		slices.Contains(m.Reads, WantsRead) || slices.Contains(m.Reads, ManifestsRead) {
+		t.Errorf("consumes %v, reads %v", m.Consumes, m.Reads)
+	}
 	var verbs []string
 	for _, tl := range SeatTools(&Holder{}, &Store{}) {
 		verbs = append(verbs, strings.TrimPrefix(tl.Name, catalogue.ArtifactSweepSeat+"."))

modules/artifact-store-tools/module.json

@@ -20,15 +20,19 @@
   "invokes": [
     "seat:mesh-hand-acts.hand-act",
     "seat:mesh-catalog.modules",
-    "seat:mesh-catalog.module"
+    "seat:mesh-catalog.module",
+    "mesh-delivery-assigner.assigner_read_wants",
+    "mesh-delivery-indexer.indexer_read_manifests"
   ],
   "reads": [
-    "mesh-delivery-assigner.wants",
     "mesh-delivery-builder.builds",
     "mesh-delivery-builder.build-log",
-    "mesh-delivery-indexer.manifests",
     "node-engine.have"
   ],
+  "consumes": [
+    "mesh-delivery-assigner.views.wants",
+    "mesh-delivery-indexer.views.manifests"
+  ],
   "state": [
     "findings"
   ],
@@ -36,7 +40,9 @@
     "artifact_store_repositories",
     "artifact_store_usage",
     "artifact_store_references",
-    "artifact_store_collect"
+    "artifact_store_collect",
+    "artifact_store_first_views",
+    "artifact_store_first_view_again"
   ],
   "config": {
     "older-store-names": {