Write a failed publish of a merged image to the key; read mesh-build-image's captured steps (review r2)

modules/mesh-delivery-builder/internal/build/fixtures_test.go

@@ -0,0 +1,41 @@
+package build
+
+import (
+	"encoding/json"
+	"os"
+	"testing"
+
+	"git.novox.be/novox/mesh-sdk/go/delivery"
+)
+
+// result reads a captured step value of mesh-build-image (testdata/captured/README) and returns its result.
+func captured(t *testing.T, name string) json.RawMessage {
+	t.Helper()
+	raw, err := os.ReadFile("testdata/captured/" + name)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var step delivery.Step
+	if err := json.Unmarshal(raw, &step); err != nil {
+		t.Fatalf("%s: %v", name, err)
+	}
+	if step.State != delivery.StepPassed || len(step.Result) == 0 {
+		t.Fatalf("%s: state %q, result %s, want a passed step with a result", name, step.State, step.Result)
+	}
+	return step.Result
+}
+
+func TestCapturedImageStepsDecodeWithTheBuildersOwnTypes(t *testing.T) { // review r2, mesh-catalog 2; ADR 0487 clause 1
+	var f fetchResult
+	if err := json.Unmarshal(captured(t, "fetch.json"), &f); err != nil || f.Workspace == "" {
+		t.Errorf("fetch = %+v, %v, want a workspace (the field the builder reads)", f, err)
+	}
+	var trunk buildResult
+	if err := json.Unmarshal(captured(t, "build-trunk.json"), &trunk); err != nil || trunk.Digest == "" || trunk.Reference == "" {
+		t.Errorf("trunk build = %+v, %v, want a digest and a reference", trunk, err)
+	}
+	var cand buildResult
+	if err := json.Unmarshal(captured(t, "build-candidate.json"), &cand); err != nil || cand.Digest == "" || cand.Reference != "" {
+		t.Errorf("candidate build = %+v, %v, want a digest and no reference", cand, err)
+	}
+}

modules/mesh-delivery-builder/internal/build/run.go

@@ -310,6 +310,7 @@ func (b *Builder) try(ctx context.Context, module string, m delivery.Module) {
 	// built as a candidate's; the other artifacts stay as the done key has them (ADR 0487 clauses 5 and 8).
 	var prior *delivery.BuilderBuild
 	var only map[string]bool
+	publishing := false
 	if cl.Build.State == delivery.BuildDone {
 		prior, only = &cl.Build, map[string]bool{}
 		for _, bm := range OneNodeModules(cl.Build) {
@@ -317,6 +318,7 @@ func (b *Builder) try(ctx context.Context, module string, m delivery.Module) {
 		}
 		if trunk && Unpublished(cl.Build) {
 			only[ImageBuildModule] = true
+			publishing = true
 		}
 	}
 	result := b.build(ctx, module, m, plan, planErr, prior, only)
@@ -328,7 +330,11 @@ func (b *Builder) try(ctx context.Context, module string, m delivery.Module) {
 		return
 	}
 	result.By, result.Manifest = b.Claimer.By, m.Manifest
-	if cl.Build.State == delivery.BuildDone && result.State == delivery.BuildFailed && !strings.HasPrefix(result.Error, buildrun.DigestsDifferPrefix) {
+	if publishing && result.State == delivery.BuildFailed {
+		// The trunk's image was built only as a candidate's and its push failed: the key says so, so the builds view, the
+		// checker and the failed-key retake see it, and a look does not build the image again for nothing.
+		result.Error = "publishing the image of the merged commit failed: " + result.Error
+	} else if cl.Build.State == delivery.BuildDone && result.State == delivery.BuildFailed && !strings.HasPrefix(result.Error, buildrun.DigestsDifferPrefix) {
 		// A done key built again on a second node keeps its done value when the new build fails for another reason than
 		// the digests: the first build stands, and a later change of the nodes looks again.
 		b.logf("%s: built again on a second node and failed, the done build stands: %s", cl.Key, result.Error)
@@ -597,6 +603,18 @@ func (b *Builder) step(ctx context.Context, bm, node, tool string, args map[stri
 	return b.Runner.Run(ctx, bm, node, toolPrefix[bm]+tool, args)
 }
 
+// fetchResult and buildResult are the results of a build module's fetch and build steps as the builder reads them.
+type fetchResult struct {
+	Workspace string   `json:"workspace"`
+	Merge     string   `json:"merge"`
+	Conflicts []string `json:"conflicts"`
+}
+
+type buildResult struct {
+	Digest    string `json:"digest"`
+	Reference string `json:"reference"`
+}
+
 // runLane takes a place on the node, fetches the commit there and builds each of the lane's artifacts, one step at a time.
 func (b *Builder) runLane(ctx context.Context, l *lane, repository string, m delivery.Module, module string) {
 	release, err := b.Places.Acquire(ctx, l.node)
@@ -619,11 +637,7 @@ func (b *Builder) runLane(ctx context.Context, l *lane, repository string, m del
 		l.err = err
 		return
 	}
-	var fetched struct {
+	var fetched fetchResult
-		Workspace string   `json:"workspace"`
-		Merge     string   `json:"merge"`
-		Conflicts []string `json:"conflicts"`
-	}
 	if err := json.Unmarshal(raw, &fetched); err != nil || fetched.Workspace == "" {
 		l.err = fmt.Errorf("the fetch on %s answered no workspace: %s", l.node, raw)
 		return
@@ -652,10 +666,7 @@ func (b *Builder) runLane(ctx context.Context, l *lane, repository string, m del
 			l.err = err
 			return
 		}
-		var built struct {
+		var built buildResult
-			Digest    string `json:"digest"`
-			Reference string `json:"reference"`
-		}
 		if err := json.Unmarshal(raw, &built); err != nil || built.Digest == "" {
 			l.err = fmt.Errorf("the build of %s of %s on %s answered no digest: %s", t.Artifact, module, l.node, raw)
 			return

modules/mesh-delivery-builder/internal/build/run_test.go

@@ -606,3 +606,28 @@ func TestASecondGoNodeDoesNotBuildOrPushTheImageAgain(t *testing.T) { // review
 		t.Errorf("%d go builds, want 3", n)
 	}
 }
+
+func TestAFailedPublishOfACandidatesImageIsWrittenToTheKey(t *testing.T) { // review r2, mesh-delivery 1; ADR 0487 clause 5
+	r := newRig(t, imageArt)
+	r.b.Health = imageHave(t, "ace")
+	trunkModule(t, r)
+	r.b.Candidate(context.Background(), "feat%2Fx", candidateValue(t, "feat/x", 7, headX))
+	r.b.Wait()
+	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildDone {
+		t.Fatalf("candidate build = %+v", v)
+	}
+	r.bm.fails["ace/build_image_build"] = "push to the registry: connection refused"
+	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m")) // the merge: the trunk names the fingerprint
+	r.b.Wait()
+	v := valueOf(t, r.st, r.key)
+	if v.State != delivery.BuildFailed || !strings.Contains(v.Error, "connection refused") || !strings.Contains(v.Error, "publish") {
+		t.Fatalf("build = %+v, want failed naming the publish and its reason", v)
+	}
+	// The failed key is retaken as any failed key is, and ends published once the registry answers.
+	delete(r.bm.fails, "ace/build_image_build")
+	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
+	r.b.Wait()
+	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildDone || v.Artifacts[0].Reference == "" {
+		t.Errorf("build = %+v, want done with a reference", v)
+	}
+}

modules/mesh-delivery-builder/internal/build/testdata/captured/README

@@ -0,0 +1,4 @@
+Captured step values of mesh-build-image (fetch, a candidate's build, a trunk's build), copied from
+novox/mesh-catalog modules/mesh-build-image/cmd/mesh-build-image/testdata/captured/. Both copies must change together: the
+module's capture test writes them, and the builder's TestCapturedImageStepsDecodeWithTheBuildersOwnTypes (internal/build,
+fixtures_test.go) decodes these with the types the builder reads results with and fails on a missing field.

modules/mesh-delivery-builder/internal/build/testdata/captured/build-candidate.json

@@ -0,0 +1,14 @@
+{
+  "ended": "2026-10-22T08:00:01Z",
+  "id": "STEPID",
+  "node": "ace",
+  "result": {
+    "artifact": "server",
+    "digest": "sha256:1111111111111111111111111111111111111111111111111111111111111111",
+    "pushed": false
+  },
+  "started": "2026-10-22T08:00:00Z",
+  "state": "passed",
+  "tool": "build_image_build",
+  "v": 1
+}

modules/mesh-delivery-builder/internal/build/testdata/captured/build-trunk.json

@@ -0,0 +1,15 @@
+{
+  "ended": "2026-10-22T08:00:01Z",
+  "id": "STEPID",
+  "node": "ace",
+  "result": {
+    "artifact": "server",
+    "digest": "sha256:1111111111111111111111111111111111111111111111111111111111111111",
+    "pushed": true,
+    "reference": "REGISTRY/fixture-image/server@sha256:1111111111111111111111111111111111111111111111111111111111111111"
+  },
+  "started": "2026-10-22T08:00:00Z",
+  "state": "passed",
+  "tool": "build_image_build",
+  "v": 1
+}

modules/mesh-delivery-builder/internal/build/testdata/captured/fetch.json

@@ -0,0 +1,13 @@
+{
+  "ended": "2026-10-22T08:00:01Z",
+  "id": "STEPID",
+  "node": "ace",
+  "result": {
+    "commit": "COMMIT",
+    "workspace": "WORKSPACE"
+  },
+  "started": "2026-10-22T08:00:00Z",
+  "state": "passed",
+  "tool": "build_image_fetch",
+  "v": 1
+}