Merge pull request 'The seat calls a gate that raised no machine the mesh composes an error, whatever judged it (hq issue 285)' (#106) from fix/seat-refuses-a-gate-that-raised-nothing into main

internal/builder/check.go

@@ -298,6 +298,13 @@ func Check(ctx context.Context, run Runner, spec CheckSpec, workspace, registry
 	say("check", "the facts of %s (%s): %d machine(s), the bus at %s, the store at %s", f.Taken.Format(time.RFC3339),
 		short(strings.TrimPrefix(digest, "sha256:")), len(f.Machines), f.Versions.Bus, f.Versions.Store)
 
+	// **What an earlier delivery of this same ask left is removed first** (novox/hq issue 285): an ask is
+	// redelivered when the holder that took it stopped mid-check — the build agent itself updated by the
+	// rollout it is checking — and its containers, named by the ask's id, are still there. Raising the
+	// store again under that name was refused, and the check said it could not run.
+	if n, err := RemoveContainersOf(ctx, run, spec.ID); err == nil && n > 0 {
+		say("check", "removed %d throwaway container(s) an earlier delivery of this check left", n)
+	}
 	// The throwaway store and bus, of the versions the mesh runs, removed whatever happens.
 	defer func() {
 		removing, done := context.WithTimeout(context.Background(), time.Minute)
@@ -526,14 +533,17 @@ func gateLayer(ctx context.Context, spec CheckSpec, tree, root, gate, verdictFil
 		// The gate could not judge: not the change's fault, and never a pass.
 		return "error", "the merge gate could not judge the change: " + lastLine(out.String())
 	}
-	var said struct {
-		Verdict string `json:"verdict"`
-		Summary string `json:"summary"`
-	}
 	raw, err := os.ReadFile(verdictFile)
-	if err != nil || json.Unmarshal(raw, &said) != nil || said.Verdict == "" {
+	if err != nil {
 		return "error", "the merge gate said no verdict"
 	}
+	said, ok := readGateVerdict(raw)
+	if !ok {
+		return "error", "the merge gate said no verdict"
+	}
+	if verdict, summary, raised := gateRaisedTheMesh(said); !raised {
+		return verdict, summary
+	}
 
 	// 3. **The replays of what the mesh runs** (to-be 45 §9, M9): mesh-lab's, from its main — reviewed code,
 	// so given the container runtime the resolver replay raises containers with — against the bus of the
@@ -683,6 +693,58 @@ func newProblems(change, base string) []string {
 	return out
 }
 
+// gateVerdict is what of the gate's verdict the seat reads: the verdict, and every machine — whether it
+// composes on the mesh and whether it composed in the gate's store without the change.
+type gateVerdict struct {
+	Verdict  string `json:"verdict"`
+	Summary  string `json:"summary"`
+	Machines []struct {
+		Described string `json:"described"`
+		Live      bool   `json:"live-composes"`
+		Base      struct {
+			Composes bool `json:"composes"`
+		} `json:"base"`
+	} `json:"machines"`
+}
+
+// readGateVerdict reads the verdict the gate wrote, from its first line that opens a JSON document: a
+// judge from before the verdict was alone on its output printed what composition said ahead of it.
+func readGateVerdict(raw []byte) (gateVerdict, bool) {
+	var v gateVerdict
+	text := string(raw)
+	if i := strings.Index(text, "\n{"); i >= 0 && !strings.HasPrefix(strings.TrimSpace(text), "{") {
+		text = text[i+1:]
+	}
+	if json.Unmarshal([]byte(text), &v) != nil || v.Verdict == "" {
+		return gateVerdict{}, false
+	}
+	return v, true
+}
+
+// gateRaisedTheMesh is the seat's own reading of a verdict that passes (novox/hq issue 285): **a machine
+// the mesh composes that did not compose in the gate's store without the change makes the gate an error,
+// never a pass** — the change was judged against a machine that is not the mesh's, broken against broken.
+// The judge says so itself since issue 285, but the judge is the controller the mesh runs, and one from
+// before it passed such a verdict; read here too, the rule holds whatever judged. It answers false, with
+// the verdict to report, when the gate did not raise the mesh.
+func gateRaisedTheMesh(v gateVerdict) (string, string, bool) {
+	if v.Verdict != "pass" && v.Verdict != "warning" {
+		return "", "", true
+	}
+	var unraised []string
+	for _, m := range v.Machines {
+		if m.Live && !m.Base.Composes {
+			unraised = append(unraised, m.Described)
+		}
+	}
+	if len(unraised) == 0 {
+		return "", "", true
+	}
+	return "error", fmt.Sprintf("the mesh as it is could not be raised, so the change cannot be judged against it: "+
+		"%d of %d machines compose on the mesh and not in the gate (the first: %s) — novox/hq issue 285",
+		len(unraised), len(v.Machines), unraised[0]), false
+}
+
 // gitShow is a file as a ref has it.
 func gitShow(ctx context.Context, dir, ref, file string) ([]byte, error) {
 	cmd := exec.CommandContext(ctx, "git", "show", ref+":"+filepath.ToSlash(file))

internal/builder/check_test.go

@@ -429,3 +429,54 @@ func TestAFailedScriptIsSaidByWhatFailed(t *testing.T) {
 		}
 	}
 }
+
+// **Issue 285**: a judge from before the rule passed "every machine composes with the change as it did
+// without (0 of 4 compose)". The seat reads the machines itself: a machine the mesh composes that did not
+// compose in the gate's store makes the gate an error, whatever judged it.
+func TestTheSeatCallsAGateThatRaisedNoMachineAnError(t *testing.T) {
+	old := "bus users without a credential: controller\n" + `{"verdict":"pass","summary":"every machine composes with the change as it did without (0 of 2 compose)",
+		"machines":[{"described":"the hub","live-composes":true,"base":{"composes":false}},
+		{"described":"a machine","live-composes":true,"base":{"composes":false}}]}`
+	v, ok := readGateVerdict([]byte(old))
+	if !ok {
+		t.Fatal("a verdict after a line of composition's was not read")
+	}
+	verdict, summary, raised := gateRaisedTheMesh(v)
+	if raised || verdict != "error" || !strings.Contains(summary, "2 of 2 machines") || !strings.Contains(summary, "the hub") {
+		t.Errorf("0 of 2 composing is %q %q", verdict, summary)
+	}
+	good := `{"verdict":"pass","summary":"(2 of 2 compose)","machines":[{"described":"the hub","live-composes":true,"base":{"composes":true}},
+		{"described":"a laptop","live-composes":false,"base":{"composes":false}}]}`
+	v, _ = readGateVerdict([]byte(good))
+	if _, _, raised := gateRaisedTheMesh(v); !raised {
+		t.Error("a machine that does not compose on the mesh either was read as the gate's failure")
+	}
+	failed := `{"verdict":"fail","summary":"x","machines":[{"described":"the hub","live-composes":true,"base":{"composes":false}}]}`
+	v, _ = readGateVerdict([]byte(failed))
+	if _, _, raised := gateRaisedTheMesh(v); !raised {
+		t.Error("a failing verdict is the change's, and stands")
+	}
+}
+
+// **Issue 285**: an ask redelivered after its holder stopped mid-check found its own throwaway store still
+// there under its name, and the check said it could not run. What an earlier delivery left goes first.
+func TestARedeliveredCheckRemovesWhatItsEarlierDeliveryLeft(t *testing.T) {
+	registry := checkEnvironment(t)
+	repo, head := aCheckedRepository(t, map[string]string{CheckScript: "echo checked\n"})
+	id := fmt.Sprintf("check-again-%d", time.Now().UnixNano())
+	if out, err := exec.Command("docker", "run", "-d", "--rm", "--label", BuildLabel+"="+id, "--name", id+"-store",
+		"postgres:17-alpine", "sleep", "300").CombinedOutput(); err != nil {
+		t.Skipf("no container for the earlier delivery: %v %s", err, out)
+	}
+	v, err := Check(t.Context(), Command, CheckSpec{ID: id, Repository: repo, Ref: head, Owner: "novox",
+		Repo: "hq", Number: 7, Toolchain: goToolchain}, t.TempDir(), registry, GitCredential{}, nil)
+	if err != nil {
+		t.Fatalf("a redelivered check could not run: %v", err)
+	}
+	if v.Repo == nil || v.Repo.Verdict != "pass" {
+		t.Errorf("the repository's check answered %+v", v.Repo)
+	}
+	if left := labelled(id); len(left) > 0 {
+		t.Errorf("the check left %d container(s) behind", len(left))
+	}
+}