Count the long-running resources without health in a Go test over the real catalogue, through mesh-sdk's catalogue package (issue 1295, E5b)

checks/health/go.mod

@@ -0,0 +1,5 @@
+module checks/health
+
+go 1.26.0
+
+require git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261022190740-104533e8c0c9

checks/health/go.sum

@@ -0,0 +1,4 @@
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261012082113-9747f3e1b1ac h1:jnZ/n+fFMo7VQPNNXK1gjStHIJPw3SPbzPxsf/PpZqw=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261012082113-9747f3e1b1ac/go.mod h1:GFuZUElBZ9A++mxgIKo97aXXo+kV0uJ/UkbhQPPIbrY=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261022190740-104533e8c0c9 h1:Ufmd2cYEXICQ817IGflccP9bexABE4WhIO49HPbaoSo=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261022190740-104533e8c0c9/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=

checks/health/health.go

@@ -0,0 +1,70 @@
+// Package health is the catalogue's count of long-running resources that do not say how they are ready (novox/hq ADR 0240 rule
+// 8), kept in health-undeclared and judged by a test over the real tree (ADR 0529 clauses 2 and 4): it replaces the step of
+// merge-check.sh that read it out of the controller's `module check`. Every manifest is read through mesh-sdk's catalogue
+// package, the one the controller counts with.
+package health
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+	"strconv"
+	"strings"
+
+	"git.novox.be/novox/mesh-sdk/go/catalogue"
+)
+
+// Count is the long-running resources without `health` of every module under root/modules.
+func Count(root string) (int, error) {
+	manifests, err := filepath.Glob(filepath.Join(root, "modules", "*", "module.json"))
+	if err != nil {
+		return 0, err
+	}
+	sort.Strings(manifests)
+	if len(manifests) == 0 {
+		return 0, fmt.Errorf("no manifest under %s: the count would be zero for any catalogue", filepath.Join(root, "modules"))
+	}
+	n := 0
+	for _, path := range manifests {
+		m, err := catalogue.ReadTreeManifest(root, filepath.Dir(path))
+		if err != nil {
+			return 0, fmt.Errorf("%s: %w", path, err)
+		}
+		n += len(catalogue.Undeclared(m))
+	}
+	return n, nil
+}
+
+// Kept is the number the file keeps: the first number of its first line.
+func Kept(path string) (int, error) {
+	raw, err := os.ReadFile(path)
+	if err != nil {
+		return 0, err
+	}
+	first, _, _ := strings.Cut(string(raw), "\n")
+	digits := ""
+	for _, r := range strings.TrimSpace(first) {
+		if r < '0' || r > '9' {
+			break
+		}
+		digits += string(r)
+	}
+	n, err := strconv.Atoi(digits)
+	if err != nil {
+		return 0, fmt.Errorf("%s does not begin with the number it keeps: %q", path, first)
+	}
+	return n, nil
+}
+
+// Judge says what is wrong with a count against the kept number; empty when they agree. It only goes down: a rise is refused,
+// and a fall asks the new number written in health-undeclared, so the count cannot rise again.
+func Judge(kept, counted int) string {
+	switch {
+	case counted > kept:
+		return fmt.Sprintf("the long-running resources without health rose from %d to %d: declare how each new one is ready (ADR 0240 rule 8)", kept, counted)
+	case counted < kept:
+		return fmt.Sprintf("the long-running resources without health fell from %d to %d: write %d in health-undeclared, so the count cannot rise again", kept, counted, counted)
+	}
+	return ""
+}

checks/health/health_test.go

@@ -0,0 +1,88 @@
+package health
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func aCatalogue(t *testing.T, manifests map[string]string) string {
+	t.Helper()
+	root := t.TempDir()
+	for module, body := range manifests {
+		dir := filepath.Join(root, "modules", module)
+		if err := os.MkdirAll(dir, 0o755); err != nil {
+			t.Fatal(err)
+		}
+		if err := os.WriteFile(filepath.Join(dir, "module.json"), []byte(body), 0o644); err != nil {
+			t.Fatal(err)
+		}
+	}
+	return root
+}
+
+// A service that stays up and does not say how it is ready is counted; one that says, and a file, are not.
+func TestOnlyALongRunningResourceWithoutHealthIsCounted(t *testing.T) {
+	root := aCatalogue(t, map[string]string{
+		"quiet": `{"module":"quiet","resources":[{"id":"svc","type":"service","unit":"quiet.service","state":"running"}]}`,
+		"says": `{"module":"says","resources":[{"id":"svc","type":"service","unit":"says.service","state":"running",` +
+			`"health":{"kind":"unit"}}]}`,
+		"file": `{"module":"file","resources":[{"id":"cfg","type":"file","path":"/etc/file.conf","content":"x"}]}`,
+	})
+	counted, err := Count(root)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if counted != 1 {
+		t.Fatalf("counted %d, wanted the one quiet service", counted)
+	}
+}
+
+func TestTheCountMayOnlyGoDown(t *testing.T) {
+	for _, c := range []struct {
+		kept, counted int
+		says          string
+	}{
+		{58, 58, ""},
+		{58, 59, "rose from 58 to 59"},
+		{58, 57, "fell from 58 to 57"},
+	} {
+		got := Judge(c.kept, c.counted)
+		if (c.says == "") != (got == "") || !strings.Contains(got, c.says) {
+			t.Errorf("kept %d counted %d: %q, wanted %q", c.kept, c.counted, got, c.says)
+		}
+	}
+}
+
+func TestTheKeptCountIsTheFirstNumberOfTheFile(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "health-undeclared")
+	if err := os.WriteFile(path, []byte("58\nThe long-running resources ...\n"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	if n, err := Kept(path); err != nil || n != 58 {
+		t.Fatalf("%d %v", n, err)
+	}
+	if err := os.WriteFile(path, []byte("many\n"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := Kept(path); err == nil {
+		t.Fatal("a file with no number gave a count")
+	}
+}
+
+// The script's `module check` run over the real tree (novox/hq ADR 0240 rule 8, ADR 0529 clause 2 and 4): the long-running
+// resources that do not say how they are ready, counted as the controller counts them, are the number health-undeclared keeps.
+func TestTheCatalogueSaysHowItsLongRunningResourcesAreReady(t *testing.T) {
+	kept, err := Kept(filepath.Join("..", "..", "health-undeclared"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	counted, err := Count(filepath.Join("..", ".."))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if say := Judge(kept, counted); say != "" {
+		t.Fatal(say)
+	}
+}