feat: centralize Barkfile schema

watch_test.go

@@ -0,0 +1,75 @@
+package barkfile
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+func TestWatchDeliversInitialAndChangedConfiguration(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "Barkfile")
+	writeWatchConfig(t, path, ":5432")
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	changes, err := Watch(ctx, path, WatchOptions{PollInterval: 10 * time.Millisecond})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if change := nextChange(t, changes); change.Err != nil || change.Config.Listen != ":5432" {
+		t.Fatalf("initial change = %#v", change)
+	}
+
+	writeWatchConfig(t, path, ":6543")
+	if change := nextChange(t, changes); change.Err != nil || change.Config.Listen != ":6543" {
+		t.Fatalf("changed configuration = %#v", change)
+	}
+}
+
+func TestWatchReportsInvalidRevisionAndRecovers(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "Barkfile")
+	writeWatchConfig(t, path, ":5432")
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	changes, err := Watch(ctx, path, WatchOptions{PollInterval: 10 * time.Millisecond})
+	if err != nil {
+		t.Fatal(err)
+	}
+	_ = nextChange(t, changes)
+	if err := os.WriteFile(path, []byte("pawsql {\n listen :5432\n}"), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	if change := nextChange(t, changes); change.Err == nil {
+		t.Fatal("invalid revision did not report an error")
+	}
+
+	writeWatchConfig(t, path, ":7654")
+	if change := nextChange(t, changes); change.Err != nil || change.Config.Listen != ":7654" {
+		t.Fatalf("recovered configuration = %#v", change)
+	}
+}
+
+func nextChange(t *testing.T, changes <-chan Change) Change {
+	t.Helper()
+	select {
+	case change, open := <-changes:
+		if !open {
+			t.Fatal("watch channel closed before delivering a change")
+		}
+		return change
+	case <-time.After(time.Second):
+		t.Fatal("timed out waiting for Barkfile change")
+		return Change{}
+	}
+}
+
+func writeWatchConfig(t *testing.T, path, listen string) {
+	t.Helper()
+	contents := "pawsql {\n listen " + listen + "\n tls {\n  cert cert.pem\n  key key.pem\n }\n database app {\n  upstream 127.0.0.1:5432\n }\n}\n"
+	if err := os.WriteFile(path, []byte(contents), 0o600); err != nil {
+		t.Fatal(err)
+	}
+}