fix: address code review findings

- Fix notifications_sent PK: changed from (rgid, sent_at) to rgid-only PK
  to prevent duplicate RGID rows across seconds. Use INSERT OR REPLACE
  instead of INSERT OR IGNORE for true idempotency.
- Add foreign key constraints to DDL (artist_id references artist_settings,
  rgid references external_releases) per specification.
- Enable PRAGMA foreign_keys=ON and PRAGMA busy_timeout=5000 for concurrent
  access safety.
- Fix GetNotificationSentAt query: add ORDER BY sent_at DESC LIMIT 1 for
  deterministic results.
- Fix config test: change YAML key from 'chat' to 'chat_id' to match struct
  tag, add ChatID assertion.
- Fix migration tracking test: correct error message from "expected 4" to
  "expected 3".
- Remove dead code in TestLoadConfig_InvalidPort: eliminate unused YAML
  template and remove port 0 case (valid, not invalid).
- Remove unused path parameter from buildConfigWithPort helper.
- Remove pointless 100ms sleep in run() and unused time import.
- Remove tautological TestDefaultConfigPath test.
- Update README.md: Go version 1.21+ to 1.25+, placeholder passwords to
  CHANGE_ME.
- Update config.yaml.example: placeholder passwords to CHANGE_ME.
- Update all database tests to insert parent rows first for FK satisfaction.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

README.md

@@ -28,7 +28,7 @@ NaviWatcher is an autonomous service daemon that monitors your Navidrome music c
 
 ### Technology Stack
 
-- **Language:** Go 1.21+
+- **Language:** Go 1.25+
 - **Database:** SQLite 3
 - **HTTP Server:** Go standard library (`net/http` + `html/template`)
 - **Key dependencies:**
@@ -69,12 +69,12 @@ server:
   host: "0.0.0.0"
   port: 8080
   username: "admin"
-  password: "password123"
+  password: "CHANGE_ME"
 
 navidrome:
   url: "http://localhost:4533"
   user: "watcher_service"
-  password: "user_password"
+  password: "CHANGE_ME"
 
 musicbrainz:
   user_agent: "NaviWatcher/1.0 ( mail@example.com )"
@@ -176,12 +176,12 @@ server:
   host: "0.0.0.0"
   port: 8080
   username: "admin"
-  password: "password123"
+  password: "CHANGE_ME"
 
 navidrome:
   url: "http://localhost:4533"
   user: "watcher_service"
-  password: "user_password"
+  password: "CHANGE_ME"
 
 musicbrainz:
   user_agent: "NaviWatcher/1.0 ( mail@example.com )"

cmd/naviwatcher/main.go

@@ -7,7 +7,6 @@ import (
 	"os"
 	"os/signal"
 	"syscall"
-	"time"
 
 	"naviwatcher/internal/config"
 )
@@ -51,7 +50,5 @@ func run(ctx context.Context, cfg *config.Config) error {
 	// Business logic will be added in future tasks.
 	<-ctx.Done()
 
-	// Graceful shutdown delay to let goroutines finish.
-	time.Sleep(100 * time.Millisecond)
 	return nil
 }

cmd/naviwatcher/main_test.go

@@ -9,12 +9,6 @@ import (
 	"naviwatcher/internal/config"
 )
 
-func TestDefaultConfigPath(t *testing.T) {
-	if defaultConfigPath != "config.yaml" {
-		t.Errorf("expected default config path 'config.yaml', got %q", defaultConfigPath)
-	}
-}
-
 func TestRun_GracefulShutdown(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	cancel()

config.yaml.example

@@ -3,12 +3,12 @@ server:
   port: 8080
   # Basic Auth for Web UI access
   username: "admin"
-  password: "password123"
+  password: "CHANGE_ME"
 
 navidrome:
   url: "http://localhost:4533"
   user: "watcher_service"
-  password: "user_password"
+  password: "CHANGE_ME"
 
 musicbrainz:
   user_agent: "NaviWatcher/1.0 ( your-email@example.com )"

coverage.out

@@ -0,0 +1,139 @@
+mode: set
+naviwatcher/internal/config/config.go:58.47,60.16 2 1
+naviwatcher/internal/config/config.go:60.16,62.3 1 1
+naviwatcher/internal/config/config.go:64.2,65.51 2 1
+naviwatcher/internal/config/config.go:65.51,67.3 1 1
+naviwatcher/internal/config/config.go:69.2,71.39 2 1
+naviwatcher/internal/config/config.go:71.39,73.3 1 1
+naviwatcher/internal/config/config.go:75.2,75.18 1 1
+naviwatcher/internal/config/config.go:79.33,80.27 1 1
+naviwatcher/internal/config/config.go:80.27,82.3 1 1
+naviwatcher/internal/config/config.go:83.2,83.26 1 1
+naviwatcher/internal/config/config.go:83.26,85.3 1 1
+naviwatcher/internal/config/config.go:86.2,86.37 1 1
+naviwatcher/internal/config/config.go:86.37,88.3 1 1
+naviwatcher/internal/config/config.go:92.34,93.29 1 1
+naviwatcher/internal/config/config.go:93.29,95.3 1 1
+naviwatcher/internal/config/config.go:96.2,96.30 1 1
+naviwatcher/internal/config/config.go:96.30,98.3 1 1
+naviwatcher/internal/config/config.go:99.2,99.34 1 1
+naviwatcher/internal/config/config.go:99.34,101.3 1 1
+naviwatcher/internal/config/config.go:102.2,102.52 1 1
+naviwatcher/internal/config/config.go:102.52,104.3 1 1
+naviwatcher/internal/config/config.go:105.2,105.74 1 1
+naviwatcher/internal/config/config.go:105.74,107.3 1 1
+naviwatcher/internal/config/config.go:108.2,108.37 1 1
+naviwatcher/internal/config/config.go:108.37,110.3 1 1
+naviwatcher/internal/config/config.go:111.2,111.12 1 1
+naviwatcher/cmd/naviwatcher/main.go:17.13,24.16 5 0
+naviwatcher/cmd/naviwatcher/main.go:24.16,26.3 1 0
+naviwatcher/cmd/naviwatcher/main.go:28.2,36.12 6 0
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+naviwatcher/cmd/naviwatcher/main.go:42.2,42.38 1 0
+naviwatcher/cmd/naviwatcher/main.go:42.38,44.3 1 0
+naviwatcher/cmd/naviwatcher/main.go:46.2,46.37 1 0
+naviwatcher/cmd/naviwatcher/main.go:49.57,57.2 3 1
+naviwatcher/internal/database/artist_settings.go:9.68,15.16 3 1
+naviwatcher/internal/database/artist_settings.go:15.16,17.3 1 1
+naviwatcher/internal/database/artist_settings.go:18.2,18.16 1 1
+naviwatcher/internal/database/artist_settings.go:22.65,27.16 2 1
+naviwatcher/internal/database/artist_settings.go:27.16,29.3 1 0
+naviwatcher/internal/database/artist_settings.go:30.2,30.12 1 1
+naviwatcher/internal/database/artist_settings.go:34.61,38.16 2 1
+naviwatcher/internal/database/artist_settings.go:38.16,40.3 1 0
+naviwatcher/internal/database/artist_settings.go:41.2,44.18 3 1
+naviwatcher/internal/database/artist_settings.go:44.18,46.106 2 1
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+naviwatcher/internal/database/artist_settings.go:49.3,49.31 1 1
+naviwatcher/internal/database/artist_settings.go:51.2,51.35 1 1
+naviwatcher/internal/database/artist_settings.go:51.35,53.3 1 0
+naviwatcher/internal/database/artist_settings.go:54.2,54.21 1 1
+naviwatcher/internal/database/artist_settings.go:59.84,70.32 4 1
+naviwatcher/internal/database/artist_settings.go:70.32,71.20 1 1
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+naviwatcher/internal/database/artist_settings.go:74.3,74.22 1 1
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+naviwatcher/internal/database/artist_settings.go:77.3,78.27 2 1
+naviwatcher/internal/database/artist_settings.go:81.2,81.20 1 1
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+naviwatcher/internal/database/artist_settings.go:96.2,96.23 1 1
+naviwatcher/internal/database/artist_settings.go:96.23,98.3 1 1
+naviwatcher/internal/database/artist_settings.go:100.2,100.12 1 1
+naviwatcher/internal/database/database.go:17.38,19.16 2 1
+naviwatcher/internal/database/database.go:19.16,21.3 1 0
+naviwatcher/internal/database/database.go:24.2,24.64 1 1
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+naviwatcher/internal/database/database.go:49.31,55.19 1 1
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+naviwatcher/internal/database/database.go:126.55,129.2 2 1
+naviwatcher/internal/database/external_releases.go:9.72,15.16 3 1
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+naviwatcher/internal/database/external_releases.go:55.2,55.21 1 1
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+naviwatcher/internal/database/external_releases.go:66.2,69.18 3 1
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+naviwatcher/internal/database/external_releases.go:96.23,98.3 1 1
+naviwatcher/internal/database/external_releases.go:100.2,100.12 1 1
+naviwatcher/internal/database/notifications.go:8.54,13.16 2 1
+naviwatcher/internal/database/notifications.go:13.16,15.3 1 0
+naviwatcher/internal/database/notifications.go:16.2,16.12 1 1
+naviwatcher/internal/database/notifications.go:20.60,25.16 3 1
+naviwatcher/internal/database/notifications.go:25.16,27.3 1 0
+naviwatcher/internal/database/notifications.go:28.2,28.23 1 1
+naviwatcher/internal/database/notifications.go:32.63,39.16 2 1
+naviwatcher/internal/database/notifications.go:39.16,41.3 1 0
+naviwatcher/internal/database/notifications.go:42.2,45.18 3 1
+naviwatcher/internal/database/notifications.go:45.18,47.106 2 1
+naviwatcher/internal/database/notifications.go:47.106,49.4 1 0
+naviwatcher/internal/database/notifications.go:50.3,50.31 1 1
+naviwatcher/internal/database/notifications.go:52.2,52.35 1 1
+naviwatcher/internal/database/notifications.go:52.35,54.3 1 0
+naviwatcher/internal/database/notifications.go:55.2,55.21 1 1
+naviwatcher/internal/database/notifications.go:60.65,65.16 3 1
+naviwatcher/internal/database/notifications.go:65.16,67.3 1 1
+naviwatcher/internal/database/notifications.go:68.2,68.20 1 1

internal/config/config_test.go

@@ -30,7 +30,7 @@ musicbrainz:
 telegram:
   enabled: true
   token: "abc123"
-  chat: "chat456"
+  chat_id: "chat456"
   cron_schedule: "0 10 * * *"
 
 scanner:
@@ -59,6 +59,9 @@ scanner:
 	if cfg.Navidrome.URL != "http://navidrome:4533" {
 		t.Errorf("expected navidrome url http://navidrome:4533, got %s", cfg.Navidrome.URL)
 	}
+	if cfg.Telegram.ChatID != "chat456" {
+		t.Errorf("expected telegram chat_id chat456, got %s", cfg.Telegram.ChatID)
+	}
 	if cfg.Navidrome.User != "service" {
 		t.Errorf("expected navidrome user service, got %s", cfg.Navidrome.User)
 	}
@@ -137,7 +140,6 @@ func TestLoadConfig_InvalidPort(t *testing.T) {
 		name string
 		port int
 	}{
-		{"port zero with explicit 0 and no default override", 0},
 		{"port too high", 70000},
 		{"port negative", -1},
 	}
@@ -147,32 +149,12 @@ func TestLoadConfig_InvalidPort(t *testing.T) {
 			dir := t.TempDir()
 			path := filepath.Join(dir, "config.yaml")
 
-			yaml := `
+			yaml := buildConfigWithPort(tt.port)
-navidrome:
-  url: "http://localhost:4533"
-  user: "u"
-  password: "p"
-
-musicbrainz:
-  user_agent: "NaviWatcher/1.0 ( test@example.com )"
-
-server:
-  port: ` + string(rune('0'+tt.port%10)) + `
-`
-			// Use Sprintf for proper port formatting
-			yaml = buildConfigWithPort(path, tt.port)
 			if err := os.WriteFile(path, []byte(yaml), 0644); err != nil {
 				t.Fatalf("failed to write config: %v", err)
 			}
 
 			_, err := LoadConfig(path)
-			if tt.port == 0 {
-				// port 0 gets defaulted to 8080, which is valid
-				if err != nil {
-					t.Fatalf("port 0 should get default, got error: %v", err)
-				}
-				return
-			}
 			if err == nil {
 				t.Fatalf("expected error for port %d, got nil", tt.port)
 			}
@@ -180,7 +162,7 @@ server:
 	}
 }
 
-func buildConfigWithPort(path string, port int) string {
+func buildConfigWithPort(port int) string {
 	return "navidrome:\n  url: \"http://localhost:4533\"\n  user: \"u\"\n  password: \"p\"\n\nmusicbrainz:\n  user_agent: \"NaviWatcher/1.0 ( test@example.com )\"\n\nserver:\n  port: " + fmt.Sprintf("%d", port) + "\n"
 }
 
@@ -349,7 +331,7 @@ func TestValidate_BoundaryPort(t *testing.T) {
 			dir := t.TempDir()
 			path := filepath.Join(dir, "config.yaml")
 
-			yaml := buildConfigWithPort(path, tt.port)
+			yaml := buildConfigWithPort(tt.port)
 			if err := os.WriteFile(path, []byte(yaml), 0644); err != nil {
 				t.Fatalf("failed to write config: %v", err)
 			}

internal/database/database.go

@@ -26,6 +26,18 @@ func New(dbPath string) (*DB, error) {
 		return nil, fmt.Errorf("set WAL mode: %w", err)
 	}
 
+	// Enable foreign key enforcement.
+	if _, err := conn.Exec("PRAGMA foreign_keys=ON"); err != nil {
+		conn.Close()
+		return nil, fmt.Errorf("enable foreign keys: %w", err)
+	}
+
+	// Set busy timeout to handle concurrent write contention.
+	if _, err := conn.Exec("PRAGMA busy_timeout=5000"); err != nil {
+		conn.Close()
+		return nil, fmt.Errorf("set busy timeout: %w", err)
+	}
+
 	db := &DB{conn: conn}
 	if err := db.migrate(); err != nil {
 		conn.Close()
@@ -74,7 +86,7 @@ func (db *DB) migrate() error {
 			name: "002_create_external_releases",
 			sql: `CREATE TABLE IF NOT EXISTS external_releases (
 				rgid TEXT PRIMARY KEY,
-				artist_id TEXT NOT NULL,
+				artist_id TEXT NOT NULL REFERENCES artist_settings(id),
 				title TEXT NOT NULL,
 				type TEXT,
 				release_date TEXT,
@@ -84,9 +96,8 @@ func (db *DB) migrate() error {
 		{
 			name: "003_create_notifications_sent",
 			sql: `CREATE TABLE IF NOT EXISTS notifications_sent (
-				rgid TEXT NOT NULL,
+				rgid TEXT PRIMARY KEY REFERENCES external_releases(rgid),
-				sent_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+				sent_at DATETIME DEFAULT CURRENT_TIMESTAMP
-				PRIMARY KEY (rgid, sent_at)
 			);`,
 		},
 	}

internal/database/database_test.go

@@ -119,6 +119,11 @@ func TestExternalReleasesSchema(t *testing.T) {
 	}
 	defer db.Close()
 
+	// Insert parent artist first (FK requirement).
+	_, err = db.Conn().Exec("INSERT INTO artist_settings (id, name) VALUES (?, ?)", "artist-1", "Test Artist")
+	if err != nil {
+		t.Fatalf("insert artist: %v", err)
+	}
 	_, err = db.Conn().Exec(
 		"INSERT INTO external_releases (rgid, artist_id, title, type, release_date, is_ignored) VALUES (?, ?, ?, ?, ?, ?)",
 		"rgid-1", "artist-1", "Test Album", "album", "2024-01-01", false,
@@ -150,6 +155,15 @@ func TestNotificationsSentSchema(t *testing.T) {
 	}
 	defer db.Close()
 
+	// Insert parent artist and release first (FK requirements).
+	_, err = db.Conn().Exec("INSERT INTO artist_settings (id, name) VALUES (?, ?)", "artist-1", "Test Artist")
+	if err != nil {
+		t.Fatalf("insert artist: %v", err)
+	}
+	_, err = db.Conn().Exec("INSERT INTO external_releases (rgid, artist_id, title) VALUES (?, ?, ?)", "rgid-1", "artist-1", "Test Album")
+	if err != nil {
+		t.Fatalf("insert release: %v", err)
+	}
 	_, err = db.Conn().Exec(
 		"INSERT INTO notifications_sent (rgid) VALUES (?)",
 		"rgid-1",
@@ -192,6 +206,6 @@ func TestMigrationTracking(t *testing.T) {
 
 	// We have 3 recorded migrations: artist_settings, external_releases, notifications_sent.
 	if count != 3 {
-		t.Errorf("expected 4 applied migrations, got %d", count)
+		t.Errorf("expected 3 applied migrations, got %d", count)
 	}
 }

internal/database/external_releases_test.go

@@ -5,6 +5,15 @@ import (
 	"testing"
 )
 
+// insertTestArtist inserts a minimal artist_settings row for use in tests that need FK satisfaction.
+func insertTestArtist(db *DB, id string) error {
+	_, err := db.Conn().Exec(
+		"INSERT OR IGNORE INTO artist_settings (id, name) VALUES (?, ?)",
+		id, "Test Artist "+id,
+	)
+	return err
+}
+
 // TestGetExternalRelease_Found verifies retrieving an existing release.
 func TestGetExternalRelease_Found(t *testing.T) {
 	db, err := New(":memory:")
@@ -13,7 +22,9 @@ func TestGetExternalRelease_Found(t *testing.T) {
 	}
 	defer db.Close()
 
-	// Insert a row directly.
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist: %v", err)
+	}
 	_, err = db.Conn().Exec(
 		"INSERT INTO external_releases (rgid, artist_id, title, type, release_date, is_ignored) VALUES (?, ?, ?, ?, ?, ?)",
 		"rgid-1", "artist-1", "Test Album", "album", "2024-01-01", false,
@@ -78,6 +89,9 @@ func TestSaveExternalRelease_Insert(t *testing.T) {
 		IsIgnored:   false,
 	}
 
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist: %v", err)
+	}
 	if err := SaveExternalRelease(db, r); err != nil {
 		t.Fatalf("SaveExternalRelease() error: %v", err)
 	}
@@ -102,6 +116,10 @@ func TestSaveExternalRelease_Update(t *testing.T) {
 	}
 	defer db.Close()
 
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist: %v", err)
+	}
+
 	// Insert initial row.
 	r1 := &ExternalRelease{
 		RGID:        "rgid-1",
@@ -177,6 +195,12 @@ func TestGetExternalReleasesByArtist_Populated(t *testing.T) {
 		{RGID: "rg3", ArtistID: "artist-b", Title: "Album B1", Type: "single", ReleaseDate: "2024-03-01"},
 	}
 
+	if err := insertTestArtist(db, "artist-a"); err != nil {
+		t.Fatalf("insertTestArtist(artist-a): %v", err)
+	}
+	if err := insertTestArtist(db, "artist-b"); err != nil {
+		t.Fatalf("insertTestArtist(artist-b): %v", err)
+	}
 	for _, r := range releases {
 		if err := SaveExternalRelease(db, &r); err != nil {
 			t.Fatalf("SaveExternalRelease(%s) error: %v", r.RGID, err)
@@ -243,6 +267,12 @@ func TestGetIgnoredReleases_Populated(t *testing.T) {
 		{RGID: "rg3", ArtistID: "a2", Title: "Another Ignored", IsIgnored: true},
 	}
 
+	if err := insertTestArtist(db, "a1"); err != nil {
+		t.Fatalf("insertTestArtist(a1): %v", err)
+	}
+	if err := insertTestArtist(db, "a2"); err != nil {
+		t.Fatalf("insertTestArtist(a2): %v", err)
+	}
 	for _, r := range releases {
 		if err := SaveExternalRelease(db, &r); err != nil {
 			t.Fatalf("SaveExternalRelease(%s) error: %v", r.RGID, err)
@@ -279,6 +309,9 @@ func TestSetReleaseIgnored_SetTrue(t *testing.T) {
 		Title:     "Test Album",
 		IsIgnored: false,
 	}
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist: %v", err)
+	}
 	if err := SaveExternalRelease(db, r); err != nil {
 		t.Fatalf("SaveExternalRelease() error: %v", err)
 	}
@@ -310,6 +343,9 @@ func TestSetReleaseIgnored_SetFalse(t *testing.T) {
 		Title:     "Test Album",
 		IsIgnored: true,
 	}
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist: %v", err)
+	}
 	if err := SaveExternalRelease(db, r); err != nil {
 		t.Fatalf("SaveExternalRelease() error: %v", err)
 	}

internal/database/notifications.go

@@ -7,7 +7,7 @@ import (
 // MarkNotificationSent records that a notification has been sent for the given RGID.
 func MarkNotificationSent(db *DB, rgid string) error {
 	_, err := db.Conn().Exec(
-		"INSERT OR IGNORE INTO notifications_sent (rgid) VALUES (?)",
+		"INSERT OR REPLACE INTO notifications_sent (rgid) VALUES (?)",
 		rgid,
 	)
 	if err != nil {
@@ -60,7 +60,7 @@ func GetUnnotifiedReleases(db *DB) ([]ExternalRelease, error) {
 func GetNotificationSentAt(db *DB, rgid string) (string, error) {
 	var sentAt string
 	err := db.Conn().QueryRow(
-		"SELECT sent_at FROM notifications_sent WHERE rgid = ?", rgid,
+		"SELECT sent_at FROM notifications_sent WHERE rgid = ? ORDER BY sent_at DESC LIMIT 1", rgid,
 	).Scan(&sentAt)
 	if err != nil {
 		return "", err

internal/database/notifications_test.go

@@ -5,6 +5,15 @@ import (
 	"testing"
 )
 
+// insertTestRelease inserts a minimal external_releases row for use in tests that need FK satisfaction.
+func insertTestRelease(db *DB, rgid, artistID string) error {
+	_, err := db.Conn().Exec(
+		"INSERT OR IGNORE INTO external_releases (rgid, artist_id, title) VALUES (?, ?, ?)",
+		rgid, artistID, "Test Release "+rgid,
+	)
+	return err
+}
+
 // TestMarkNotificationSent_New verifies inserting a new notification record.
 func TestMarkNotificationSent_New(t *testing.T) {
 	db, err := New(":memory:")
@@ -13,6 +22,12 @@ func TestMarkNotificationSent_New(t *testing.T) {
 	}
 	defer db.Close()
 
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist: %v", err)
+	}
+	if err := insertTestRelease(db, "rgid-1", "artist-1"); err != nil {
+		t.Fatalf("insertTestRelease: %v", err)
+	}
 	if err := MarkNotificationSent(db, "rgid-1"); err != nil {
 		t.Fatalf("MarkNotificationSent() error: %v", err)
 	}
@@ -34,6 +49,12 @@ func TestMarkNotificationSent_Idempotent(t *testing.T) {
 	}
 	defer db.Close()
 
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist: %v", err)
+	}
+	if err := insertTestRelease(db, "rgid-1", "artist-1"); err != nil {
+		t.Fatalf("insertTestRelease: %v", err)
+	}
 	if err := MarkNotificationSent(db, "rgid-1"); err != nil {
 		t.Fatalf("first MarkNotificationSent() error: %v", err)
 	}
@@ -60,6 +81,12 @@ func TestIsNotificationSent_True(t *testing.T) {
 	}
 	defer db.Close()
 
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist: %v", err)
+	}
+	if err := insertTestRelease(db, "rgid-1", "artist-1"); err != nil {
+		t.Fatalf("insertTestRelease: %v", err)
+	}
 	if err := MarkNotificationSent(db, "rgid-1"); err != nil {
 		t.Fatalf("MarkNotificationSent() error: %v", err)
 	}
@@ -118,6 +145,12 @@ func TestGetUnnotifiedReleases_AllUnnotified(t *testing.T) {
 		{RGID: "rg3", ArtistID: "artist-2", Title: "Single 1", Type: "single", ReleaseDate: "2024-03-01"},
 	}
 
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist(artist-1): %v", err)
+	}
+	if err := insertTestArtist(db, "artist-2"); err != nil {
+		t.Fatalf("insertTestArtist(artist-2): %v", err)
+	}
 	for _, r := range releases {
 		if err := SaveExternalRelease(db, &r); err != nil {
 			t.Fatalf("SaveExternalRelease(%s) error: %v", r.RGID, err)
@@ -147,6 +180,12 @@ func TestGetUnnotifiedReleases_SomeNotified(t *testing.T) {
 		{RGID: "rg3", ArtistID: "artist-2", Title: "Single 1", Type: "single", ReleaseDate: "2024-03-01"},
 	}
 
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist(artist-1): %v", err)
+	}
+	if err := insertTestArtist(db, "artist-2"); err != nil {
+		t.Fatalf("insertTestArtist(artist-2): %v", err)
+	}
 	for _, r := range releases {
 		if err := SaveExternalRelease(db, &r); err != nil {
 			t.Fatalf("SaveExternalRelease(%s) error: %v", r.RGID, err)
@@ -189,6 +228,9 @@ func TestGetUnnotifiedReleases_AllNotified(t *testing.T) {
 		{RGID: "rg2", ArtistID: "artist-1", Title: "Album 2"},
 	}
 
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist(artist-1): %v", err)
+	}
 	for _, r := range releases {
 		if err := SaveExternalRelease(db, &r); err != nil {
 			t.Fatalf("SaveExternalRelease(%s) error: %v", r.RGID, err)
@@ -236,6 +278,15 @@ func TestMarkNotificationSent_MultipleReleases(t *testing.T) {
 	}
 	defer db.Close()
 
+	if err := insertTestArtist(db, "artist-1"); err != nil {
+		t.Fatalf("insertTestArtist: %v", err)
+	}
+	for _, rgid := range []string{"rg1", "rg2", "rg3"} {
+		if err := insertTestRelease(db, rgid, "artist-1"); err != nil {
+			t.Fatalf("insertTestRelease(%s): %v", rgid, err)
+		}
+	}
+
 	rgids := []string{"rg1", "rg2", "rg3"}
 	for _, rgid := range rgids {
 		if err := MarkNotificationSent(db, rgid); err != nil {