Ensure db directory exists (#254)

* Ensure db directory exists.

* Add tests.

Author: cmrigney

pkg/db/db.go

@@ -5,6 +5,7 @@ import (
 	"embed"
 	"errors"
 	"fmt"
+	"os"
 	"path/filepath"
 
 	"github.com/golang-migrate/migrate/v4"
@@ -60,6 +61,8 @@ func New(opts ...Option) (DAO, error) {
 		o.dbFile = dbFile
 	}
 
+	ensureDirectoryExists(o.dbFile)
+
 	db, err := sql.Open("sqlite", "file:"+o.dbFile+"?_pragma=busy_timeout(5000)&_pragma=foreign_keys(ON)")
 	if err != nil {
 		return nil, fmt.Errorf("failed to open database: %w", err)
@@ -102,6 +105,13 @@ func DefaultDatabaseFilename() (string, error) {
 	return filepath.Join(homeDir, ".docker", "mcp", "mcp-toolkit.db"), nil
 }
 
+func ensureDirectoryExists(path string) {
+	dir := filepath.Dir(path)
+	if _, err := os.Stat(dir); os.IsNotExist(err) {
+		_ = os.MkdirAll(dir, 0o755)
+	}
+}
+
 func txClose(tx *sqlx.Tx, err *error) {
 	if err == nil || *err == nil {
 		return

pkg/db/db_test.go

@@ -0,0 +1,33 @@
+package db
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestNewCreatesDirectoryWhenNotExists(t *testing.T) {
+	// Create a temporary directory for testing
+	tempDir := t.TempDir()
+
+	// Create a nested path that doesn't exist yet
+	nonExistentDir := filepath.Join(tempDir, "nested", "directories", "that", "dont", "exist")
+	dbFile := filepath.Join(nonExistentDir, "test.db")
+
+	// Verify the directory doesn't exist before creating the database
+	_, err := os.Stat(nonExistentDir)
+	assert.True(t, os.IsNotExist(err), "Directory should not exist before database creation")
+
+	// Create the database - this should create the directory
+	dao, err := New(WithDatabaseFile(dbFile))
+	require.NoError(t, err)
+	require.NotNil(t, dao)
+
+	// Verify the directory was created
+	stat, err := os.Stat(nonExistentDir)
+	require.NoError(t, err, "Directory should exist after database creation")
+	assert.True(t, stat.IsDir(), "Created path should be a directory")
+}