refactor: define CatalogDB and CatalogTx interfaces with SQLite implementation

Author: retran

mdl/catalog/catalogdb.go

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: Apache-2.0
+
+package catalog
+
+import "database/sql"
+
+// CatalogDB abstracts the database layer used by Catalog and LintContext.
+// The primary implementation wraps modernc.org/sqlite for native builds;
+// a js/wasm build will supply a host-backed implementation.
+type CatalogDB interface {
+	Query(query string, args ...any) (*sql.Rows, error)
+	QueryRow(query string, args ...any) *sql.Row
+	Exec(query string, args ...any) (sql.Result, error)
+	Begin() (CatalogTx, error)
+	Close() error
+}
+
+// CatalogTx abstracts a database transaction. Builder uses this for bulk
+// inserts with prepared statements.
+type CatalogTx interface {
+	Prepare(query string) (*sql.Stmt, error)
+	Exec(query string, args ...any) (sql.Result, error)
+	QueryRow(query string, args ...any) *sql.Row
+	Commit() error
+	Rollback() error
+}

mdl/catalog/catalogdb_sqlite.go

@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: Apache-2.0
+
+//go:build !js
+
+package catalog
+
+import (
+	"database/sql"
+
+	_ "modernc.org/sqlite"
+)
+
+// SqliteCatalogDB wraps *sql.DB from modernc.org/sqlite.
+type SqliteCatalogDB struct {
+	db *sql.DB
+}
+
+// NewSqliteCatalogDB opens an in-memory SQLite database.
+func NewSqliteCatalogDB() (*SqliteCatalogDB, error) {
+	db, err := sql.Open("sqlite", ":memory:")
+	if err != nil {
+		return nil, err
+	}
+	if _, err := db.Exec("PRAGMA foreign_keys = ON"); err != nil {
+		db.Close()
+		return nil, err
+	}
+	return &SqliteCatalogDB{db: db}, nil
+}
+
+// NewSqliteCatalogDBFromFile opens a file-based SQLite database.
+func NewSqliteCatalogDBFromFile(path string) (*SqliteCatalogDB, error) {
+	db, err := sql.Open("sqlite", path)
+	if err != nil {
+		return nil, err
+	}
+	if _, err := db.Exec("PRAGMA foreign_keys = ON"); err != nil {
+		db.Close()
+		return nil, err
+	}
+	return &SqliteCatalogDB{db: db}, nil
+}
+
+func (s *SqliteCatalogDB) Query(query string, args ...any) (*sql.Rows, error) {
+	return s.db.Query(query, args...)
+}
+
+func (s *SqliteCatalogDB) QueryRow(query string, args ...any) *sql.Row {
+	return s.db.QueryRow(query, args...)
+}
+
+func (s *SqliteCatalogDB) Exec(query string, args ...any) (sql.Result, error) {
+	return s.db.Exec(query, args...)
+}
+
+func (s *SqliteCatalogDB) Begin() (CatalogTx, error) {
+	return s.db.Begin()
+}
+
+func (s *SqliteCatalogDB) Close() error {
+	return s.db.Close()
+}
+
+// RawDB returns the underlying *sql.DB. Used only for SQLite-specific
+// operations like VACUUM INTO in SaveToFile.
+func (s *SqliteCatalogDB) RawDB() *sql.DB {
+	return s.db
+}