chore: import upstream snapshot with attribution

internal/sources/sqlite/sqlite.go

@@ -0,0 +1,175 @@
+// Copyright 2025 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package sqlite
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"fmt"
+
+	"github.com/goccy/go-yaml"
+	"github.com/googleapis/mcp-toolbox/internal/sources"
+	"github.com/googleapis/mcp-toolbox/internal/sources/sqlcommenter"
+	"github.com/googleapis/mcp-toolbox/internal/util/orderedmap"
+	"go.opentelemetry.io/otel/trace"
+	_ "modernc.org/sqlite" // Pure Go SQLite driver
+)
+
+const SourceType string = "sqlite"
+
+// validate interface
+var _ sources.SourceConfig = Config{}
+
+func init() {
+	if !sources.Register(SourceType, newConfig) {
+		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	}
+}
+
+func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources.SourceConfig, error) {
+	actual := Config{Name: name}
+	if err := decoder.DecodeContext(ctx, &actual); err != nil {
+		return nil, err
+	}
+	return actual, nil
+}
+
+type Config struct {
+	Name         string `yaml:"name" validate:"required"`
+	Type         string `yaml:"type" validate:"required"`
+	Database     string `yaml:"database" validate:"required"` // Path to SQLite database file
+	SQLCommenter *bool  `yaml:"sqlCommenter"`
+}
+
+func (r Config) SourceConfigType() string {
+	return SourceType
+}
+
+func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
+	db, err := initSQLiteConnection(ctx, tracer, r.Name, r.Database)
+	if err != nil {
+		return nil, fmt.Errorf("unable to create db connection: %w", err)
+	}
+
+	err = db.PingContext(context.Background())
+	if err != nil {
+		return nil, fmt.Errorf("unable to connect successfully: %w", err)
+	}
+
+	s := &Source{
+		Config: r,
+		Db:     db,
+	}
+	return s, nil
+}
+
+var _ sources.Source = &Source{}
+
+type Source struct {
+	Config
+	Db *sql.DB
+}
+
+func (s *Source) SourceType() string {
+	return SourceType
+}
+
+func (s *Source) ToConfig() sources.SourceConfig {
+	return s.Config
+}
+
+func (s *Source) SQLiteDB() *sql.DB {
+	return s.Db
+}
+
+func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (any, error) {
+	// Execute the SQL query with parameters
+	statement = sqlcommenter.PrependComment(ctx, statement, SourceType, s.SQLCommenter)
+	rows, err := s.SQLiteDB().QueryContext(ctx, statement, params...)
+	if err != nil {
+		return nil, fmt.Errorf("unable to execute query: %w", err)
+	}
+	defer rows.Close()
+
+	// Get column names
+	cols, err := rows.Columns()
+	if err != nil {
+		return nil, fmt.Errorf("unable to get column names: %w", err)
+	}
+
+	// The sqlite driver does not support ColumnTypes, so we can't get the
+	// underlying database type of the columns. We'll have to rely on the
+	// generic `any` type and then handle the JSON data separately.
+	rawValues := make([]any, len(cols))
+	values := make([]any, len(cols))
+	for i := range rawValues {
+		values[i] = &rawValues[i]
+	}
+
+	// Prepare the result slice
+	out := []any{}
+	for rows.Next() {
+		if err := rows.Scan(values...); err != nil {
+			return nil, fmt.Errorf("unable to scan row: %w", err)
+		}
+
+		// Create a map for this row
+		row := orderedmap.Row{}
+		for i, name := range cols {
+			val := rawValues[i]
+			// Handle nil values
+			if val == nil {
+				row.Add(name, nil)
+				continue
+			}
+			// Handle JSON data
+			if jsonString, ok := val.(string); ok {
+				var unmarshaledData any
+				if json.Unmarshal([]byte(jsonString), &unmarshaledData) == nil {
+					row.Add(name, unmarshaledData)
+					continue
+				}
+			}
+			// Store the value in the map
+			row.Add(name, val)
+		}
+		out = append(out, row)
+	}
+
+	if err = rows.Err(); err != nil {
+		return nil, fmt.Errorf("error iterating rows: %w", err)
+	}
+
+	return out, nil
+}
+
+func initSQLiteConnection(ctx context.Context, tracer trace.Tracer, name, dbPath string) (*sql.DB, error) {
+	//nolint:all // Reassigned ctx
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	defer span.End()
+
+	// Open database connection
+	db, err := sql.Open("sqlite", dbPath)
+	if err != nil {
+		return nil, fmt.Errorf("sql.Open: %w", err)
+	}
+
+	// Set some reasonable defaults for SQLite
+	db.SetMaxOpenConns(1) // SQLite only supports one writer at a time
+	db.SetMaxIdleConns(1)
+
+	return db, nil
+}