fix(db): improve database connection handling and reconnection logic

* Added a database factory function to allow reconnection when the database is closed.
* Implemented mutex locks for safe concurrent access to the database connection.
* Updated all database query methods to handle reconnection attempts on closed connections.
* Enhanced error handling for database operations across multiple providers.

pkg/common/adapters/database/pgsql.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"reflect"
 	"strings"
+	"sync"
 
 	"github.com/bitechdev/ResolveSpec/pkg/common"
 	"github.com/bitechdev/ResolveSpec/pkg/logger"
@@ -17,6 +18,8 @@ import (
 // This provides a lightweight PostgreSQL adapter without ORM overhead
 type PgSQLAdapter struct {
 	db         *sql.DB
+	dbMu       sync.RWMutex
+	dbFactory  func() (*sql.DB, error)
 	driverName string
 }
 
@@ -31,6 +34,36 @@ func NewPgSQLAdapter(db *sql.DB, driverName ...string) *PgSQLAdapter {
 	return &PgSQLAdapter{db: db, driverName: name}
 }
 
+// WithDBFactory configures a factory used to reopen the database connection if it is closed.
+func (p *PgSQLAdapter) WithDBFactory(factory func() (*sql.DB, error)) *PgSQLAdapter {
+	p.dbFactory = factory
+	return p
+}
+
+func (p *PgSQLAdapter) getDB() *sql.DB {
+	p.dbMu.RLock()
+	defer p.dbMu.RUnlock()
+	return p.db
+}
+
+func (p *PgSQLAdapter) reconnectDB() error {
+	if p.dbFactory == nil {
+		return fmt.Errorf("no db factory configured for reconnect")
+	}
+	newDB, err := p.dbFactory()
+	if err != nil {
+		return err
+	}
+	p.dbMu.Lock()
+	p.db = newDB
+	p.dbMu.Unlock()
+	return nil
+}
+
+func isDBClosed(err error) bool {
+	return err != nil && strings.Contains(err.Error(), "sql: database is closed")
+}
+
 // EnableQueryDebug enables query debugging for development
 func (p *PgSQLAdapter) EnableQueryDebug() {
 	logger.Info("PgSQL query debug mode - logging enabled via logger")
@@ -38,7 +71,7 @@ func (p *PgSQLAdapter) EnableQueryDebug() {
 
 func (p *PgSQLAdapter) NewSelect() common.SelectQuery {
 	return &PgSQLSelectQuery{
-		db:         p.db,
+		db:         p.getDB(),
 		driverName: p.driverName,
 		columns:    []string{"*"},
 		args:       make([]interface{}, 0),
@@ -47,7 +80,7 @@ func (p *PgSQLAdapter) NewSelect() common.SelectQuery {
 
 func (p *PgSQLAdapter) NewInsert() common.InsertQuery {
 	return &PgSQLInsertQuery{
-		db:         p.db,
+		db:         p.getDB(),
 		driverName: p.driverName,
 		values:     make(map[string]interface{}),
 	}
@@ -55,7 +88,7 @@ func (p *PgSQLAdapter) NewInsert() common.InsertQuery {
 
 func (p *PgSQLAdapter) NewUpdate() common.UpdateQuery {
 	return &PgSQLUpdateQuery{
-		db:           p.db,
+		db:           p.getDB(),
 		driverName:   p.driverName,
 		sets:         make(map[string]interface{}),
 		args:         make([]interface{}, 0),
@@ -65,7 +98,7 @@ func (p *PgSQLAdapter) NewUpdate() common.UpdateQuery {
 
 func (p *PgSQLAdapter) NewDelete() common.DeleteQuery {
 	return &PgSQLDeleteQuery{
-		db:           p.db,
+		db:           p.getDB(),
 		driverName:   p.driverName,
 		args:         make([]interface{}, 0),
 		whereClauses: make([]string, 0),
@@ -79,7 +112,14 @@ func (p *PgSQLAdapter) Exec(ctx context.Context, query string, args ...interface
 		}
 	}()
 	logger.Debug("PgSQL Exec: %s [args: %v]", query, args)
-	result, err := p.db.ExecContext(ctx, query, args...)
+	var result sql.Result
+	run := func() error { var e error; result, e = p.getDB().ExecContext(ctx, query, args...); return e }
+	err = run()
+	if isDBClosed(err) {
+		if reconnErr := p.reconnectDB(); reconnErr == nil {
+			err = run()
+		}
+	}
 	if err != nil {
 		logger.Error("PgSQL Exec failed: %v", err)
 		return nil, err
@@ -94,7 +134,14 @@ func (p *PgSQLAdapter) Query(ctx context.Context, dest interface{}, query string
 		}
 	}()
 	logger.Debug("PgSQL Query: %s [args: %v]", query, args)
-	rows, err := p.db.QueryContext(ctx, query, args...)
+	var rows *sql.Rows
+	run := func() error { var e error; rows, e = p.getDB().QueryContext(ctx, query, args...); return e }
+	err = run()
+	if isDBClosed(err) {
+		if reconnErr := p.reconnectDB(); reconnErr == nil {
+			err = run()
+		}
+	}
 	if err != nil {
 		logger.Error("PgSQL Query failed: %v", err)
 		return err
@@ -105,7 +152,7 @@ func (p *PgSQLAdapter) Query(ctx context.Context, dest interface{}, query string
 }
 
 func (p *PgSQLAdapter) BeginTx(ctx context.Context) (common.Database, error) {
-	tx, err := p.db.BeginTx(ctx, nil)
+	tx, err := p.getDB().BeginTx(ctx, nil)
 	if err != nil {
 		return nil, err
 	}
@@ -127,7 +174,7 @@ func (p *PgSQLAdapter) RunInTransaction(ctx context.Context, fn func(common.Data
 		}
 	}()
 
-	tx, err := p.db.BeginTx(ctx, nil)
+	tx, err := p.getDB().BeginTx(ctx, nil)
 	if err != nil {
 		return err
 	}