Fixed computed columns

.gitignore

@@ -23,4 +23,5 @@ go.work.sum
 
 # env file
 .env
-bin/
+bin/
+test.db

pkg/common/adapters/database/bun.go

@@ -119,6 +119,12 @@ func (b *BunSelectQuery) Column(columns ...string) common.SelectQuery {
 	return b
 }
 
+func (b *BunSelectQuery) ColumnExpr(query string, args ...interface{}) common.SelectQuery {
+	b.query = b.query.ColumnExpr(query, args)
+
+	return b
+}
+
 func (b *BunSelectQuery) Where(query string, args ...interface{}) common.SelectQuery {
 	b.query = b.query.Where(query, args...)
 	return b
@@ -238,6 +244,10 @@ func (b *BunSelectQuery) Scan(ctx context.Context, dest interface{}) error {
 	return b.query.Scan(ctx, dest)
 }
 
+func (b *BunSelectQuery) ScanModel(ctx context.Context) error {
+	return b.query.Scan(ctx)
+}
+
 func (b *BunSelectQuery) Count(ctx context.Context) (int, error) {
 	// If Model() was set, use bun's native Count() which works properly
 	if b.hasModel {

pkg/common/adapters/database/gorm.go

@@ -105,6 +105,11 @@ func (g *GormSelectQuery) Column(columns ...string) common.SelectQuery {
 	return g
 }
 
+func (g *GormSelectQuery) ColumnExpr(query string, args ...interface{}) common.SelectQuery {
+	g.db = g.db.Select(query, args...)
+	return g
+}
+
 func (g *GormSelectQuery) Where(query string, args ...interface{}) common.SelectQuery {
 	g.db = g.db.Where(query, args...)
 	return g
@@ -221,6 +226,13 @@ func (g *GormSelectQuery) Scan(ctx context.Context, dest interface{}) error {
 	return g.db.WithContext(ctx).Find(dest).Error
 }
 
+func (g *GormSelectQuery) ScanModel(ctx context.Context) error {
+	if g.db.Statement.Model == nil {
+		return fmt.Errorf("ScanModel requires Model() to be set before scanning")
+	}
+	return g.db.WithContext(ctx).Find(g.db.Statement.Model).Error
+}
+
 func (g *GormSelectQuery) Count(ctx context.Context) (int, error) {
 	var count int64
 	err := g.db.WithContext(ctx).Count(&count).Error

pkg/common/interfaces.go

@@ -26,6 +26,7 @@ type SelectQuery interface {
 	Model(model interface{}) SelectQuery
 	Table(table string) SelectQuery
 	Column(columns ...string) SelectQuery
+	ColumnExpr(query string, args ...interface{}) SelectQuery
 	Where(query string, args ...interface{}) SelectQuery
 	WhereOr(query string, args ...interface{}) SelectQuery
 	Join(query string, args ...interface{}) SelectQuery
@@ -39,6 +40,7 @@ type SelectQuery interface {
 
 	// Execution methods
 	Scan(ctx context.Context, dest interface{}) error
+	ScanModel(ctx context.Context) error
 	Count(ctx context.Context) (int, error)
 	Exists(ctx context.Context) (bool, error)
 }

pkg/resolvespec/handler.go

@@ -196,6 +196,13 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 		query = query.Column(options.Columns...)
 	}
 
+	if len(options.ComputedColumns) > 0 {
+		for _, cu := range options.ComputedColumns {
+			logger.Debug("Applying computed column: %s", cu.Name)
+			query = query.ColumnExpr("(?) AS "+cu.Name, cu.Expression)
+		}
+	}
+
 	// Apply preloading
 	if len(options.Preload) > 0 {
 		query = h.applyPreloads(model, query, options.Preload)

pkg/restheadspec/handler.go

@@ -253,6 +253,21 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 		query = query.Table(tableName)
 	}
 
+	// Apply ComputedQL fields if any
+	if len(options.ComputedQL) > 0 {
+		for colName, colExpr := range options.ComputedQL {
+			logger.Debug("Applying computed column: %s", colName)
+			query = query.ColumnExpr("(?) AS "+colName, colExpr)
+		}
+	}
+
+	if len(options.ComputedColumns) > 0 {
+		for _, cu := range options.ComputedColumns {
+			logger.Debug("Applying computed column: %s", cu.Name)
+			query = query.ColumnExpr("(?) AS "+cu.Name, cu.Expression)
+		}
+	}
+
 	// Apply column selection
 	if len(options.Columns) > 0 {
 		logger.Debug("Selecting columns: %v", options.Columns)
@@ -398,7 +413,7 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 	}
 
 	// Execute query - modelPtr was already created earlier
-	if err := query.Scan(ctx, modelPtr); err != nil {
+	if err := query.ScanModel(ctx); err != nil {
 		logger.Error("Error executing query: %v", err)
 		h.sendError(w, http.StatusInternalServerError, "query_error", "Error executing query", err)
 		return