pagination optimization

pkg/mongo/repository.go

@@ -26,6 +26,8 @@ type Pagination struct {
 	Cursor    string `json:"cursor"`    // Base64 encoded cursor for cursor-based pagination
 	SortField string `json:"sortField"` // Field to sort by (default: "_id")
 	SortOrder int    `json:"sortOrder"` // Sort order: 1 for ascending, -1 for descending
+	// Projection limits fields returned from Find (e.g. exclude large blobs on list endpoints).
+	Projection bson.M `json:"projection,omitempty"`
 }
 
 // PaginatedResult represents a paginated result set
@@ -138,6 +140,10 @@ func (r *repository[T]) FindAll(ctx context.Context, filter bson.M, pagination P
 		SetSort(sort).
 		SetLimit(int64(pagination.Limit + 1)) // +1 to check if there are more documents
 
+	if len(pagination.Projection) > 0 {
+		findOptions.SetProjection(pagination.Projection)
+	}
+
 	// Handle cursor-based pagination
 	if pagination.Cursor != "" {
 		cursorFilter, err := r.buildCursorFilter(pagination.Cursor, pagination.SortField, pagination.SortOrder)
@@ -181,13 +187,14 @@ func (r *repository[T]) FindAll(ctx context.Context, filter bson.M, pagination P
 		items = items[:pagination.Limit] // Remove the extra item
 	}
 
-	// Get total count
-	totalCount, err := r.Count(ctx, filter)
-	if err != nil {
+	// Get total count for pagination metadata
+	var totalCount int64
+	var countErr error
+	totalCount, countErr = r.Count(ctx, filter)
+	if countErr != nil {
 		r.logger.Error("Failed to get total count", map[string]interface{}{
-			"error": err.Error(),
+			"error": countErr.Error(),
 		})
-		// Don't fail the entire query, just set count to 0
 		totalCount = 0
 	}