book: add caching for line

book.py

@@ -15,7 +15,7 @@ from datetime import date
 from sql.aggregate import Sum
 from sql.conditionals import Case
 from .model import order_name_hierarchical, sub_ids_hierarchical, \
-    AnyInArray, CACHEKEY_CURRENCY
+    AnyInArray, CACHEKEY_CURRENCY, CACHEKEY_CASHBOOK
 
 
 STATES = {
@@ -262,6 +262,16 @@ class Book(tree(separator='/'), Workflow, ModelSQL, ModelView):
                 }
         return recname
 
+    def get_cachekeys_by_hierarchy(self):
+        """ generate keys for all cashbooks above us
+        """
+        CBook = Pool().get('cashbook.book')
+
+        return [CACHEKEY_CASHBOOK % x.id
+            for x in CBook.search([
+                    ('parent', 'parent_of', [self.id]),
+                ], order=[('id', 'ASC')])]
+
     @classmethod
     def get_balance_of_cashbook_sql(cls):
         """ sql for balance of a single cashbook
@@ -371,6 +381,7 @@ class Book(tree(separator='/'), Workflow, ModelSQL, ModelView):
                     query = [{
                             'model': 'cashbook.line',
                             'query': [('cashbook.parent', 'child_of', [x.id])],
+                            'cachekey': CACHEKEY_CASHBOOK % x.id,
                         }, {
                             'model': 'currency.currency.rate',
                             'query': [('currency.id', '=', x.currency.id)],