cqle: refactor transactions to base CQL statement

cassandra/cqlengine/statements.py

@@ -471,7 +471,7 @@ class MapDeleteClause(BaseDeleteClause):
 class BaseCQLStatement(UnicodeMixin):
     """ The base cql statement class """
 
-    def __init__(self, table, consistency=None, timestamp=None, where=None, fetch_size=None):
+    def __init__(self, table, consistency=None, timestamp=None, where=None, fetch_size=None, transactions=None):
         super(BaseCQLStatement, self).__init__()
         self.table = table
         self.consistency = consistency
@@ -484,6 +484,10 @@ class BaseCQLStatement(UnicodeMixin):
         for clause in where or []:
             self.add_where_clause(clause)
 
+        self.transactions = []
+        for transaction in transactions or []:
+            self.add_transaction_clause(transaction)
+
     def add_where_clause(self, clause):
         """
         adds a where clause to this statement
@@ -506,6 +510,22 @@ class BaseCQLStatement(UnicodeMixin):
             clause.update_context(ctx)
         return ctx
 
+    def add_transaction_clause(self, clause):
+        """
+        Adds a iff clause to this statement
+
+        :param clause: The clause that will be added to the iff statement
+        :type clause: TransactionClause
+        """
+        if not isinstance(clause, TransactionClause):
+            raise StatementException('only instances of AssignmentClause can be added to statements')
+        clause.set_context_id(self.context_counter)
+        self.context_counter += clause.get_context_size()
+        self.transactions.append(clause)
+
+    def _get_transactions(self):
+        return 'IF {0}'.format(' AND '.join([six.text_type(c) for c in self.transactions]))
+
     def get_context_size(self):
         return len(self.get_context())
 
@@ -616,11 +636,13 @@ class AssignmentStatement(BaseCQLStatement):
                  consistency=None,
                  where=None,
                  ttl=None,
-                 timestamp=None):
+                 timestamp=None,
+                 transactions=None):
         super(AssignmentStatement, self).__init__(
             table,
             consistency=consistency,
             where=where,
+            transactions=transactions
         )
         self.ttl = ttl
         self.timestamp = timestamp
@@ -722,12 +744,8 @@ class UpdateStatement(AssignmentStatement):
                                                consistency=consistency,
                                                where=where,
                                                ttl=ttl,
-                                               timestamp=timestamp)
-
-        # Add iff statements
-        self.transactions = []
-        for transaction in transactions or []:
-            self.add_transaction_clause(transaction)
+                                               timestamp=timestamp,
+                                               transactions=transactions)
 
         self.if_exists = if_exists
 
@@ -759,28 +777,12 @@ class UpdateStatement(AssignmentStatement):
 
         return ' '.join(qs)
 
-    def add_transaction_clause(self, clause):
-        """
-        Adds a iff clause to this statement
-
-        :param clause: The clause that will be added to the iff statement
-        :type clause: TransactionClause
-        """
-        if not isinstance(clause, TransactionClause):
-            raise StatementException('only instances of AssignmentClause can be added to statements')
-        clause.set_context_id(self.context_counter)
-        self.context_counter += clause.get_context_size()
-        self.transactions.append(clause)
-
     def get_context(self):
         ctx = super(UpdateStatement, self).get_context()
         for clause in self.transactions or []:
             clause.update_context(ctx)
         return ctx
 
-    def _get_transactions(self):
-        return 'IF {0}'.format(' AND '.join([six.text_type(c) for c in self.transactions]))
-
     def update_context_id(self, i):
         super(UpdateStatement, self).update_context_id(i)
         for transaction in self.transactions:
@@ -796,7 +798,8 @@ class DeleteStatement(BaseCQLStatement):
             table,
             consistency=consistency,
             where=where,
-            timestamp=timestamp
+            timestamp=timestamp,
+            transactions=transactions
         )
         self.fields = []
         if isinstance(fields, six.string_types):
@@ -804,10 +807,6 @@ class DeleteStatement(BaseCQLStatement):
         for field in fields or []:
             self.add_field(field)
 
-        self.transactions = []
-        for transaction in transactions or []:
-            self.add_transaction_clause(transaction)
-
         self.if_exists = if_exists
 
     def update_context_id(self, i):
@@ -833,22 +832,6 @@ class DeleteStatement(BaseCQLStatement):
         self.context_counter += field.get_context_size()
         self.fields.append(field)
 
-    def add_transaction_clause(self, clause):
-        """
-        Adds a iff clause to this statement
-
-        :param clause: The clause that will be added to the iff statement
-        :type clause: TransactionClause
-        """
-        if not isinstance(clause, TransactionClause):
-            raise StatementException('only instances of AssignmentClause can be added to statements')
-        clause.set_context_id(self.context_counter)
-        self.context_counter += clause.get_context_size()
-        self.transactions.append(clause)
-
-    def _get_transactions(self):
-        return 'IF {0}'.format(' AND '.join([six.text_type(c) for c in self.transactions]))
-
     def __unicode__(self):
         qs = ['DELETE']
         if self.fields: