From a32753a04afea703e23479f671c27c12de8cfe55 Mon Sep 17 00:00:00 2001
From: Lance Edgar <lance@edbob.org>
Date: Thu, 9 Jul 2020 17:01:23 -0500
Subject: [PATCH] Let CORE-POS datasync watcher use alternate "changes" table
 name

i needed this for sake of online demo, so that 2 separate rattail apps could
both watch the same CORE DB simultaneously
---
 rattail_corepos/datasync/corepos.py | 29 +++++++++++++++++++++++------
 1 file changed, 23 insertions(+), 6 deletions(-)

diff --git a/rattail_corepos/datasync/corepos.py b/rattail_corepos/datasync/corepos.py
index d335384..3bebaf3 100644
--- a/rattail_corepos/datasync/corepos.py
+++ b/rattail_corepos/datasync/corepos.py
@@ -24,6 +24,8 @@
 DataSync for CORE POS
 """
 
+import sqlalchemy as sa
+
 from corepos.db.office_op import Session as CoreSession, model as corepos
 
 from rattail.db import model
@@ -36,10 +38,24 @@ class CoreOfficeOpWatcher(DataSyncWatcher):
     """
     prunes_changes = True
 
+    def __init__(self, *args, **kwargs):
+        super(CoreOfficeOpWatcher, self).__init__(*args, **kwargs)
+
+        self.changes_table_name = kwargs.get('changes_table_name',
+                                             'datasync_changes')
+
+        self.corepos_metadata = sa.MetaData()
+        self.corepos_changes = sa.Table(
+            self.changes_table_name, self.corepos_metadata,
+            sa.Column('id', sa.Integer(), nullable=False, primary_key=True),
+            sa.Column('object_type', sa.String(length=255), nullable=False),
+            sa.Column('object_key', sa.String(length=255), nullable=False),
+            sa.Column('deleted', sa.Boolean(), nullable=False, default=False))
+
     def get_changes(self, lastrun):
         session = CoreSession()
-        changes = session.query(corepos.Change).all()
-        session.expunge_all()
+        result = session.execute(sa.sql.select([self.corepos_changes]))
+        changes = result.fetchall()
         session.close()
         if changes:
             return [
@@ -54,10 +70,11 @@ class CoreOfficeOpWatcher(DataSyncWatcher):
         deleted = 0
         session = CoreSession()
         for key in keys:
-            change = session.query(corepos.Change).get(key)
-            if change:
-                session.delete(change)
-                session.flush()
+            result = session.execute(self.corepos_changes.select()\
+                                     .where(self.corepos_changes.c.id == key))
+            if result.fetchall():
+                session.execute(self.corepos_changes.delete()\
+                                .where(self.corepos_changes.c.id == key))
                 deleted += 1
         session.commit()
         session.close()