domain: server
language: python
class Item class
Writes all updated, inserted, and deleted records from the item dataset to the database.
The apply method
checks whether the item is a detail, and if it is, returns (the master saves the details changes)
checks whether the item is in edit or insert state , and if so, posts the record
checks if the change log has changes, and if not, returns
triggers the on_before_apply event handler if one is defined for the item
if connection parameter is None the task
connect method is called to get a connection
from task connection pool
if on_apply event handler of the task is defined, executes it
if on_apply event handler is defined for the item, executes it
generates and executes SQL query to write changes to the database using the connection
if connection parameter was not specified, commits changes to the database and
returns connection to the connection pool
after writing changes to the database, updates the change log and the item dataset - updates primary key values of new records
triggers the on_after_apply event handler if one is defined for the item
connection - if this parameter is specified the appication uses it to
execute sql query that it generates (it doesn’t commit changes and doesn’t
close the connection), otherwise it procures a connection from the task connection
pool that will be returned to the pool after changes are commited.
params - use the parameter to pass some user defined options to be used in
the
on_apply
event handler. This parameter must be an object of key-value pairs
safe - if set to True, the method checks if the user that called the
method has a right to create, edit or delete records in the item’s database
table (if such operation is going to be performed) and, if not, raises
an exception. The default value is False.
See
Roles
In the second example below, the changes are saved in one transaction.
def change_invoice_date(item, item_id):
inv = item.copy()
cust = item.task.customers.copy()
inv.set_where(id=item_id)
inv.open()
if inv.record_count():
now = datetime.datetime.now()
cust.set_where(id=inv.customer.value)
cust.open()
inv.edit()
inv.invoice_datetime.value = now
inv.post()
inv.apply()
cust.edit()
cust.last_action_date.value = now
cust.post()
cust.apply()
def change_invoice_date(item, item_id):
con = item.task.connect()
try:
inv = item.copy()
cust = item.task.customers.copy()
inv.set_where(id=item_id)
inv.open()
if inv.record_count():
now = datetime.datetime.now()
cust.set_where(id=inv.customer.value)
cust.open()
inv.edit()
inv.invoice_datetime.value = now
inv.post()
inv.apply(con)
cust.edit()
cust.last_action_date.value = now
cust.post()
cust.apply(con)
finally:
con.commit()
con.close()