- def sync(self, commit = True):
- """
- Flush changes back to the database.
- """
-
- try:
- if not self['name']:
- raise KeyError
- except KeyError:
- raise PLCInvalidArgument, "Slice name must be specified"
-
- self.validate()
-
- # Fetch a new slice_id if necessary
- if 'slice_id' not in self:
- # N.B.: Responsibility of the caller to ensure that
- # max_slices is not exceeded.
- rows = self.api.db.selectall("SELECT NEXTVAL('slices_slice_id_seq') AS slice_id")
- if not rows:
- raise PLCDBError, "Unable to fetch new slice_id"
- self['slice_id'] = rows[0]['slice_id']
- insert = True
- else:
- insert = False
-
- # Filter out fields that cannot be set or updated directly
- slices_fields = self.api.db.fields('slices')
- fields = dict(filter(lambda (key, value): \
- key in slices_fields and \
- (key not in self.fields or not self.fields[key].ro),
- self.items()))
-
- # Parameterize for safety
- keys = fields.keys()
- values = [self.api.db.param(key, value) for (key, value) in fields.items()]
-
- if insert:
- # Insert new row in slices table
- sql = "INSERT INTO slices (%s) VALUES (%s)" % \
- (", ".join(keys), ", ".join(values))
- else:
- # Update existing row in slices table
- columns = ["%s = %s" % (key, value) for (key, value) in zip(keys, values)]
- sql = "UPDATE slices SET " + \
- ", ".join(columns) + \
- " WHERE slice_id = %(slice_id)d"
-
- self.api.db.do(sql, fields)
-
- if commit:
- self.api.db.commit()
-