Specify the User under which a Python Program Runs

The Python Program tab on the configuration form of a Python Program includes a User field. You use the field to specify the name of the User Account under which the Python program is to run. This has to be a valid User Account in Geo SCADA Expert. The User Account determines the level of access that the Python program has to any database items that it references and to any database methods that it calls.

Use the browse button to display a Reference browse window and then select the required entry from the window.

We strongly recommend that you specify a suitable 'configured' User Account in this field. If the field is left blank, the program will attempt to run under the Guest User account (if enabled on your system). The Guest User account typically has no permissions by default and so the program is unlikely to run to completion successfully.

You can only successfully specify a User Account in this field if you have the relevant permissions for that User Account (see Permissions for Database Items in the Geo SCADA Expert Guide to Security). If you do not, Geo SCADA Expert will discard this particular configuration change when you attempt to save the change. If this occurs, the field will revert back to its previously stored value.

The User Account under which the Python program runs has to have the relevant level of access to any database items that the Python program references. This includes access to the hierarchy of Groups within which those database items are nested in the database. Be aware that if the database items are in a Group Instance and inherit some of their settings from a Group Template, the User Account also requires the relevant access to, and permissions for, that Group Template. There are special cases for some types of database item, such as security-related database items. For more information, see Permissions for Database Items in the Geo SCADA Expert Guide to Security.

The Database Schema lists the Read and Write privileges that a User Account requires to access the data and configuration fields of the various items ('objects') in the database. The Database Schema also lists the permissions that are required to execute the methods that are associated with those database items. Be aware that in some cases, the Security permission might also be required to write to configuration fields on some database items. Also see the 'Considerations and Special Cases' section in Permissions for Database Items in the Geo SCADA Expert Guide to Security.

If the Python program is configured to execute due to the 'On Object Change' trigger condition, the User Account under which the Python program runs only requires access to that database item if it is referenced in the Python program code.