UI should validate saved column state against available columns

[heswell]

The UI saves state for Table components. This includes any changes to properties made by user, e.g

• apply sort
• apply filter(s)
• re-arrange columns
• hide column(s)
• resize column(s)

IN the case of any change to any property the full table state is saved. This includes the list of columnNames

In the event that columns are removed from a Viewport on the Vuu server, this saved state may become invalid - it may continue to reference a column that no longer exists. In this scenario, a CREATE_VP request would fail because of the non-existent column included in request.

solution

1. Validate column names in saved state before issuing CREATE_VP message.

Note: state may include calculated column expressions. To validate these, the expressions must be parsed and any column references validated against the server TABLE_META.

2. Notify the user that a column has been removed IF

• there was a calculated column that referenced the removed column
• they have applied some changes to the column state

3. When we save datasource state (which is the state structure that includes the above), we should be more selective about what we save. We do not need to include the column definitions, for example, if these have not changed. If user just applied a sort, we can save just sortCriteria etc