EMA: hasPermissionData() on item for refresh/update message

DimAngelNX

Hi,

Inside OnRefreshMsge() and OnUpdateMsg() I check if item has permission data by calling

message.hasPermissionData().

For the same item hasPermissionData() gives me TRUE if i'm inside a Refresh Message and FALSE if i'm inside an Update Message.

Is it normal? I'm struggling to understand why?

Thank you

umer.nalla

Hi @DimAngelNX

As far as I am aware you only see Permission Data in a RefreshMsg - as the data applies to a particular Permissionable Entity and the permission data rarely changes for the instrument - so it makes no sense (from a permission-checking or bandwidth-usage point of view) to keep repeating the same bit of data.

Assuming that you are doing some sort of proxy permissions checks - you would check the permissions when a user first makes a request for an instrument - if they are permssioned, they can then be provided with the Refresh values and any subsequent updates.

If for some reason the permission data does change, you would receive another (unsolicited) Refresh for the same instrument with the revised permission data.