On hEDD service 244, we saw a "suspect" status with code "Already_open" for all of our subscriptions at several times the week of 10 September 2018. For example, at 15:50:28.548690-04:00 on 2018-09-11, we logged the following on the symbol USFN3050=TWEB:
((domain_type Market_price) (class_data ( Status ( (perm_data ()) (post_user_info ()) (extended_header ()) (msg_key (( (service_id (467)) (name_type (Ric)) (name ((USFN3050=TWEB))) (filter ()) (identifier ()) (attrib ())))) (req_msg_key ()) (state (( (code Already_open) (text ("Item was reopened under new stream.")) (data_state Suspect) (stream_state Closed)))) (group_id ()) (flags ())))) (contents No_data))
What is the cause of this issue? We do not typically see it, and we don't believe we were doing anything different with those subscriptions during that week.
This message occurs if you have a subscription open for a specific Item within a given Service and domain and you try to open the exact same item as a new subscription. The server will detect that for your session, you are already watching this item and will close the existing one and open (reopen) the new request you made. The server is simply ensuring that if you already are watching this item that you don't need multiple copies of the same updates.
Your application needs to ensure that you either close out the existing open stream or determine if you already have the same one open before you make the request.