Signaling the Data Source that has a problem

[Limraj]

Expected Behavior If the Data Source is having script executing/connections problems, this should be visible to the user in watchlists and graphical views.

To reproduce

1. Login as admin;
2. Create Virtual Data Source as virtual_ds (enabled, update: 1s) and Virtual Data Point as virtual_dp_1 (enabled, numeric, random, min:0, max:123, start value:0) and virtual_dp_2 (enabled, settable, binary, no change, start value:0)
3. Create Meta Data Source as meta_ds (enabled) and Meta Data Point as meta_dp (enabled, numeric) Added to context: p1 - 'virtual_ds - virtual_dp_1'; p2 - 'virtual_ds - virtual_dp_2'; and set script: if(p2.value) return p1.value; return -1;
4. Added to watchlist as wl_1, add added points: a) 'meta_ds - meta_dp'; b) 'virtual_ds - virtual_dp_1'; c) 'virtual_ds - virtual_dp_2';
5. Disabled virtual_ds;
6. meta_dp does not change and does not indicate a problem -> ERROR 1;
7. Enabled virtaul ds -> meta_ds meta_dp value changes as expected;
8. Deleted 'virtual_ds - virtual_dp_1' -> identical behavior as in step 7, meta_dp does not indicate a problem -> ERROR 2;

To do It is worth adding such signaling at least in:

• [x] Meta Data Source
• [x] Modbus IP
• [x] SNMP
• [x] HTTP Retriever
• [x] SQL
• [x] MQTT
• [x] Internal Data Source
• [x] Virtual Data Source
• [x] JMX
• [x] Modbus Serial
• [x] 1-wire
• [x] BACnet I/P
• [x] DNP3 IP
• [x] DNP3 Serial
• [x] AMQP
• [x] ASCII File Reader
• [x] ASCII Serial
• [x] Dr.Storage HT-5B
• [x] Galil DMC-21x2
• [x] HTTP Image
• [x] HTTP Receiver
• [x] IEC101 Ethernet
• [x] IEC101 Serial
• [x] M Bus
• [x] Mitsubishi Alpha2
• [x] NMEA listener
• [x] OPC DA
• [x] OpenV4J
• [x] Pachube
• [x] POP3 Email
• [x] Serotonin Persistent TCP
• [x] VMStat Data Source

You can follow the solution included in Data Source MQTT/AMQP;

Specifications Scada-LTS Version: 2.6.18

Linked: #1745