Deleting historical data points from a OPCUA server using asyncua

[KishanKishore]

The asyncua library currently has methods to read historical data from an OPCUA server.

1. According to the OPCUA specification the server can have the following capability. More on this here

The DeleteAtTimeCapability Variable indicates support for the delete at time capability. A value of True indicates the Server supports the capability to delete a data value at a specified time. The default value is False.

2. Does the asyncua client support the deletion of history from an OPCUA server ?
3. Is there a way we can fetch the range of historical data present in an OPCUA server using asyncua?

[AndreasHeine]

Does the asyncua client support the deletion of history from an OPCUA server ?

https://reference.opcfoundation.org/v104/Core/docs/Part4/5.10.5/

5.10.5 HistoryUpdate:

there is currently no method in uaclient.py
https://github.com/FreeOpcUa/opcua-asyncio/blob/master/asyncua/client/ua_client.py

but all lowlevel classes are avalible to make a request:

opcua-asyncio/asyncua/ua/uaprotocol_auto.py

Line 6265 in 398a45c

class HistoryUpdateParameters:

opcua-asyncio/asyncua/ua/uaprotocol_auto.py

Line 6275 in 398a45c

class HistoryUpdateRequest:

if you have a server which supports that feature you could make a PR to add that feature to the uaclient.py / client.py!

is not implemented in asyncua-server!
all currently supported requesttypesof the server:

opcua-asyncio/asyncua/server/uaprocessor.py

Line 150 in 398a45c

async def _process_message(self, typeid, requesthdr, seqhdr, body):

Is there a way we can fetch the range of historical data present in an OPCUA server using asyncua?

the high level client (client.py) no!
the low level client (ua.client.py) yes!

opcua-asyncio/asyncua/client/ua_client.py

Line 619 in 398a45c

async def history_read(self, params):

[KishanKishore]

Thanks for the response. I will have a look at these classes/methods.