Hello @Julian.Bai

The RD library supports 3 sessions (or access points) as follows:

• Desktop Session: Connect to the Workspace/Eikon desktop application that runs in the same machine using App Key (the same way as Eikon Data API)
• Platform Session: Connect to the RDP using RDP credential.
• Streaming services with a deployed ADS: Connect to local RTDS server.

The clients can configure which access point they want to connect via the RD - Lib configuration file.

{
    "logs": {
        "level": "debug",
        "transports": {
            "console": {
                "enabled": false
            },
            "file": {
                "enabled": false,
                "name": "refinitiv-data-lib.log"
            }
        }
    },
    "sessions": {
        "default": "platform.rdp",
        "platform": {
            "rdp": {
                "app-key": "YOUR APP KEY GOES HERE!",
                "username": "YOUR RDP LOGIN OR MACHINE GOES HERE!",
                "password": "YOUR RDP PASSWORD GOES HERE!"
            },
            "deployed": {
                "app-key": "YOUR APP KEY GOES HERE!",
                "realtime-distribution-system": {
                    "url" : "YOUR DEPLOYED HOST:PORT GOES HERE!",
                    "dacs" : {
                        "username" : "YOUR DACS ID GOES HERE!",
                        "application-id" : 256,
                        "position" : ""
                    }
                }
            }
        },
        "desktop": {
            "workspace": {
                "app-key": "YOUR APP KEY GOES HERE!"
            }
        }
    }
}

And the code uses

refinitiv.data as rd 
rdp.opensession()
rd.get_data(['LSEG.L', 'VOD.L'])
...

as usual.

Please find more detail on the following resources:

• RD - Lib Python: Quickstart
• LSEG’s Refinitiv Data Library for Python and its Configuration Process

Hello @Julian.Bai

Both Standalone Eikon Data API (https://pypi.org/project/eikon/ - import eikon as ek) and Refinitiv Data Library for Python - Eikon module (https://pypi.org/project/refinitiv-data/ - import refinitiv.dataplatform.eikon as ek) are LSEG official products.

The Refinitiv Data Library for Python (RD Lib - Python) just includes the Eikon Data API to its library as a sub-module, so they (standalone and sub-module) are the same.

Please be informed that there is no plan to end of life the standalone Eikon Data API, but the sub-module Eikon Data API will be removed from the RD Lib in the future release.

Existing clients who are using the Eikon Data API either standalone or sub-module should upgrade to the RD Lib - Python "Desktop session" which has the same kind of functionalities as Eikon Data API.

Conclusion:

1) will eikon package end of life?  ==> no plan. 
2) which one is the official, refinitiv.data or refinitiv.dataplatform.eikon?  ==> They are all official. 
3) should someone using eikon before migrated to new package? ==> They should upgrade to RD Lib - Python "Desktop session"

I hope this information helps.