if you insist on that line you need

Set Jsonobj="{""Doctype"":""ADT^A01"",""PatientId"":""123"",""PatientName"":""Alex""}"

by using {}  your Jsonobj is already a  %Library.DynamicObject
Jsonobj=<OBJECT REFERENCE>[1@%Library.DynamicObject]

no need for 
Set Dynjsonobj=##class(%Library.DynamicObject).%FromJSON(Jsonobj)

You are correct it is working inside docker in the container.
But I asked for the external real IP of my (Windows) Host.
I know that is wrong for my purpose,  as I sit just in front of it
and use it some 100 times daily. So I really know it.

It's an odd situation: IRIS -> Ubuntu in container -> Docker -> WSL -> Windows.
I didn't add NAT and Port mapping used by Windows. 

I did the test, but it failed.

C:\GitHub\_my\SSH-for-IRIS-container>docker-compose exec iris iris session iris

Node: f386a88482f2, Instance: IRIS
USER>Set ip = $SYSTEM.INetInfo.HostNameToAddr("host.docker.internal")
USER>zw ip

The correct IP =
it's also not the IP-Address of WSL-2 shell
It's not even in the DHCP range of my router, nor in the WLAN range

BUT: this is an excellent use case for my recent Proposal

Hi @Iryna Mykhailova and welcome to the Tutorials Contest.
I was waiting for you.
I feel honored that you took the same subject as me %QUERY (officially  Class Query)
In addition, I appreciate that you confirmed by your screenshots, my statement that
the Studio wizard is the most comfortable way to start with the subject. 

The idea to simulate a virtual table is a very nice idea. 
But there is a point in your example that I don't understand:

  • ClassMethod GetAllOlderThanExecute(ByRef qHandle As %Binary, Age As %Integer = 65)  
  • But in ClassMethod GetAllOlderThanFetch(.....)  you don't have it anymore and don't use it and display ALL generated records independent of Age

Did I miss something? 

I found an acceptable workaround.

  • installed telnetd into the container and started it
  • mapped some external port to port 23
  • set this external port  in my cube
  • started the IRIS Terminal
  • BINGO !

You may raise all concerns on Security and Container Isolation.  Accepted! And ignored!
Since THIS solves my issues on optical verification of the user interface.