SAP PO Java Single Stack - need a tutorial for creating an API for getting PO messages payload

[nacnick]

Dear SAP Community!

There is a need in my team for creating a monitoring system for SAP PO messages besides SAP default pimon.
In order to do that we want to extract the messages payload with the help of an API.
After an internet research we saw that there is the "Web Services Navigator" tool which consists of different operations such as "getMessageList", "getMessageBytesJavaLangStringBoolean" and a lot others.
It seems that with the help of this tool we get what we are looking for.
Now we want to implement an API (REST API is preferred) that will get us the messages payload.
We would love for a tutorial and detailed explaination of how we can implement this sort of API (REST API is preferred) with the help of the "Web Services Navigator" tool mentioned above, ESR, IB or other useful tools you might know of.

**If there is a way to extract SAP PO messages information and payloads with python language without any other tools - it is our most preferable way 🙂

P.S. We already have of course ESR, IB and SAP PO Java single stack.
We use SAP NetWeaver Process Integration 7.50.

Thank you in advance!!