How to Restrict Communication User to Read-Only Access in SAP_COM_0009 Without Using SAP BTP APIM

I person a request for a 3rd Party institution to entree our data.

For example;I americium utilizing the SAP_COM_0009 connection statement successful SAP S/4HANA Public Cloud to let speechmaking and instauration of products. The statement is configured with a connection strategy and connection user.

I privation to restrict the connection idiosyncratic to lone read access (i.e., let lone GET operations and artifact POST, PUT, and DELETE). However, I cannot find a straightforward mode to configure this restriction.

Here’s what I’ve tried truthful far:

1. Checked the Maintain Communication Users app but recovered nary enactment to nexus oregon set concern roles for connection users.
2. Explored the Maintain Business Roles app to find roles oregon catalogs associated with the connection idiosyncratic but couldn't place immoderate nonstop link.
3. Attempted to modify the scope of the connection statement itself, but determination seems to beryllium nary configurable enactment to enforce read-only permissions.

Critical Note:
While I recognize that SAP BTP API Management (APIM) could supply a mode to restrict operations astatine the API level, I bash not privation to impact SAP BTP APIM owed to:

1. Additional overhead successful configuration and maintenance.
2. The penchant to support the setup afloat wrong SAP S/4HANA Cloud for simplicity and to debar reliance connected BTP.

Could idiosyncratic clarify:

• How to configure a connection idiosyncratic for read-only entree successful SAP_COM_0009 wrong the boundaries of S/4HANA Cloud?
• Is it imaginable to set the scope of operations (e.g., GET only) for this connection arrangement?

Any guidance oregon alternate approaches would beryllium greatly appreciated. Thank you!