Create OAuth communication system and user

Navigate to Communication Systems tile to start the application.

Create a new communication system by clicking New.

By adding a system ID, system name and clicking Create, you are able to register a new communication system.

Switch back to your SAP Cloud Platform cockpit, go to Services and select SAP Web IDE. Copy the link address of Go to Service. This will be needed in the creation process of the communication system.

Add your host name. This information can be found on SAP Cloud Platform. It corresponds to the link address copied from Step 4 of this tutorial.

Click + to add a user for inbound communication. Inbound communication means that the here defined system is used from a communication partner to call from external into the S/4HANA system. Doing this, the user that will be added next has to be used to get authorized.

Click New User to create one.

Enter a user name and description for your user. Give your user a password and click Create.

The new user will be generated by clicking OK.

Switch to your SAP Cloud Platform subaccount. Open trust settings and download the metadata by clicking Get Metadata. Also copy the local provider name for later use.

Take your downloaded metadata file from SAP Cloud Platform and open it with an editor of your choice.

1. Copy the code between both tags in another file.
   
2. Add also the begin and end tag to your copied code:

         -----BEGIN CERTIFICATE-----
              your_copied_code
         -----END CERTIFICATE-----
   
   

3. Save your changes as .cer file.

Go back to your SAP S/4HANA Cloud system and open your created communication system draft. Edit your draft and enable it for OAuth 2.0 by checking the enabled box. Then upload the certificate by clicking upload signing certificate. Enter the provider name, which is the subaccount’s local service provider’s name. You copied it a few steps before. Click Save.

With this step, you’ve uploaded your certificate to your communication system. Now your S/4HANA system trusts your SAP Cloud Platform subaccount.