Accessing API When OTCS is Using Single Sign On

I hope that somebody else will chime in, because I did not use this exact scenario myself.

OAuth is provided by OTDS, not CS. When you have the OAuth authentication token, you can use it to connect to the OTDS REST API and have it generate an OTDSTicket, which will be accepted by CS and can be exchanged to OTCSTicket by the very first call to the CS REST API.

I used OTDS REST API to get a ticket for CS + impersonation:

POST /otdsws/rest/authentication/resource/ticketforuser
{
  targetResourceId: "42B810FA-6F36-64CA-58EC-70AE1EF050E0",
  userName: "myuser",
  ticket: "OTDS SSO ticket"
}

If you ignore the impersonation and use your token instead of my ticket, you will just need to find the proper resource path. I cannot find the OTDS REST API on developer.opentext.com any more.

I found the OTDS REST API documentation for authentication. You must not search for "OTDS" to be able to find it :-)

If you struggle getting the CS Resource ID dynamically, here we are a couple of CS URLs from OTDSINTEGRATION, which need no authentication and return JSON output:

?func=otdsintegration.getloginurl
?func=otdsintegration.getresourceid
?func=otdsintegration.getserverurl

Another thing occurred to me: if you get the SSO token from the OTDS REST API instead of the resource-specific one, you will need no CS resource ID. That token works just once by default and you will have to save the OTCSTicket from the first CS response. But you should do it anyway for the optimal performance and to prevent user session exhaustion.