How can I link a contact to a opportunity via REST API?

Question

I'm trying to find some documentation on how to do this. I will start trying to use this endpoint now, but its not clear to me if it will work: 
 <module>/:record/link/:link_name/:remote_id POST 
 But I do not know if it will work. 
 
 Thanks for some help.

Mark Deraeve · Accepted Answer

Good morning Marc. 
 You are on the right track, that is the API to link two records. If you look at the Opportunities Vardefs in your cache folder: 
 cache/modules/Opportunities/Opportunityvardefs.php 
 and search for "Contacts" you will find the definition of the link, there you will see that the link name is "contacts" (not to be confused with the relationship name which is "opportunities_contacts") 
 So, once you have identified the link name, the opportunity id, and the contact id, you can easily link the two with that API. 
 say your 
 opportunity id = 60f2b566-30b5-11ea-8ef6-001a4a160206 
 
 contact id = ec740bd4-fbca-11e7-8ee2-001a4a160206 
 Your API call to link Contact to Opportunity: 
 
 Opportunities/ 60f2b566-30b5-11ea-8ef6-001a4a160206 /link/contacts/ ec740bd4-fbca-11e7-8ee2-001a4a160206 
 
 You could do the same starting from the Contacts module, look up the link name for Opportunities in the Contacts cache file: 
 cache/modules/Contacts/ Contactvardefs.php 
 Identify the name of the link which is "opportunities" 
 And build the API call from the Contacts: 
 opportunity id = 60f2b566-30b5-11ea-8ef6-001a4a160206 
 contact id = ec740bd4-fbca-11e7-8ee2-001a4a160206 
 Your API call to link the Opportunity to the Contact: 
 Contacts/ ec740bd4-fbca-11e7-8ee2-001a4a160206/link/opportunities/60f2b566-30b5-11ea-8ef6-001a4a160206 
 
 Hope this helps clarify that Rest API. 
 FrancescaS