RE: How to place an order in NetSuite from 3rd party platform through NetSuite API(Rest or SOAP)?
We utilize REST to create orders in NetSuite. It was quite a lot of compiling information from multiple different sources.
We settled on using Oauth 2.0. Here is a good starting point for registering your application to authorize via Oauth 2.0: https://docs.oracle.com/en/cloud/saas/netsuite/ns-online-help/chapter_157769826287.html
NetSuite doesn’t have a true swagger document. Their documentation on this is very limited with poor examples. I utilized a GET on a sample sales order to help create the JSON payload for our orders. Here is their documentation: https://system.netsuite.com/help/helpcenter/en_US/APIs/REST_API_Browser/record/v1/2021.2/index.html#tag-salesOrder
I will note, there are some fields that we had to set via a workflow because the API route wasn’t working. NetSuite’s API’s seem to be missing quite a bit of functionality. It would be awesome if they supplied more examples.