Set Up Authentication for the Coupa Supplier Portal REST API

1. Create an OAuth 2.0 client and assign scopes.
   1. Navigate to Setup > Admin .
   2. Select API Clients and select Create.
   3. Define these fields.

      Field	Description
      Name	Enter an API client name.
      Hostname	Supplier client application hostname.
      Scopes	Select csp.invoices.read.

   1. Select Save.
      The API Client Details page displays. Note the Identifier and Secret fields to use in your API call to generate the token in the following step.
2. Send an API call to generate a token.
   1. Send a POST call to https://<your-instance>.supplier.com/oauth2/token.

      Include these elements in the request body.

      Element	Description
      client_id	Client identifier value from the OAuth 2.0 client.
      client_secret	Client secret value from the OAuth 2.0 client.
      grant_type	Enter client_credentials.
      scopes	List of scopes with commas removed.

      Example cURL request:

      curl --location 'https://<your-instance>.supplier.coupahost.com/oauth2/token' \
      --header 'Content-Type: application/x-www-form-urlencoded' \
      --data-urlencode 'client_id=3c1ce11a8105004359a7e00b7c4cfd09' \
      --data-urlencode 'grant_type=client_credentials' \
      --data-urlencode 'scope=csp.invoices.read' \
      --data-urlencode 'client_secret=4cef98122f7adcd701585789808a49714bd116a6fed5cdfe7e1c84f5e6377fb1'
      

The API returns a bearer token to use in subsequent API calls.