How to setup the Magento 2 API Permissions?

It is important to setup the Magento API permissions and Optiply permissions to have a working integration. Several steps are needed, which are listed below.

1. Go to the Admin backoffice, System > Integrations
   
   
   

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2. Edit the Integration already created and used to send credentials
   
   
   

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3. On Basic Settings > API, set
   Resource Access -  All (for everything)
   or Custom (for individually choose permissions by resource)
   
   
   

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4. For a Custom setup, we should have at least:
   Orders (Sales)

   Products (Catalog)

   stockStatus (Stores > Settings > Configuration > Inventory Section)