In order to interact with the UPCDatabase API, you or your application must authenticate. The UPCDatabase API handles this through OAuth, an open standard for authorization.
You can generate an OAuth token by visiting the API Keys section of your account.
An OAuth token functions as a complete authentication request. In effect, it acts as a substitute for a username and password pair.
The UPC Database API can accept authentication in one of two ways.
In order to make an authenticated request, include a bearer-type Authorization header containing your OAuth token. All requests must be made over HTTPS.
curl --location --request GET 'https://api.upcdatabase.org/product/0111222333446' \ --header 'Authorization: Bearer THISISALIVEDEMOAPIKEY19651D54X47'
You can also append your API key to the end of the query. This method is not OAuth compliant and should not be used.