Update my product database with json file

Hi, I’m looking for an alternative way to update my product database. So I’ve multiple suppliers and they send me a list of new (or old product with modified price for example) products. They send me a json file, and I have to update it to my product database. Each product have an unique reference (but 2 items can have the same reference but different suppliers). And I’m looking for a way to update my database with a given json file.
Normally what I do is : I pull the csv list of products from shopify, transform the json file into excel file, and add it to the csv file (with some condition like if there are changes in an existed product it will change itself) and then reupload it on shopify.
Is there an alternative way? I want to optimize it because it takes time for me to do it.
Thank you so much