DrByte:
Are you sure that you REALLY want to use an API to load prices IN REAL TIME?
EVERY price that is displayed in Zen Cart will have to be requested separately for EVERY place ANY price is displayed on the screen, OR used in a calculation to come up with EVERY number displayed on the screen.
If you've got a very busy site, then you'll be brokering thousands of inquiries per second, effectively blasting their API server. That's very inefficient and will likely result in a very slow experience for your customer. Not to mention the technical problems it'll create for the people who run the API server.
It's much more efficient for you to run an API call, even if it's every 10 minutes, to request all the updated prices for all the products, ideally in one request if possible, and update all your store's prices accordingly. That's way more friendly to the folks who run the API server, and it's a much better experience for your customers.
The original idea was to use a cronjob and hosted database that would have all our products, the pricing would be updates every 2-5 minutes using xignite metals data feed, our hosted service would take the price of metals and calculate product prices and then the software would push the product prices to zencart database every 2-5 minutes,
Now, the developer is changing the way they like to impalement this, the hosted service is their product but now need to hook it up to zencart, I was also surprised of the change because I talked to few other people and everyone was agreed that a cronjob would be used and a hosted database with updating zencart database at a scheduled interval.
I don't think they are familiar the way zencart works, they think it's a simple few line of code.
I appreciate your input,