Sequence constraints of product feeds for Amazon MWS - amazon-web-services

Question

I am currently working on a specification for a software component which will synchronize the product catalog of an ecommerce company with the Amazon Marketplace using Amazon MWS.
According to the MWS developer documentation, publishing products requires submitting up to 6 different feeds, which are processed asynchronously:
Product Feed: defines SKUs and contains descriptive data for the products
Inventory Feed: sets quantities/availability for each SKU
Price Feed: sets prices for SKUs
Image Feed: product images for each SKU
Relationship Feed: defines mappings between parent SKUs (e.g. a T-Shirt) and child SKUs (e.g. T-Shirt in a concrete size and color which is buyable)
Ovverride Feed:
My question concerns the following passage in the MWS documentation:
The Product feed is the first step in setting up your products on
Amazon. All subsequent catalog feeds are dependent upon the success of
this feed.
I am wondering what it means? There are at least two possibilities:
Do you have to wait until the Product feed is successfully processed before submitting subsequent feeds? This would mean that one had to request the processing state periodically until it is finished. This may take hours depending of the feed size and server load at Amazon. The process of synchronizing products would be more complex.
Can you send all the feeds immediately in one sequence and Amazon takes care that they are processed in a reasonable order? In this interpretation, the documentation would just tell the obvious, that the success of let's say image feed processing for a particular SKU depends on the success of inserting the SKU itself.

Answer 1

As I understand it for all other feeds other than the Product feed the products in question must already be on the catalogue, so your first possibility is the correct one.
However, this should only affect you on the very first run of the product feed or when you are adding a new product, as once the product is there you can then run the feeds in any order, unless you are using PurgeAndReplace of your entire catalogue each time which is not recommended.
The way I would plan it is this.
1) Run a Product Feed of the entire catalogue the very first time and wait for it to complete.
2) Run the other feeds in any order you like.
3) Changes to any of the products already on Amazon can now be done in any order. e.g you can run the price feed before the product feed if all you are doing is amending the description data etc
4) When you have to add a new product make sure you run the product feed first, then the other feeds.
If possible, I would create a separate process for adding new products. Also, I think it will help you if you only upload changes to products rather than the entire catalogue each time. It's a bit more work for you to determine what has changed but it will speed up the feed process and mean you're not always waiting for the product feed to complete.

Answer 2

Yes, Product Feed is the first primary feed.
You need to wait until product feed gets completed before sending out other feeds.
When You Send Product Feed, its status becomes:
1) _IN_PROGRESS_
2) SUBMITTED
3) DONE
4) COMPLETED
You must need to wait until status changes to " DONE " or "COMPLETED".
Thanks.