Getting all items on Amazon Product API - php

Question

Amazon's Product API limits us to get only 10 items per page, and only 10 pages at a certain query.
I have developed a code that would almost get all items;
first, I have supplied a params that looks like this:
$item_params = [
"Service" => "AWSECommerceService",
"Operation" => "ItemSearch",
"AWSAccessKeyId" => env('AWS_ACCESS_KEY_ID'),
"AssociateTag" => env('AWS_ASSOCIATE_TAG_ID'),
"SearchIndex" => "HomeGarden",
"ResponseGroup" => "ItemAttributes,SalesRank,Offers",
"Sort" => "-price",
"BrowseNode" => $item_params['BrowseNode'],
"MaximumPrice" => $max_price,
"MinimumPrice" => "0"
];
then, the code will get all items under that browse node (category), SORTED BY PRICE (desc) also by specifying the MAX and MIN Price of the items to limit the search.
the pseudo-code (original code is too long)
function getProducts($item_params, $max_price = null){
$products = //request to amazon
foreach ($product as $key=>$value){
//add product to db
}
// if the total number of results on the query is not equal to zero, continue looping
if (!$products->totalResults() == 0){
$product = //get the first lowest priced item on the db
$this->getProducts($item_params, $product->price);
}
}
however I am experiencing this scenario :
Sample request output (assuming all items from amazon):
ASIN(unique id) | Price
1 | 201
2 | 194
3 | 195
.
.
n | 33
n+1 | 33
n+2 | 33
.
n+120 | 33
n+121 | 34
n+122 | 35
wherein the products from n to n+120 are equal. This will create an infinite loop to my getProducts function. How can I avoid this? Knowing that only 10 items are returned on each request and only 10 pages.

Answer 1

How can I avoid this?
I don't think you can with just using price. You have to divide your search into multiple sub-searches by using additional keywords. For example, if you're searching for "laptop", instead do searches on "laptop asus", "laptop dell", etc.
You can also filter on Browse node IDs, so if your results come from multiple browse nodes, you can do two or more searches.

Answer 2

Add the ItemPage parameter and increment it in a loop. You should be able to get up to 100 unique ASINs (10 pages of 10 products per page).
$page = 1;
while($page <= 10) {
$item_params = [
"Service" => "AWSECommerceService",
"Operation" => "ItemSearch",
"AWSAccessKeyId" => env('AWS_ACCESS_KEY_ID'),
"AssociateTag" => env('AWS_ASSOCIATE_TAG_ID'),
"SearchIndex" => "HomeGarden",
"ResponseGroup" => "ItemAttributes,SalesRank,Offers",
"Sort" => "-price",
"BrowseNode" => $item_params['BrowseNode'],
"MaximumPrice" => $max_price,
"MinimumPrice" => "0",
"ItemPage" => $page
];
// execute query and save data
//increment page number
$page++;
}