使用ASIN获取亚马逊产品的价格和评级

Question

我正致力于使用php自定义脚本获取亚马逊产品（图书）的价格和评论。

我已经尝试了一些api来使它工作，但我无法使它工作。

到目前为止我所做的是

<?php

// Region code and Product ASIN
$response = getAmazonPrice("com", "B00KQPGRRE");

function getAmazonPrice($region, $asin) {

    $xml = aws_signed_request($region, array(
        "Operation" => "ItemLookup",
        "ItemId" => $asin,
        "IncludeReviewsSummary" => False,
        "ResponseGroup" => "Medium,OfferSummary",
    ));

    $item = $xml->Items->Item;
    $title = htmlentities((string) $item->ItemAttributes->Title);
    $url = htmlentities((string) $item->DetailPageURL);
    $image = htmlentities((string) $item->MediumImage->URL);
    $price = htmlentities((string) $item->OfferSummary->LowestNewPrice->Amount);
    $code = htmlentities((string) $item->OfferSummary->LowestNewPrice->CurrencyCode);
    $qty = htmlentities((string) $item->OfferSummary->TotalNew);

    if ($qty !== "0") {
        $response = array(
            "code" => $code,
            "price" => number_format((float) ($price / 100), 2, '.', ''),
            "image" => $image,
            "url" => $url,
            "title" => $title
        );
    }

    return $response;
}

function getPage($url) {

    $curl = curl_init($url);
    curl_setopt($curl, CURLOPT_FAILONERROR, true);
    curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, false);
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
    $html = curl_exec($curl);
    curl_close($curl);
    return $html;
}

function aws_signed_request($region, $params) {

    $public_key = "PUBLICKEY";
    $private_key = "PrivateKEY";

    $method = "GET";
    $host = "ecs.amazonaws." . $region;
    $host = "webservices.amazon." . $region;
    $uri = "/onca/xml";

    $params["Service"] = "AWSECommerceService";
    $params["AssociateTag"] = "AFID"; // Put your Affiliate Code here
    $params["AWSAccessKeyId"] = $public_key;
    $params["Timestamp"] = gmdate("Y-m-d\TH:i:s\Z");
    $params["Version"] = "2011-08-01";

    ksort($params);

    $canonicalized_query = array();
    foreach ($params as $param => $value) {
        $param = str_replace("%7E", "~", rawurlencode($param));
        $value = str_replace("%7E", "~", rawurlencode($value));
        $canonicalized_query[] = $param . "=" . $value;
    }

    $canonicalized_query = implode("&", $canonicalized_query);

    $string_to_sign = $method . "\n" . $host . "\n" . $uri . "\n" . $canonicalized_query;
    $signature = base64_encode(hash_hmac("sha256", $string_to_sign, $private_key, True));
    $signature = str_replace("%7E", "~", rawurlencode($signature));

    $request = "http://" . $host . $uri . "?" . $canonicalized_query . "&Signature=" . $signature;
    $response = getPage($request);

    var_dump($response);



    $pxml = @simplexml_load_string($response);
    if ($pxml === False) {
        return False;// no xml
    } else {
        return $pxml;
    }

请在我的代码或我可以使用的任何其他代码建议中建议我缺少的内容。

提前致谢。