我正在尝试从Amazon Product API获取输出using code from this website。
它有3个部分：
正如亚马逊一样，我需要在代码中插入3个值：
在API类中，可以清楚地插入这些值的位置：
require_once 'aws_signed_request.php';
class AmazonProductAPI
{
private $public_key = "YOUR AMAZON ACCESS KEY ID";
private $private_key = "YOUR AMAZON SECRET KEY";
/* 'Associate Tag' now required, effective from 25th Oct. 2011 */
private $associate_tag = "YOUR AMAZON ASSOCIATE TAG";
const MUSIC = "Music";
const DVD = "DVD";
const GAMES = "VideoGames";
private function verifyXmlResponse($response)
{
if ($response === False)
{
throw new Exception("Could not connect to Amazon");
}
else
{
if (isset($response->Items->Item->ItemAttributes->Title))
{
return ($response);
}
else
{
throw new Exception("Invalid xml response.");
}
}
}
private function queryAmazon($parameters)
{
return aws_signed_request("com",
$parameters,
$this->public_key,
$this->private_key,
$this->associate_tag);
}
public function searchProducts($search,$category,$searchType="UPC")
{
$allowedTypes = array("UPC", "TITLE", "ARTIST", "KEYWORD");
$allowedCategories = array("Music", "DVD", "VideoGames");
switch($searchType)
{
case "UPC" :
$parameters = array("Operation" => "ItemLookup",
"ItemId" => $search,
"SearchIndex" => $category,
"IdType" => "UPC",
"ResponseGroup" => "Medium");
break;
case "TITLE" :
$parameters = array("Operation" => "ItemSearch",
"Title" => $search,
"SearchIndex" => $category,
"ResponseGroup" => "Medium");
break;
}
$xml_response = $this->queryAmazon($parameters);
return $this->verifyXmlResponse($xml_response);
}
public function getItemByUpc($upc_code, $product_type)
{
$parameters = array("Operation" => "ItemLookup",
"ItemId" => $upc_code,
"SearchIndex" => $product_type,
"IdType" => "UPC",
"ResponseGroup" => "Medium");
$xml_response = $this->queryAmazon($parameters);
return $this->verifyXmlResponse($xml_response);
}
public function getItemByAsin($asin_code)
{
$parameters = array("Operation" => "ItemLookup",
"ItemId" => $asin_code,
"ResponseGroup" => "Medium");
$xml_response = $this->queryAmazon($parameters);
return $this->verifyXmlResponse($xml_response);
}
public function getItemByKeyword($keyword, $product_type)
{
$parameters = array("Operation" => "ItemSearch",
"Keywords" => $keyword,
"SearchIndex" => $product_type);
$xml_response = $this->queryAmazon($parameters);
return $this->verifyXmlResponse($xml_response);
}
}
但是这个API类最初使用的是Sign Request。 在签名请求中，我不知道在哪里插入这3个值：
<?php
function aws_signed_request($region,
$params,
$public_key,
$private_key,
$associate_tag)
{
$method = "GET";
$host = "ecs.amazonaws.".$region;
$uri = "/onca/xml";
$params["Service"] = "AWSECommerceService";
$params["AWSAccessKeyId"] = $public_key;
$params["AssociateTag"] = $associate_tag;
$params["Timestamp"] = gmdate("Y-m-d\TH:i:s\Z");
$params["Version"] = "2009-03-31";
/* The params need to be sorted by the key, as Amazon does this at
their end and then generates the hash of the same. If the params
are not in order then the generated hash will be different from
Amazon thus failing the authentication process.
*/
ksort($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;
/* calculate the signature using HMAC, SHA256 and base64-encoding */
$signature = base64_encode(hash_hmac("sha256",
$string_to_sign, $private_key, True));
/* encode the signature for the request */
$signature = str_replace("%7E", "~", rawurlencode($signature));
/* create request */
$request = "http://".$host.$uri."?".$canonicalized_query."&Signature=".$signature;
/* I prefer using CURL */
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,$request);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_TIMEOUT, 15);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
$xml_response = curl_exec($ch);
if ($xml_response === False)
{
return False;
}
else
{
/* parse XML and return a SimpleXML object, if you would
rather like raw xml then just return the $xml_response.
*/
$parsed_xml = @simplexml_load_string($xml_response);
return ($parsed_xml === False) ? False : $parsed_xml;
}
}
?>
答案 0 :(得分：1)
您无需在#import "UITagLabel.h"
#define padding UIEdgeInsetsMake(5, 10, 5, 10)
@implementation UITagLabel
- (void)drawTextInRect:(CGRect)rect {
[super drawTextInRect:UIEdgeInsetsInsetRect(rect, padding)];
}
- (CGSize) intrinsicContentSize {
CGSize superContentSize = [super intrinsicContentSize];
CGFloat width = superContentSize.width + padding.left + padding.right;
CGFloat height = superContentSize.height + padding.top + padding.bottom;
return CGSizeMake(width, height);
}
- (CGSize) sizeThatFits:(CGSize)size {
CGSize superSizeThatFits = [super sizeThatFits:size];
CGFloat width = superSizeThatFits.width + padding.left + padding.right;
CGFloat height = superSizeThatFits.height + padding.top + padding.bottom;
return CGSizeMake(width, height);
}
@end
中提供这些凭据，凭据在调用函数aws_signed_request.php时会从AmazonProductAPI类传递给该函数：
aws_signed_request直到那一点才真正调用该函数，private function queryAmazon($parameters)
{
return aws_signed_request("com",
$parameters,
$this->public_key, // <--- here!
$this->private_key,
$this->associate_tag);
}
只是使函数可用。