利用Yahoo! Search API开发自已的搜索引擎-php版
2018-09-07 15:03
美国东部时间3月1日，雅虎公司联合创始人之一的杨致远将宣布公司的搜索网络将进入Web服务。雅虎公司在网站建立了Yahoo Search Developer Network，公司计划在此纽约举行的搜索引擎战略大会(Search Engine Strategies Conference)上推出这一计划。该网络将允许开发者在雅虎搜索之上建立新的应用程序，其中包括图像、视频、新闻以及地区搜索等内容。想要使用这项服务的会员必须先去申请一个自已的ID号，注：每个ID号每天只能搜索5000次。
下面我们看一下，如何用PHP脚本调用Yahoo! Search API实现搜索的效果，全部脚本如下：
<?php
// Yahoo Web Services PHP Example Code
// Rasmus Lerdorf
//
$appid = YahooDemo;
// 在这输入你申请的ID号
$service = array(image=>
local=>
news=>
video=>
web=>
?>
<html>
<head><title>PHP Yahoo Web Service Example Code</title></head>
<body>
<form action=YahooSearchExample.php method=GET>
Search Term: <input type=text name=query /><br />
Zip Code: <input type=text name=zip /> (for local search)<br />
<input type=submit value= Go! />
<select name=type>
<?php foreach($service as $name => $val) {
if(!empty($_REQUEST[type]) && $name == $_REQUEST[type])
echo <option SELECTED>$name</option>\n;
else echo <option>$name</option>\n;
} ?>
</select>
</form>
<?php
function done() {?>
</body></html>
<?php
exit;
}
if(empty($_REQUEST[query]) !in_array($_REQUEST[type],array_keys($service))) done();
// Ok, here we go, we have the query and the type of search is valid
// First build the query
$q = ?query=.rawurlencode($_REQUEST[query]);
if(!empty($_REQUEST[zip])) $q.=&zip=.$_REQUEST[zip];
if(!empty($_REQUEST[start])) $q.=&start=.$_REQUEST[start];
$q .= &appid=$appid;
// Then send it to the appropriate service
$xml = file_get_contents($service[$_REQUEST[type]].$q);
// Parse the XML and check it for errors
if (!$dom = domxml_open_mem($xml,DOMXML_LOAD_PARSING,$error)) {
echo XML parse error\n;
foreach ($error as $errorline) {
/* For production use this should obviously be logged to a file instead */
echo $errorline[errormessage].<br />\n;
echo Node : . $errorline[nodename] . <br />\n;
echo Line : . $errorline[line] . <br />\n;
echo Column : . $errorline[col] . <br />\n;
}
done();
}
// Now traverse the DOM with this function
// It is basically a generic parser that turns limited XML into a PHP array
// with only a couple of hardcoded tags which are common across all the
// result xml from the web services
function xml_to_result($dom) {
$root = $dom->document_element();
$res[totalResultsAvailable] = $root->get_attribute(totalResultsAvailable);
$res[totalResultsReturned] = $root->get_attribute(totalResultsReturned);
$res[firstResultPosition] = $root->get_attribute(firstResultPosition);
$node = $root->first_child();
$i = 0;
while($node) {
switch($node->tagname) {
case Result:
$subnode = $node->first_child();
while($subnode) {
$subnodes = $subnode->child_nodes();
if(!empty($subnodes)) foreach($subnodes as $k=>$n) {
if(empty($n->tagname)) $res[$i][$subnode->tagname] = trim($n->get_content());
else $res[$i][$subnode->tagname][$n->tagname]=trim($n->get_content());
}
$subnode = $subnode->next_sibling();
}
break;
default:
$res[$node->tagname] = trim($node->get_content());
$i--;
break;
}
$i++;
$node = $node->next_sibling();
}
return $res;
}
$res = xml_to_result($dom);
// Ok, now that we have the results in an easy to use format,
// display them. Its quite ugly because I am using a single
// display loop to display every type and I dont really understand HTML
$first = $res[firstResultPosition];
$last = $first + $res[totalResultsReturned]-1;
echo <p>Matched ${res[totalResultsAvailable]}, showing $first to $last</p>\n;
if(!empty($res[ResultSetMapUrl])) {
echo <p>Result Set Map: <a href=\${res[ResultSetMapUrl]}\>${res[ResultSetMapUrl]}</a></p>\n;
}
for($i=0; $i<$res[totalResultsReturned]; $i++) {
foreach($res[$i] as $key=>$value) {
switch($key) {
case Thumbnail:
echo <img src=\${value[Url]}\ height=\${value[Height]}\ width=\${value[Width]}\ />\n;
break;
case Cache:
echo Cache: <a href=\${value[Url]}\>${value[Url]}</a> [${value[Size]}]<br />\n;
break;
case PublishDate:
echo <b>$key:</b> .strftime(%X %x,$value);
break;
default:
if(stristr($key,url)) echo <a href=\$value\>$value</a><br />\n;
else echo <b>$key:</b> $value<br />;
break;
}
}
echo <hr />\n;
}
// Create Previous/Next Page links
if($start > 1)
echo <a href=/YahooSearchExample.php.
?query=.rawurlencode($_REQUEST[query]).
&zip=.rawurlencode($_REQUEST[zip]).
&type=.rawurlencode($_REQUEST[type]).
&start=.($start-10).><-Previous Page</a> ;
if($last < $res[totalResultsAvailable])
echo <a href=/YahooSearchExample.php.
?query=.rawurlencode($_REQUEST[query]).
&zip=.rawurlencode($_REQUEST[zip]).
&type=.rawurlencode($_REQUEST[type]).
&start=.($last+1).>Next Page-></a>;
done();
?>
有兴趣的朋友还可以看一下由[动态网站制作指南]所制作的ASP版本：
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文章标题：利用Yahoo! Search API开发自已的搜索引擎-php版
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