code:php代码片断 读magpie_rss的源码

tags:file,php,md5,magpierss
操作文件
//打开，写，关闭 文件，序列化对象
$cache_file = $file_name;
$fp = @fopen( $cache_file, 'w' );//打开文件 ，@不返回错误
if ( ! $fp ) {
$this->error(
"Cache unable to open file for writing: $cache_file"
);
return 0;
}
$data = $this->serialize( $rss );//序列化对象
fwrite( $fp, $data );//写文件
fclose( $fp );//关闭文件

//检测文件是否存在
file_exists( $filename ) ;

//获取文件修改时间
$mtime = filemtime( $filename );
//计算时间间隔
$age = time() - $mtime;

//读取文件，反序列化
$fp = @fopen($cache_file, 'r');
if ( ! $fp ) {
$this->error(
"Failed to open cache file for reading: $cache_file"
);
return 0;
}

if ($filesize = filesize($cache_file) ) {
$data = fread( $fp, filesize($cache_file) );
$rss = $this->unserialize( $data );

return $rss;
}


//md5生成文件名
function file_name ($url) {
$filename = md5( $url );
return join( DIRECTORY_SEPARATOR, array( $this->BASE_CACHE, $filename ) );
}

//设置http头,以提供etag和last_modified的支持
if ( $rss and $rss->etag and $rss->last_modified ) {
$request_headers['If-None-Match'] = $rss->etag;
$request_headers['If-Last-Modified'] = $rss->last_modified;
}

//使用 snoopy 请求远程资源

$resp = _fetch_remote_file( $url, $request_headers );

//封装 Snoopy调用的创建方式
function _fetch_remote_file ($url, $headers = "" ) {
// Snoopy is an HTTP client in PHP
$client = new Snoopy();
$client->agent = MAGPIE_USER_AGENT;
$client->read_timeout = MAGPIE_FETCH_TIME_OUT;
$client->use_gzip = MAGPIE_USE_GZIP;
if (is_array($headers) ) {
$client->rawheaders = $headers;
}
@$client->fetch($url);
return $client;
}
//判断Snoopy的返回值，并进行读取操作
if (isset($resp) and $resp) {
if ($resp->status == '304' ) {
// we have the most current copy
if ( MAGPIE_DEBUG > 1) {
debug("Got 304 for $url");
}
// reset cache on 304 (at minutillo insistent prodding)
$cache->set($cache_key, $rss);
return $rss;
}
elseif ( is_success( $resp->status ) ) {
$rss = _response_to_rss( $resp );
if ( $rss ) {
if (MAGPIE_DEBUG > 1) {
debug("Fetch successful");
}
// add object to cache
$cache->set( $cache_key, $rss );
return $rss;
}
}
else {
$errormsg = "Failed to fetch $url ";
if ( $resp->status == '-100' ) {
$errormsg .= "(Request timed out after " . MAGPIE_FETCH_TIME_OUT . " seconds)";
}
elseif ( $resp->error ) {
# compensate for Snoopy's annoying habbit to tacking
# on '\n'
$http_error = substr($resp->error, 0, -2);
$errormsg .= "(HTTP Error: $http_error)";
}
else {
$errormsg .= "(HTTP Response: " . $resp->response_code .')';
}
}
}
else {
$errormsg = "Unable to retrieve RSS file for unknown reasons.";
}

//判断http返回值
/*=======================================================================* Function: is_info
Purpose: return true if Informational status code
\*=======================================================================*/
function is_info ($sc) {
return $sc >= 100 && $sc < 200;
}

/*=======================================================================* Function: is_success
Purpose: return true if Successful status code
\*=======================================================================*/
function is_success ($sc) {
return $sc >= 200 && $sc < 300;
}

/*=======================================================================* Function: is_redirect
Purpose: return true if Redirection status code
\*=======================================================================*/
function is_redirect ($sc) {
return $sc >= 300 && $sc < 400;
}

/*=======================================================================* Function: is_error
Purpose: return true if Error status code
\*=======================================================================*/
function is_error ($sc) {
return $sc >= 400 && $sc < 600;
}

/*=======================================================================* Function: is_client_error
Purpose: return true if Error status code, and its a client error
\*=======================================================================*/
function is_client_error ($sc) {
return $sc >= 400 && $sc < 500;
}

/*=======================================================================* Function: is_client_error
Purpose: return true if Error status code, and its a server error
\*=======================================================================*/
function is_server_error ($sc) {
return $sc >= 500 && $sc < 600;
}

--
[:p] --飞扬.轻狂 [fallseir.lee]
http://fallseir.livejournal.com
http://feed.feedsky.com/fallseir