File Source for Weather

<?php
/**
* PolarLava::Weather - A class to retrieve XML weather from the NOAA NWS.
*
* This class requires PHP >= 5.0.0
*
* @package PolarLavaWeather
* @version 1.0.1
* @copyright Copyright 2006-2007 Kevin L. Papendick
* @author Kevin L. Papendick <kevinp@polarlava.com>
* @license http://opensource.org/licenses/gpl-license.php GNU Public License
* @filesource
*/
/**
* PolarLava::Weather - A class to retrieve XML weather from the NOAA NWS.
*
* This class requires PHP >= 5.0.0
*
* @package PolarLavaWeather
*/
class Weather {
/**
* @var string Local XML data cache directory
* @access protected
*/
protected $_cache_dir;
/**
* @var int Local XML data cache valid time in minutes
* @access protected
*/
protected $_cache_time;
/**
* @var int Local XML station data cache valid time in minutes
* @access protected
*/
protected $_cache_time_sid;
/**
* @var boolean Error flag
* @access protected
*/
protected $_error;
/**
* @var string Error message for user
* @access protected
*/
protected $_error_msg_user;
/**
* @var string Error message for debugging
* @access protected
*/
protected $_error_msg_debug;
/**
* @var string Local conditions image directory
* @access protected
*/
protected $_image_dir;
/**
* @var string The weather observation station
* @access protected
*/
protected $_obs_station;
/**
* @var array weather station data array
* @access private
*/
private $_station_array;
/**
* @var string The base weather service URL
* @access protected
*/
protected $_url;
/**
* @var array weather data array
* @access private
*/
private $_weather_array;
/**
* @var string XML weather data
* @access private
* @link http://www.weather.gov/data/current_obs/
*/
private $_xml;
/**
* Weather object constructor
*
* Accepts an array of configuration parameters as key/value pairs:
* <ul>
* <li>'url' => 'Weather service XML url' default NOAA/NWS</li>
* <li>'obs_station' => 'observation station code' default 'KIAG'</li>
* <li>'image_dir' => 'local image directory' default NULL</li>
* <li>'cache_dir' => 'local cache directory' default NULL</li>
* <li>'cache_time' => 'local cache time in minutes' default 60 minutes</li>
* <li>'cache_time_sid' => 'local cache time in minutes' for station data. Default 10080 (7 days)</li>
* <li>'fetch_weather' => boolean flag, TRUE fetches weather data (default)</li>
* <li>'fetch_stations' => boolean flag, TRUE fetches available weather stations data</li>
* <li>'cache_stations' => boolean flag, TRUE serializes station data to cache</li>
* </ul>
*
* @param array $params
*/
public function __construct($params = array()) {
$this->setError(FALSE);
//Set Parameters
$url = (array_key_exists('url', $params)) ? $params['url'] : 'http://www.weather.gov/xml/current_obs/';
$loc = (array_key_exists('obs_station', $params)) ? $params['obs_station'] : 'KIAG';
$image_dir = (array_key_exists('image_dir', $params)) ? $params['image_dir'] : NULL;
$cache_dir = (array_key_exists('cache_dir', $params)) ? $params['cache_dir'] : NULL;
$cache_time = (array_key_exists('cache_time', $params)) ? (int) $params['cache_time'] : 60;
$cache_time_sid = (array_key_exists('cache_time_sid', $params)) ? (int) $params['cache_time_sid'] : 10080; //1 week
$fetch_weather = (array_key_exists('fetch_weather', $params)) ? $params['fetch_weather'] : TRUE;
$fetch_stations = (array_key_exists('fetch_stations', $params)) ? $params['fetch_stations'] : FALSE;
$cache_stations = (array_key_exists('cache_stations', $params)) ? $params['cache_stations'] : FALSE;
$this->setUrl($url);
$this->setObsStation($loc);
$this->setImageDir($image_dir);
$this->setCacheDir($cache_dir);
$this->setCachetime($cache_time);
$this->setCachetimeSid($cache_time_sid);
if ($fetch_weather) {
$this->_getWeatherXml();
$this->_setWeatherArray();
$this->_setLocalImage();
}
if ($fetch_stations) {
$this->_getWeatherStationXml();
$this->_setStationArray();
if ($cache_stations && $cache_dir) {
$this->_setStationCache();
}
}
}
/***********************/
/***** Set Methods *****/
/***********************/
/**
* Set the local XML data cache directory.
*
* @param string
* @return NULL
*/
public function setCacheDir($a) {
$this->_cache_dir = $a;
}
/**
* Set the local XML data cache valid time in minutes.
*
* @param int
* @return NULL
*/
public function setCacheTime($a) {
$this->_cache_time = $a;
}
/**
* Set the local XML station data cache valid time in minutes.
*
* @param int
* @return NULL
*/
public function setCacheTimeSid($a) {
$this->_cache_time_sid = $a;
}
/**
* Set the error flag and message.
*
* @access protected
* @param boolean $err
* @param string $usr_msg The user error message
* @param string $dbg_msg The debug error message
* @return NULL
*/
protected function setError($err, $usr_msg = NULL, $dbg_msg = NULL) {
$this->_error = $err;
$this->_error_msg_user = $usr_msg;
$this->_error_msg_debug = $dbg_msg;
}
/**
* Set the local conditions image directory.
*
* @param string
* @return NULL
*/
public function setImageDir($a) {
$this->_image_dir = $a;
}
/**
* Checks and retrieves the local conditions image.
*
* @access protected
* @return NULL
*/
protected function _setLocalImage() {
$dir = $this->getImageDir();
$icon = $this->getWeatherElement('icon_url_name');
if (!is_null($dir)) {
$image = $dir . $icon;
if (!file_exists($image)) {
$url = $this->getWeatherElement('icon_url_base') . $icon;
$curl = curl_init();
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
$curl_data = curl_exec($curl);
curl_close($curl);
file_put_contents($image, $curl_data, LOCK_EX);
@chmod($image, 0666);
}
}
}
/**
* Set the weather observation station.
*
* @param string
* @return NULL
* @link http://www.weather.gov/data/current_obs/
*/
public function setObsStation($a) {
$this->_obs_station = $a;
}
/**
* Set the weather data base URL.
*
* @param string
* @return NULL
*/
public function setUrl($a) {
$this->_url = $a;
}
/**
* Convert XML weather data to array
*
* @access protected
* @return boolean success status
*/
protected function _setWeatherArray() {
$stat = TRUE;
$this->_weather_array = array();
$values = array();
$xml_parser = xml_parser_create();
xml_parse_into_struct($xml_parser, $this->getXml(), $values);
xml_parser_free($xml_parser);
foreach (new ArrayObject($values) as $xml_elem) {
foreach (new ArrayObject($xml_elem) as $sub_elem) {
if($xml_elem['type'] !== 'cdata') {
$this->_weather_array[strtolower($xml_elem['tag'])] = $xml_elem['value'];
break;
}
}
}
if (count($this->_weather_array) > 0) {
//--- Clean up in isle 3!
$stat = TRUE;
if (strpos($this->_weather_array['icon_url_base'], 'www') === FALSE) {
//Correct 301 errors for local image download
$this->_weather_array['icon_url_base'] = str_replace('weather.gov', 'www.weather.gov', $this->_weather_array['icon_url_base']);
}
$this->_weather_array['credit_image'] = $this->_weather_array['url'];
unset($this->_weather_array['url']);
unset($this->_weather_array['image']);
unset($this->_weather_array['current_observation']);
ksort($this->_weather_array);
//--- Integrity Check
$size = count($this->_weather_array);
if ($size !== 43) {
$this->setError(TRUE, 'Incomplete weather data retrieved.', "Only $size of 43 weather elements appear in the Weather::_weather_array.");
$stat = FALSE;
}
}
return $stat;
}
/**
* Convert XML weather station data to array
*
* @access protected
* @return boolean success status
*/
protected function _setStationArray() {
$stat = FALSE;
$this->_station_array = array();
$cache_dir = $this->getCacheDir();
$cache_file = $cache_dir . 'stations.dat';
$now = time();
if (!is_null($cache_dir) && file_exists($cache_file)) {
if (filemtime($cache_file) + ($this->getCacheTimeSid() * 60) >= $now) {
$this->_station_array = unserialize(file_get_contents($cache_file));
$stat = TRUE;
}
}
if (!$stat) {
$values = array();
$xml_parser = xml_parser_create();
xml_parse_into_struct($xml_parser, $this->getXml(), $values);
xml_parser_free($xml_parser);
$sid = '';
$state = '';
set_time_limit(600);
foreach (new ArrayObject($values) as $xml_elem) {
foreach (new ArrayObject($xml_elem) as $sub_elem) {
if($xml_elem['tag'] == 'STATION_ID') {
$sid = $xml_elem['value'];
break;
} elseif($xml_elem['tag'] == 'STATE') {
$state = $xml_elem['value'];
break;
} elseif($xml_elem['tag'] == 'STATION_NAME') {
$this->_station_array[$state][$sid] = $xml_elem['value'];
$sid = '';
$state = '';
break;
}
}
}
$stat = FALSE;
}
return $stat;
}
/**
* Serializes weather station data array and saves it to cache_dir
*
* @access protected
* @return boolean success status
*/
protected function _setStationCache() {
$stat = FALSE;
if (!is_null($this->getCacheDir())) {
$cache_file = $this->getCacheDir() . 'stations.dat';
file_put_contents($cache_file, serialize($this->getStationArray()), LOCK_EX);
@chmod($cache_file, 0666);
}
return (boolean) $stat;
}
/**
* Set the weather xml data.
*
* @access protected
* @param string
* @return NULL
*/
protected function setXml($a) {
$this->_xml = $a;
}
/***********************/
/***** Get Methods *****/
/***********************/
/**
* Get the local XML data cache directory.
*
* @return string $this->_cache_dir
*/
public function getCacheDir() {
return $this->_cache_dir;
}
/**
* Get the local cache valid time in minutes.
*
* @return int $this->_cache_time
*/
public function getCacheTime() {
return $this->_cache_time;
}
/**
* Get the local station cache valid time in minutes.
*
* @return int $this->_cache_time_sid
*/
public function getCacheTimeSid() {
return $this->_cache_time_sid;
}
/**
* Get the error status and messages.
*
* @return array $this->_error, $this->_error_msg_user, $this->_error_msg_debug
*/
public function getError() {
return array('error' => $this->_error,
'user_msg' => $this->_error_msg_user,
'debug_msg' => $this->_error_msg_debug);
}
/**
* Get the local conditions image directory.
*
* @return string $this->_image_dir
*/
public function getImageDir() {
return $this->_image_dir;
}
/**
* Get the weather observation station.
*
* @return string $this->_obs_station
*/
public function getObsStation() {
return $this->_obs_station;
}
/**
* Get the weather service URL.
*
* @return string $this->_url
*/
public function getUrl() {
return $this->_url;
}
/**
* Get the weather data array.
*
* @return string $this->_weather_array
*/
public function getWeatherArray() {
return $this->_weather_array;
}
/**
* Get the weather station data array.
*
* @return string $this->_station_array
*/
public function getStationArray() {
return $this->_station_array;
}
/**
* Get the weather stations from the station data array.
*
* @param string $state The location's stations.
* @return array $this->_station_array[$state]
*/
public function getStations($state) {
return $this->_station_array[$state];
}
/**
* Get a single element from the weather data array.
*
* @param string $a
* @return string $this->_weather_array[$a]
*/
public function getWeatherElement($a) {
if (array_key_exists($a, $this->_weather_array)) {
return $this->_weather_array[$a];
} else {
return NULL;
}
}
/**
* Get an array of all available data points from the weather data array.
*
* @return array Array keys from $this->_weather_array.
*/
public function getWeatherElements() {
if (isset($this->_weather_array)) {
return array_keys($this->_weather_array);
} else {
return NULL;
}
}
/**
* Retrieve XML weather data
*
* @access protected
* @param string $station_id Optional station ID. Default is getObsStation().
* @param int $cache_time Optional cache_time override
* @return boolean success status
*/
protected function _getWeatherXml($station_id = NULL, $cache_time = -1) {
$station_id = (is_null($station_id)) ? $this->getObsStation() : $station_id;
$cache_dir = $this->getCacheDir();
$cache_file = $cache_dir . $station_id . '.xml';
$cache_time = ($cache_time === -1) ? $this->getCacheTime() : $cache_time;
$now = time();
$stat = FALSE;
if (!is_null($cache_dir) && file_exists($cache_file)) {
if (filemtime($cache_file) + ($cache_time * 60) >= $now) {
$this->setXml(file_get_contents($cache_file));
$stat = TRUE;
}
}
if (!$stat) {
$curl = curl_init();
curl_setopt($curl, CURLOPT_URL, $this->getUrl() . $station_id . '.xml');
curl_setopt($curl, CURLOPT_HEADER, FALSE);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, TRUE);
$xml = curl_exec($curl);
if (curl_errno($curl)) {
$u = 'An error has occurred retrieving the weather XML data.';
$d = 'cURL Error in Weather::_getXML: ' . curl_error($curl);
$this->setError(TRUE, $u, $d);
$stat = FALSE;
} else {
if (!is_null($cache_dir)) {
file_put_contents($cache_file, $xml, LOCK_EX);
@chmod($cache_file, 0666);
}
$this->setXml($xml);
$stat = TRUE;
}
curl_close($curl);
}
return $stat;
}
/**
* Retrieve XML weather station data
*
* @access protected
* @return boolean success status
*/
protected function _getWeatherStationXml() {
return $this->_getWeatherXml('index', $this->getCacheTimeSid());
}
/**
* Get the weather xml data.
*
* @return string $this->_xml
*/
public function getXml() {
return $this->_xml;
}
/*************************/
/***** Other Methods *****/
/*************************/
/**
* Return an array dump of the (parsed XML) weather data
*
* @return array
*/
public function __toArray() {
return print_r($this->getWeatherArray(), TRUE);
}
/**
* Return a dump of the XML data
*
* @return array
*/
public function __toString() {
return print_r($this->getXml(), TRUE);
}
}
?>

Documentation generated on Sun, 18 Mar 2007 09:38:32 -0400 by phpDocumentor 1.3.1

Source for file Weather_class.php