ip_geoloc_api.inc in IP Geolocation Views & Maps 7
Same filename and directory in other branches
API functions of IP geolocation module
Reusable functions that may be called from other modules.
File
ip_geoloc_api.incView source
<?php
/**
* @file
* API functions of IP geolocation module
*
* Reusable functions that may be called from other modules.
*/
// Note: secure http was chosen, as plain http may cause warnings popping up in
// environments using certificates.
// IP_GEOLOC_GOOGLE_MAPS is only used for client-side geocoding to an address,
// if enabled on "Set my location" block options.
define('IP_GEOLOC_GOOGLE_MAPS', ip_geoloc_build_google_api_url());
// Server-side reverse geocoding of an entered address, if enabled.
define('IP_GEOLOC_GOOGLE_MAPS_SERVER', 'https://maps.googleapis.com/maps/api/geocode/json');
/**
* Store the supplied IP geolocation info on the database.
*
* This will overwrite any existing info for the IP address in question.
*
* @param array $location
* array with up to 13 location info fields; must at least
* contain a non-empty $location['ip_address'] and a non-empty
* $location['formatted_address'] for anything to happen
*
* @return int|bool
* 0, when no insert or update was necessary
* SAVED_NEW (=1), when a new location record was inserted into the db
* SAVED_UPDATED (=2), when an existing location record was updated
* FALSE, when a db insert or db update failed
*/
function ip_geoloc_store_location($location) {
// Give contributed modules a chance to add their 2 cents by implementing
// hook_get_ip_geolocation_alter()
drupal_alter('get_ip_geolocation', $location);
if (!variable_get('ip_geoloc_store_addresses', TRUE)) {
return;
}
if (empty($location['ip_address']) || empty($location['formatted_address'])) {
// ip_geoloc_debug('IPGV&M: location object must contain both IP address
// and formatted address -- not stored.');
return 0;
}
if ($location['ip_address'] != '127.0.0.1' && (!isset($location['latitude']) || !isset($location['latitude']))) {
watchdog('IPGV&M', 'latitude or longitude missing for IP address %ip (location still stored)', array(
'%ip' => $location['ip_address'],
), WATCHDOG_WARNING);
}
// See if this IP is already on the db.
$result = db_query('SELECT * FROM {ip_geoloc} WHERE ip_address = :ip', array(
':ip' => $location['ip_address'],
));
$existing_location = $result
->fetchAssoc();
if (!$existing_location) {
// New entry, insert.
$location['city'] = utf8_encode($location['city']);
$location['formatted_address'] = utf8_encode($location['formatted_address']);
ip_geoloc_debug(t('IP Geolocaton: adding new record to db: !location', array(
'!location' => ip_geoloc_pretty_print($location),
)));
$full_location =& $location;
}
else {
// When updating, drupal_write_record() does not erase fields not present
// in $location.
$empty_location['latitude'] = '';
$empty_location['longitude'] = '';
$empty_location['country'] = '';
$empty_location['country_code'] = '';
$empty_location['region'] = '';
$empty_location['region_code'] = '';
$empty_location['city'] = '';
$empty_location['locality'] = '';
$empty_location['route'] = '';
$empty_location['street_number'] = '';
$empty_location['postal_code'] = '';
$empty_location['administrative_area_level_1'] = '';
$empty_location['formatted_address'] = '';
$location['id'] = $existing_location['id'];
$full_location = array_merge($empty_location, $location);
ip_geoloc_debug(t('IPGV&M: updating db with above location'));
}
try {
$result = drupal_write_record('ip_geoloc', $full_location, $existing_location ? array(
'id',
) : array());
} catch (PDOException $e) {
// May happen when a fields contains illegal characters.
drupal_set_message(check_plain($e
->getMessage()), 'error');
$result = FALSE;
}
if ($result === FALSE) {
drupal_set_message(t('IPGV&M: could not save location to db: !location', array(
'!location' => ip_geoloc_pretty_print($full_location),
)), 'error');
}
return $result;
}
/**
* Outputs an HTML div placeholder into which will be injected a map.
*
* The map is centered on the supplied lat,long coordinates.
* Handy for use in Views.
*
* @param string|float $latitude
* e.g. "-37.87" or -37.87
* @param string|float $longitude
* e.g. "144.98" or 144.98
* @param string $div_id
* id of the div placeholder, can be anything as long as it's unique
* @param string $style
* CSS style applied to the div, e.g "height:250px; width:300px"
*/
function ip_geoloc_output_map($latitude, $longitude, $div_id = 'ip-geoloc-map', $style = '', $balloon_text = '') {
drupal_add_js(IP_GEOLOC_GOOGLE_MAPS, array(
'type' => 'external',
'group' => JS_LIBRARY,
));
drupal_add_js(drupal_get_path('module', 'ip_geoloc') . '/js/ip_geoloc_gmap.js');
$script_code = "displayGMap({$latitude}, {$longitude}, '{$div_id}', '{$balloon_text}');";
drupal_add_js($script_code, array(
'type' => 'inline',
'scope' => 'footer',
));
$map_placeholder = "<div id='{$div_id}'" . (empty($style) ? '' : " style='{$style}'") . '></div>';
return $map_placeholder;
}
/**
* Outputs an HTML div placeholder into which is injected a map.
*
* The map is centered on the visitor's current location and features a position
* marker, which when clicked reveals latitude and longitude, as well as the
* street address and the accuracy of the position shown.
*
* Note this function will result in the visitor being prompted to share their
* location.
*
* @param string $div_id
* id of the div placeholder, can be anything as long as it's unique
* @param string $map_options
* as a JSON string e.g '{"mapTypeId":"roadmap", "zoom":15}'
* @param string $map_style
* CSS style applied to the div, e.g "height:200px; width:300px"
* @param float $latitude
* if empty and HTML5 location retrieval will be initiated
* @param float $longitude
* if empty and HTML5 location retrieval will be initiated
* @param string $info_text
* optional string to display in the marker balloon, e.g. formatted address
*/
function ip_geoloc_output_map_current_location($div_id = 'ip-geoloc-map-current-location', $map_options = NULL, $map_style = NULL, $latitude = NULL, $longitude = NULL, $info_text = NULL) {
drupal_add_js(IP_GEOLOC_GOOGLE_MAPS, array(
'type' => 'external',
'group' => JS_LIBRARY,
));
drupal_add_js(drupal_get_path('module', 'ip_geoloc') . '/js/ip_geoloc_gmap_current_loc.js');
if (!isset($map_options)) {
$map_options = IP_GEOLOC_CURRENT_VISITOR_MAP_OPTIONS;
}
$settings = array(
'ip_geoloc_current_location_map_div' => $div_id,
'ip_geoloc_current_location_map_options' => drupal_json_decode($map_options),
'ip_geoloc_current_location_map_latlng' => array(
$latitude,
$longitude,
),
'ip_geoloc_current_location_map_info_text' => $info_text,
);
drupal_add_js($settings, 'setting');
if (!isset($map_style)) {
$map_style = IP_GEOLOC_MAP_DIV_DEFAULT_STYLE;
}
$map_placeholder = "<div id='{$div_id}'" . (empty($map_style) ? '' : " style='{$map_style}'") . '></div>';
return $map_placeholder;
}
/**
* Outputs an HTML div placeholder into which will be injected a map.
*
* The locations to be mapped are supplied as an array of lat,long coordinates.
*
* @param array $locations
* array of location objects each containing lat/long pair and optionally
* address, visit count and last visit to appear when the marker is clicked
* @param string $div_id
* id of the div placeholder, can be anything as long as it's unique
* @param string $map_options
* as a JSON string, .e.g '{"mapTypeId":"roadmap", "zoom":15}'
* @param string $map_style
* CSS style applied to the div, e.g "height:250px; width:300px"
*/
function ip_geoloc_output_map_multi_visitor($locations, $div_id = 'ip-geoloc-map-multi-locations', $map_options = NULL, $map_style = NULL) {
drupal_add_js(IP_GEOLOC_GOOGLE_MAPS, array(
'type' => 'external',
'group' => JS_LIBRARY,
));
drupal_add_js(drupal_get_path('module', 'ip_geoloc') . '/js/ip_geoloc_gmap_multi_visitor.js');
if (!isset($map_options)) {
$map_options = IP_GEOLOC_RECENT_VISITORS_MAP_OPTIONS;
}
$settings = array(
'ip_geoloc_locations' => $locations,
'ip_geoloc_multi_location_map_div' => $div_id,
'ip_geoloc_multi_location_map_options' => drupal_json_decode($map_options),
);
drupal_add_js($settings, 'setting');
if (!isset($map_style)) {
$map_style = IP_GEOLOC_MAP_DIV_DEFAULT_STYLE;
}
$map_placeholder = "<div id='{$div_id}'" . (empty($map_style) ? '' : " style='{$map_style}'") . '></div>';
return $map_placeholder;
}
/**
* Outputs an HTML div placeholder into which will be injected a Google map.
*
* The locations to be mapped are supplied as an array of location objects,
* each with lat,long coordinates and optional balloon text.
*
* Note this function will result in the visitor being prompted to share their
* location.
*
* @param array $locations
* array of location objects each containing lat/long pair
* and optional balloon text.
*
* @param string $div_id
* id of the div placeholder, can be anything as long as it's unique
*
* @param string $map_options
* as a JSON string, .e.g '{"mapTypeId":"roadmap", "zoom":15}'
*
* @param string $map_style
* CSS style applied to the div, e.g "height:250px; width:300px"
*
* @param string $marker_color
* default color used for all locations that haven't had their
* color overridden, defaults to Google default (i.e. red marker with dot).
*
* @param bool|string $visitor_marker
* FALSE (no marker), TRUE (standard red marker) or a 'RRGGBB' color code
*
* @param int $center_option
* 0: fixed cenrer, must be provided thorugh $map_options)
* 1: auto-center the map on the first location in the $locations array
* 2: auto-center the map on the visitor's current location
*
* @param array $center_latlng
* array of length 2 with lat/long coords used as a backup
* when $visitor_marker is set or $center_option == 2 and location could not
* be determined or $visitor_location_gps == FALSE
*
* @param bool $visitor_location_gps
* whether the HTML5-style location provider is to be
* used, if FALSE $center_latlng is used
*
* @return string
* map placeholder div
*/
function ip_geoloc_output_map_multi_location($locations, $div_id = 'ip-geoloc-map-multi-locations', $map_options = NULL, $map_style = NULL, $marker_color = NULL, $visitor_marker = TRUE, $center_option = 0, $center_latlng = array(
0,
0,
), $visitor_location_gps = TRUE) {
drupal_add_js(IP_GEOLOC_GOOGLE_MAPS, array(
'type' => 'external',
'group' => JS_LIBRARY,
));
drupal_add_js(drupal_get_path('module', 'ip_geoloc') . '/js/ip_geoloc_gmap_multi_loc.js');
if (!isset($map_options)) {
$map_options = IP_GEOLOC_RECENT_VISITORS_MAP_OPTIONS;
}
$marker_directory = file_create_url(ip_geoloc_marker_directory());
$marker_dimensions = explode('x', ip_geoloc_marker_dimensions());
$marker_width = (int) $marker_dimensions[0];
$marker_height = (int) $marker_dimensions[1];
switch (variable_get('ip_geoloc_marker_anchor_pos', 'bottom')) {
case 'top':
$marker_anchor = 0;
break;
case 'middle':
$marker_anchor = (int) (($marker_height + 1) / 2);
break;
default:
$marker_anchor = $marker_height;
}
ip_geoloc_debug(t('IPGV&M: passing the following to Google Maps:'));
ip_geoloc_debug(t('- map options %options:', array(
'%options' => $map_options,
)));
ip_geoloc_debug(t('- center option: @option', array(
'@option' => $center_option,
)));
ip_geoloc_debug(t('- visitor marker: %marker', array(
'%marker' => $visitor_marker,
)));
ip_geoloc_debug(t('- use GPS: @gps', array(
'@gps' => (bool) $visitor_location_gps,
)));
ip_geoloc_debug(t('- visitor location fallback: (@lat, @lng)', array(
'@lat' => empty($center_latlng[0]) ? '-' : $center_latlng[0],
'@lng' => empty($center_latlng[1]) ? '-' : $center_latlng[1],
)));
ip_geoloc_debug(t('- marker directory : %dir', array(
'%dir' => $marker_directory,
)));
ip_geoloc_debug(t('- marker dimensions : w@w x h@h px, anchor: @a px', array(
'@w' => $marker_width,
'@h' => $marker_height,
'@a' => $marker_anchor,
)));
ip_geoloc_debug(t('- @count locations found', array(
'@count' => count($locations),
)));
// Locations transferred to JS via the settings array aren't refreshed in
// AJAX contexts. That's why we are doing it this messy way. @todo: refactor.
print "\n<script>\nif (typeof(ip_geoloc_locations) === 'undefined') {\n ip_geoloc_locations = new Array();\n}\n";
print "ip_geoloc_locations['{$div_id}'] = [\n";
$illegal_chars = array(
"\n",
"\r",
);
foreach ($locations as $location) {
if (isset($location->type) && $location->type != 'point') {
continue;
}
// Balloon text must not have newlines, use <br/> instead.
$balloon_text = NULL;
if (!empty($location->balloon_text)) {
$balloon_text = str_replace($illegal_chars, ' ', $location->balloon_text);
$balloon_text = addslashes($balloon_text);
}
$output = '{' . '"type":"point"' . (empty($location->marker_color) ? '' : ',"marker_color":"' . $location->marker_color . '"') . (empty($balloon_text) ? '' : ',"balloon_text":"' . $balloon_text . '"') . (empty($location->open) ? '' : ',"open":1') . ',"latitude":' . $location->latitude . ',"longitude":' . $location->longitude . "},\n";
print $output;
$color = empty($location->marker_color) ? t('default') . " [{$marker_color}]" : $location->marker_color;
$coords = isset($location->latitude) ? $location->latitude . ', ' . $location->longitude : '';
$msg = '- ' . t('marker') . " {$color} ({$coords})<br/>{$balloon_text}<br/>";
ip_geoloc_debug($msg);
}
print "];\n</script>\n";
$settings = array(
'ip_geoloc_multi_location_map_div' => $div_id,
'ip_geoloc_multi_location_map_options' => drupal_json_decode($map_options),
'ip_geoloc_multi_location_center_option' => (int) $center_option,
'ip_geoloc_multi_location_center_latlng' => $center_latlng,
'ip_geoloc_multi_location_visitor_marker' => $visitor_marker,
'ip_geoloc_multi_location_visitor_location_gps' => $visitor_location_gps,
'ip_geoloc_multi_location_marker_directory' => $marker_directory,
'ip_geoloc_multi_location_marker_width' => (int) $marker_width,
'ip_geoloc_multi_location_marker_height' => (int) $marker_height,
'ip_geoloc_multi_location_marker_anchor' => (int) $marker_anchor,
'ip_geoloc_multi_location_marker_default_color' => $marker_color,
);
drupal_add_js(array(
$settings,
), 'setting');
if (!isset($map_style)) {
$map_style = IP_GEOLOC_MAP_DIV_DEFAULT_STYLE;
}
$map_placeholder = "<div id='{$div_id}'" . (empty($map_style) ? '' : " style='{$map_style}'") . '></div>';
return $map_placeholder;
}
/**
* Uses AJAX to return in $_POST info about the visitor's current location.
*
* Note: this function will result in the browser prompting the visitor to share
* their location, which they may or may not accept.
*
* This works via an asynchronous javascript call, so the result is not
* immediately available on return from this function, hence the $menu_callback.
* Upon page load the included javascript will, when ready, instigate an AJAX
* call to the $menu_callback, which should invoke a function to pull the
* lat/long and address values out of the $_POST variable.
* See ip_geoloc_current_location_ajax_recipient() for an example.
*
* Note: will result in a HTTP error 503 when the site is in maintenance mode,
* as in maintenance mode menu items are not available.
*/
function ip_geoloc_get_current_location($menu_callback = NULL, $reverse_geocode = NULL, $refresh_page = NULL) {
$throbber_text = variable_get('ip_geoloc_throbber_text2');
if (empty($throbber_text)) {
$throbber_text = IP_GEOLOC_THROBBER_DEFAULT_TEXT;
}
if ($throbber_text != '<none>') {
drupal_set_message(filter_xss_admin($throbber_text));
}
_ip_geoloc_set_session_value('last_position_check', time());
_ip_geoloc_set_session_value('position_pending_since', microtime(TRUE));
// Note that IP_GEOLOC_GOOGLE_MAPS includes Google API or Client key.
// See ip_geoloc_build_google_api_url().
drupal_add_js(IP_GEOLOC_GOOGLE_MAPS, array(
'type' => 'external',
'group' => JS_LIBRARY,
));
drupal_add_js(drupal_get_path('module', 'ip_geoloc') . '/js/ip_geoloc_current_location.js');
if (!isset($menu_callback)) {
global $base_url;
$menu_callback = "{$base_url}/" . (variable_get('clean_url', 0) ? 'js/ip_geoloc/current_location' : '?q=js/ip_geoloc/current_location');
}
if (!isset($reverse_geocode)) {
$reverse_geocode = variable_get('ip_geoloc_visitor_reverse_geocode', TRUE);
}
if (!isset($refresh_page)) {
$refresh_page = variable_get('ip_geoloc_page_refresh', TRUE) && !path_is_admin($_GET['q']);
}
$settings = array(
'ip_geoloc_menu_callback' => $menu_callback,
'ip_geoloc_refresh_page' => $refresh_page,
'ip_geoloc_reverse_geocode' => $reverse_geocode,
);
drupal_add_js($settings, 'setting');
}
/**
* Returns the location details associated with the supplied IP address.
*
* Performs a lookup in IPGV&M's own database to see if the supplied IP
* address has visited already and if so returns their location details (as an
* array). If the IP address is not yet in the IP geolocation database, then
* retrieve lat/long using either Smart IP or GeoIP API (if enabled) and
* reverse-geocode the lat/long (if the Google Maps service is enabled) into a
* location. If the third argument is TRUE, then store the new location.
*
* @param string $ip_address
* The IP address to locate
* @param bool $resample
* if set to TRUE, ignore any existing location data for this
* IP address and retrieve the latest
* @param bool $store
* if TRUE, store the new or resampled location on the db
* @param bool|null $reverse_geocode
* applies only when the supplied IP address is not
* yet on the database or $resample=TRUE; use TRUE, FALSE or NULL; TRUE will
* produce greater detail in the location returned; if NULL or omitted the
* value is taken from the tick box on the IP Geolocation configuration page.
* Reverse-geocoding is subject to a Google-imposed limit of 2500 calls per
* day from the same server IP address.
*
* @return array
* location as an array
*/
function ip_geoloc_get_location_by_ip($ip_address, $resample = FALSE, $store = FALSE, $reverse_geocode = NULL) {
$location = $resample ? NULL : db_query('SELECT * FROM {ip_geoloc} WHERE ip_address = :ip_address', array(
':ip_address' => $ip_address,
))
->fetchAssoc();
if (empty($location)) {
$location = array(
'ip_address' => $ip_address,
);
if (ip_geoloc_use_smart_ip_if_enabled($location) || ip_geoloc_use_geoip_api_if_enabled($location)) {
if (!isset($reverse_geocode)) {
$reverse_geocode = variable_get('ip_geoloc_google_to_reverse_geocode', FALSE);
}
if ($reverse_geocode && isset($location['latitude']) && isset($location['longitude'])) {
if ($google_address = ip_geoloc_reverse_geocode($location['latitude'], $location['longitude'])) {
// Should we clear out whatever Smart IP or GeoIP put in the $location
// to avoid fields contradicting eachother? Eg. Google normally
// returns 'locality', whereas Smart IP and GeoIP return 'city'.
// $location = array('ip_address' => $ip_address);
ip_geoloc_flatten_google_address($google_address, $location);
}
}
if ($store) {
// Calls drupal_alter().
ip_geoloc_store_location($location);
}
else {
drupal_alter('get_ip_geolocation', $location);
}
}
}
return $location;
}
/**
* Returns the formatted address reverse-geocoded from the supplied lat,long.
*
* See the CALLER BEWARE note at ip_geoloc_reverse_geocode().
*
* @param string|double $latitude
* e.g. "-37.87" or -37.87
* @param string|double $longitude
* e.g. "144.98" or 144.98
* @param string $lang
* optional language specification as a two-letter code, e.g. 'ja' (Japanese).
*
* @return string
* Formatted address component as received from Google or empty string.
*/
function ip_geoloc_get_address($latitude, $longitude, $lang = NULL) {
return $google_address = ip_geoloc_reverse_geocode($latitude, $longitude, $lang) ? $google_address['formatted_address'] : '';
}
/**
* Uses the Google webservice to retrieve address information based on lat/long.
*
* Effectively makes calls of this form:
* https://maps.googleapis.com/maps/api/geocode/json?latlng=-37.87,144.98
*
* CALLER BEWARE:
* This is a server-side, as opposed to client-side call. If you want to call
* this function repeatedly, remember that Google 1) requires an API key (free)
* and 2) imposes other restrictions, like quotas and billing.
*
* @param string|double $latitude
* e.g. "-37.87" or -37.87
* @param string|double $longitude
* e.g. "144.98" or 144.98
* @param string $lang
* optional language specification as a two-letter code, e.g. 'ja' (Japanese).
*
* @return array|bool
* Array of address components as received from Google or FALSE.
*/
function ip_geoloc_reverse_geocode($latitude, $longitude, $lang = NULL) {
if (empty($latitude) || empty($latitude)) {
drupal_set_message(t('IPGV&M: cannot reverse-geocode to address as no lat/long was specified.'), 'warning');
return FALSE;
}
$query_start = microtime(TRUE);
$url = IP_GEOLOC_GOOGLE_MAPS_SERVER . "?latlng={$latitude},{$longitude}";
if (!empty($lang)) {
$url .= "&language={$lang}";
}
$response = drupal_http_request($url);
if (!empty($response->error)) {
$msg_args = array(
'%url' => $url,
'@code' => $response->code,
'%error' => $response->error,
);
drupal_set_message(t('IPGV&M: the HTTP request %url returned the following error (code @code): %error.', $msg_args), 'error');
watchdog('IPGV&M', 'Error (code @code): %error. Request: %url', $msg_args, WATCHDOG_ERROR);
return FALSE;
}
$data = drupal_json_decode($response->data);
if ($data['status'] == 'OVER_QUERY_LIMIT') {
$msg_args = array(
'%url' => $url,
);
if (user_access('administer site configuration')) {
drupal_set_message(t('IPGV&M: Server is over its query limit. Request: %url', $msg_args), 'error');
}
watchdog('IPGV&M', 'Server is over its query limit. Request: %url', $msg_args, WATCHDOG_ERROR);
return FALSE;
}
if ($data['status'] == 'ZERO_RESULTS' || !isset($data['results'][0])) {
$msg_args = array(
'@protocol' => $response->protocol,
'%url' => $url,
);
drupal_set_message(t('IPGV&M: the @protocol request %url succeeded, but returned no results.', $msg_args), 'warning');
watchdog('IPGV&M', 'No results from @protocol request %url.', $msg_args, WATCHDOG_WARNING);
return FALSE;
}
if ($data['status'] != 'OK') {
$msg_args = array(
'%url' => $url,
'%error' => $data['status'],
);
drupal_set_message(t('IPGV&M: unknown error %error. Request: %url..', $msg_args), 'error');
watchdog('IPGV&M', 'Unknown error %error. Request: %url.', $msg_args, WATCHDOG_ERROR);
return FALSE;
}
$google_address = $data['results'][0];
if (empty($google_address['formatted_address'])) {
$msg_args = array(
'@lat' => $latitude,
'@long' => $longitude,
);
ip_geoloc_debug(t('IPGV&M: (@lat, @long) could not be reverse-geocoded to a street address.', $msg_args), 'warning');
watchdog('IPGV&M', '(@lat, @long) could not be reverse-geocoded to a street address..', $msg_args, WATCHDOG_WARNING);
}
else {
$sec = number_format(microtime(TRUE) - $query_start, 1);
$msg_args = array(
'@lat' => $latitude,
'@long' => $longitude,
'%sec' => $sec,
'%address' => $google_address['formatted_address'],
);
ip_geoloc_debug(t('IPGV&M: %address reverse-geocoded from (@lat, @long) in %sec s.', $msg_args));
watchdog('IPGV&M', '%address reverse-geocoded from (@lat, @long) in %sec s.', $msg_args, WATCHDOG_INFO);
}
return $google_address;
}
/**
* Return the visitor's location as currently stored in the session.
*
* @return array
* Lat/Lon array from SESSION
*/
function ip_geoloc_get_visitor_location() {
$location = _ip_geoloc_get_session_value('location');
drupal_alter('ip_geoloc_get_visitor_location', $location);
return $location;
}
/**
* Calculate the center of the supplied locations using one of two algorithms.
*
* The first algorithm returns the center of the rectangle whose horizontal
* sides pass through the top and bottom locations in the set, while its
* vertical sides pass through the left-most and right-most locations.
*
* The second algorithm returns the center of gravity of all supplied locations.
* The second algorithn is therefore sensitive to location clusters. This may
* be what you want, or it may be what you want to avoid.
*
* @param array $locations
* array of location objects each with latitude and longitude
*
* @param bool $center_of_gravity
* if TRUE use the center of gravity algorithm
*
* @return array
* containing latitude and longitude of the center
*/
function ip_geoloc_center_of_locations($locations, $center_of_gravity = FALSE) {
if (empty($locations)) {
return array(
NULL,
NULL,
);
}
if ($center_of_gravity) {
// Because longitude turns back on itself, cannot simply average coords.
$count = 0;
$x = $y = $z = 0.0;
foreach ($locations as $location) {
if (isset($location->lon)) {
$lng = $location->lon;
$lat = $location->lat;
}
elseif (isset($location->longitude)) {
$lng = $location->longitude;
$lat = $location->latitude;
}
else {
continue;
}
$lng = deg2rad($lng);
$lat = deg2rad($lat);
// Convert to Cartesian coords and total the 3 dimensions independently.
$x += cos($lat) * cos($lng);
$y += cos($lat) * sin($lng);
$z += sin($lat);
$count++;
}
$x /= $count;
$y /= $count;
$z /= $count;
$center_lat = atan2($z, sqrt($x * $x + $y * $y));
$center_lng = atan2($y, $x);
return array(
rad2deg($center_lat),
rad2deg($center_lng),
);
}
// Alternative method based on top & bottom lat and left & right lon.
$top = $bottom = $left = $right = NULL;
foreach ($locations as $location) {
if (isset($location->lon)) {
$lng = $location->lon;
$lat = $location->lat;
}
elseif (isset($location->longitude)) {
$lng = $location->longitude;
$lat = $location->latitude;
}
else {
continue;
}
if (!isset($top) || $lat > $top) {
$top = $lat;
}
if (!isset($bottom) || $lat < $bottom) {
$bottom = $lat;
}
if (!isset($left) || $lng < $left) {
$left = $lng;
}
if (!isset($right) || $lng > $right) {
$right = $lng;
}
}
if (!isset($top) || !isset($left)) {
return array(
NULL,
NULL,
);
}
$center_lat = 0.5 * ($top + $bottom);
$center_lng = 0.5 * ($left + $right);
if ($right - $left > 180) {
// If the angle between right and left is greater than 180, then averaging
// is still ok, provided we flip over to the opposite end of the world.
$center_lng = $center_lng > 0.0 ? $center_lng - 180.0 : $center_lng + 180.0;
}
return array(
$center_lat,
$center_lng,
);
}
/**
* Returns the distance (in meters) between two points on the earth's surface.
*
* The points are defined by their lat/long coordinates. If the second point is
* omitted, the current visitor's location is used, as taken from their session
* data.
*
* @param array $location
* must contain 'latitude' and 'longitude' keys and values
*
* @param array $ref_location
* if an array, must contain 'latitude' and 'longitude' keys and values,
* otherwise defaults to ip_geoloc_get_visitor_location()
*
* @return float
* distance in meters.
*/
function ip_geoloc_distance($location, $ref_location = 'current visitor') {
if (!is_array($ref_location)) {
$ref_location = ip_geoloc_get_visitor_location();
}
if (empty($ref_location)) {
return '?';
}
if (is_numeric($location['longitude']) && is_numeric($location['latitude']) && is_numeric($ref_location['longitude']) && is_numeric($ref_location['latitude'])) {
return ip_geoloc_earth_distance($location['longitude'], $location['latitude'], $ref_location['longitude'], $ref_location['latitude']);
}
return '?';
}
/**
* Returns the distance between two points on the earth's surface.
*
* The points are defined by their lat/long coordinates.
*
* Gratefully copied from the http://drupal.org/project/location module, thus
* ensuring compatibility of results.
*
* @param float $longitude1
* Must be in range -180..180.
*
* @param float $latitude1
* Must be in range -90..90.
*
* @param float $longitude2
* Must be in range -180..180.
*
* @param float $latitude2
* Must be in range -90..90
*
* @return float
* Distance between the two points in meters.
*
* @see http://en.wikipedia.org/wiki/Great-circle_distance
*/
function ip_geoloc_earth_distance($longitude1, $latitude1, $longitude2, $latitude2) {
$long1 = deg2rad($longitude1);
$lat1 = deg2rad($latitude1);
$long2 = deg2rad($longitude2);
$lat2 = deg2rad($latitude2);
// $long_factor = cos($long1) * cos($long2) + sin($long1) * sin($long2);
// This is identical to this $long_factor = cos($long1 - $long2).
$long_factor = cos($long1 - $long2);
$cosangle = cos($lat1) * cos($lat2) * $long_factor + sin($lat1) * sin($lat2);
$radius = ip_geoloc_earth_radius(0.5 * ($latitude1 + $latitude2));
$distance = acos($cosangle) * $radius;
/*
if ($distance < 1000) {
// see http://en.wikipedia.org/wiki/Haversine_formula
$sinlat = sin(0.5*($lat1 - $lat2));
$sinlong = sin(0.5*($long1 - $long2));
$sinangle = $sinlat*$sinlat + cos($long1)*cos($long2)*$sinlong*$sinlong;
$distance = 2.0 * asin(sqrt($sinangle)) * $radius;
}
*/
return $distance;
}
/**
* Get radius of the Earth at a given latitude.
*
* @param float $latitude
* The latitude for which to calculate Earth's radius
*
* @return float
* The radius of Earth at the given latitude
*/
function ip_geoloc_earth_radius($latitude) {
$lat = deg2rad($latitude);
$x = cos($lat) / ip_geoloc_earth_radius_semimajor();
$y = sin($lat) / ip_geoloc_earth_radius_semiminor();
return 1.0 / sqrt($x * $x + $y * $y);
}
/**
* Get semimajor radius.
*/
function ip_geoloc_earth_radius_semimajor() {
return 6378137.0;
}
/**
* Get semiminor radius.
*/
function ip_geoloc_earth_radius_semiminor() {
return ip_geoloc_earth_radius_semimajor() * (1.0 - ip_geoloc_earth_flattening());
}
/**
* Flatten the earth.
*/
function ip_geoloc_earth_flattening() {
return 1.0 / 298.257223563;
}
/**
* Return a random point within the circle centered on the supplied location.
* @param array $location, holding 'lat' and 'lon' entries
* @param float $radius, expressed in meters, should be greater than zero
* @return array with randomly displaced 'lat' and 'lon'
*
* From: http://stackoverflow.com/a/5838991/5350316
*/
function ip_geoloc_add_random_displacement(&$location, $radius_km) {
$a = ip_geoloc_random(0, 1);
$b = ip_geoloc_random(0, 1);
if ($b < $a) {
// Swap
$c = $a;
$a = $b;
$b = $c;
}
$angle = 2 * pi() * $a / $b;
// Approximate km to degrees conversion
// See http://stackoverflow.com/questions/1253499/simple-calculations-for-working-with-lat-lon-km-distance
$radius = $radius_km / 111000;
$location['lat'] += $b * $radius * cos($angle);
$location['lon'] += $b * $radius * sin($angle);
}
/**
* Generate a random number uniformly distributed between supplied limits.
*
* @param float $min
* @param float $max
* @return float
*
* @ee http://php.net/manual/en/function.mt-getrandmax.php
*/
function ip_geoloc_random($min = 0, $max = 1) {
return $min + mt_rand() / mt_getrandmax() * ($max - $min);
}Functions
Name |
Description |
|---|---|
| ip_geoloc_add_random_displacement | Return a random point within the circle centered on the supplied location. |
| ip_geoloc_center_of_locations | Calculate the center of the supplied locations using one of two algorithms. |
| ip_geoloc_distance | Returns the distance (in meters) between two points on the earth's surface. |
| ip_geoloc_earth_distance | Returns the distance between two points on the earth's surface. |
| ip_geoloc_earth_flattening | Flatten the earth. |
| ip_geoloc_earth_radius | Get radius of the Earth at a given latitude. |
| ip_geoloc_earth_radius_semimajor | Get semimajor radius. |
| ip_geoloc_earth_radius_semiminor | Get semiminor radius. |
| ip_geoloc_get_address | Returns the formatted address reverse-geocoded from the supplied lat,long. |
| ip_geoloc_get_current_location | Uses AJAX to return in $_POST info about the visitor's current location. |
| ip_geoloc_get_location_by_ip | Returns the location details associated with the supplied IP address. |
| ip_geoloc_get_visitor_location | Return the visitor's location as currently stored in the session. |
| ip_geoloc_output_map | Outputs an HTML div placeholder into which will be injected a map. |
| ip_geoloc_output_map_current_location | Outputs an HTML div placeholder into which is injected a map. |
| ip_geoloc_output_map_multi_location | Outputs an HTML div placeholder into which will be injected a Google map. |
| ip_geoloc_output_map_multi_visitor | Outputs an HTML div placeholder into which will be injected a map. |
| ip_geoloc_random | Generate a random number uniformly distributed between supplied limits. |
| ip_geoloc_reverse_geocode | Uses the Google webservice to retrieve address information based on lat/long. |
| ip_geoloc_store_location | Store the supplied IP geolocation info on the database. |
Constants
|
Name |
Description |
|---|---|
| IP_GEOLOC_GOOGLE_MAPS | |
| IP_GEOLOC_GOOGLE_MAPS_SERVER |