* @copyright 2011 Services_Libravatar committers.
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @link http://pear.php.net/package/Services_Libravatar
* @since File available since Release 0.1.0
*/
/**
* PHP support for the Libravatar.org service.
*
* Using this class is easy. After including or requiring
* Services/Libravatar.php simply do:
*
* $libravatar = new Services_Libravatar();
* $url = $libravatar->getUrl('melissa@meldraweb.com');
*
*
* This would populate $url with the string:
*
* http://cdn.libravatar.org/avatar/4db84629c121f2d443d33bdb9fd149bc
*
*
* A complicated lookup using all the options is:
*
* $libravatar = new Services_Libravatar();
* $libravatar->setSize(40);
* $libravatar->setAlgorithm('sha256');
* $libravatar->setHttps(true);
* $libravatar->setDefault(
* 'http://upload.wikimedia.org/wikipedia/commons/a/af/Tux.png'
* );
* $url = $libravatar->getUrl('melissa@meldraweb.com');
*
*
* @category Services
* @package Services_Libravatar
* @author Melissa Draper
* @copyright 2011 Services_Libravatar committers.
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @version Release: 0.2.1
* @link http://pear.php.net/package/Services_Libravatar
* @since Class available since Release 0.1.0
*/
class Services_Libravatar
{
/**
* Hashing algorithm to use
*
* @var string
* @see processAlgorithm()
* @see setAlgorithm()
*/
protected $algorithm = 'md5';
/**
* Default image URL to use
*
* @var string
* @see processDefault()
* @see setDefault()
*/
protected $default;
/**
* If HTTPS URLs should be used
*
* @var boolean
* @see detectHttps()
* @see setHttps()
*/
protected $https;
/**
* Image size in pixels
*
* @var integer
* @see processSize()
* @see setSize()
*/
protected $size;
/**
* Composes a URL for the identifier and options passed in
*
* Compose a full URL as specified by the Libravatar API, based on the
* email address or openid URL passed in, and the options specified.
*
* @param string $identifier a string of either an email address
* or an openid url
* @param array $options an array of (bool) https, (string) algorithm
* (string) size, (string) default.
* See the set* methods.
*
* @return string A string of a full URL for an avatar image
*
* @since Method available since Release 0.2.0
* @deprecated Use getUrl() instead
*/
public function url($identifier, $options = array())
{
return $this->getUrl($identifier, $options);
}
/**
* Composes a URL for the identifier and options passed in
*
* Compose a full URL as specified by the Libravatar API, based on the
* email address or openid URL passed in, and the options specified.
*
* @param string $identifier a string of either an email address
* or an openid url
* @param array $options an array of (bool) https, (string) algorithm
* (string) size, (string) default.
* See the set* methods.
*
* @return string A string of a full URL for an avatar image
*
* @since Method available since Release 0.2.0
* @throws InvalidArgumentException When an invalid option is passed
*/
public function getUrl($identifier, $options = array())
{
// If no identifier has been passed, set it to a null.
// This way, there'll always be something returned.
if (!$identifier) {
$identifier = null;
} else {
$identifier = $this->normalizeIdentifier($identifier);
}
// Load all options
$options = $this->checkOptionsArray($options);
$https = $this->https;
if (isset($options['https'])) {
$https = (bool)$options['https'];
}
$algorithm = $this->algorithm;
if (isset($options['algorithm'])) {
$algorithm = $this->processAlgorithm($options['algorithm']);
}
$default = $this->default;
if (isset($options['default'])) {
$default = $this->processDefault($options['default']);
}
$size = $this->size;
if (isset($options['size'])) {
$size = $this->processSize($options['size']);
}
$identifierHash = $this->identifierHash($identifier, $algorithm);
// Get the domain so we can determine the SRV stuff for federation
$domain = $this->domainGet($identifier);
// If https has been specified in $options, make sure we make the
// correct SRV lookup
$service = $this->srvGet($domain, $https);
$protocol = $https ? 'https' : 'http';
$params = array();
if ($size !== null) {
$params['size'] = $size;
}
if ($default !== null) {
$params['default'] = $default;
}
$paramString = '';
if (count($params) > 0) {
$paramString = '?' . http_build_query($params);
}
// Compose the URL from the pieces we generated
$url = $protocol . '://' . $service . '/avatar/' . $identifierHash
. $paramString;
// Return the URL string
return $url;
}
/**
* Checks the options array and verify that only allowed options are in it.
*
* @param array $options Array of options for getUrl()
*
* @return void
* @throws Exception When an invalid option is used
*/
protected function checkOptionsArray($options)
{
//this short options are deprecated!
if (isset($options['s'])) {
$options['size'] = $options['s'];
unset($options['s']);
}
if (isset($options['d'])) {
$options['default'] = $options['d'];
unset($options['d']);
}
$allowedOptions = array(
'algorithm' => true,
'default' => true,
'https' => true,
'size' => true,
);
foreach ($options as $key => $value) {
if (!isset($allowedOptions[$key])) {
throw new InvalidArgumentException(
'Invalid option in array: ' . $key
);
}
}
return $options;
}
/**
* Normalizes the identifier (E-mail address or OpenID)
*
* @param string $identifier E-Mail address or OpenID
*
* @return string Normalized identifier
*/
protected function normalizeIdentifier($identifier)
{
if (filter_var($identifier, FILTER_VALIDATE_EMAIL)) {
return strtolower($identifier);
} else {
return self::normalizeOpenId($identifier);
}
}
/**
* Create a hash of the identifier.
*
* Create a hash of the email address or openid passed in. Algorithm
* used for email address ONLY can be varied. Either md5 or sha256
* are supported by the Libravatar API. Will be ignored for openid.
*
* @param string $identifier A string of the email address or openid URL
* @param string $hash A string of the hash algorithm type to make
* Uses the php implementation of hash()
* MD5 preferred for Gravatar fallback
*
* @return string A string hash of the identifier.
*
* @since Method available since Release 0.1.0
*/
protected function identifierHash($identifier, $hash = 'md5')
{
if (filter_var($identifier, FILTER_VALIDATE_EMAIL) || $identifier === null) {
// If email, we can select our algorithm. Default to md5 for
// gravatar fallback.
return hash($hash, $identifier);
}
//no email, so the identifier has to be an OpenID
return hash('sha256', $identifier);
}
/**
* Normalizes an identifier (URI or XRI)
*
* @param mixed $identifier URI or XRI to be normalized
*
* @return string Normalized Identifier.
* Empty string when the OpenID is invalid.
*
* @internal Adapted from OpenID::normalizeIdentifier()
*/
public static function normalizeOpenId($identifier)
{
// XRI
if (preg_match('@^xri://@i', $identifier)) {
return preg_replace('@^xri://@i', '', $identifier);
}
if (in_array($identifier[0], array('=', '@', '+', '$', '!'))) {
return $identifier;
}
// URL
if (!preg_match('@^http[s]?://@i', $identifier)) {
$identifier = 'http://' . $identifier;
}
if (strpos($identifier, '/', 8) === false) {
$identifier .= '/';
}
if (!filter_var($identifier, FILTER_VALIDATE_URL)) {
return '';
}
$parts = parse_url($identifier);
$parts['scheme'] = strtolower($parts['scheme']);
$parts['host'] = strtolower($parts['host']);
//http://openid.net/specs/openid-authentication-2_0.html#normalization
return $parts['scheme'] . '://'
. (isset($parts['user']) ? $parts['user'] : '')
. (isset($parts['pass']) ? ':' . $parts['pass'] : '')
. (isset($parts['user']) || isset($parts['pass']) ? '@' : '')
. $parts['host']
. (
(isset($parts['port'])
&& $parts['scheme'] === 'http' && $parts['port'] != 80)
|| (isset($parts['port'])
&& $parts['scheme'] === 'https' && $parts['port'] != 443)
? ':' . $parts['port'] : ''
)
. $parts['path']
. (isset($parts['query']) ? '?' . $parts['query'] : '');
//leave out fragment as requested by the spec
}
/**
* Grab the domain from the identifier.
*
* Extract the domain from the Email or OpenID.
*
* @param string $identifier A string of the email address or openid URL
*
* @return string A string of the domain to use
*
* @since Method available since Release 0.1.0
*/
protected function domainGet($identifier)
{
if ($identifier === null) {
return null;
}
// What are we, email or openid? Split ourself up and get the
// important bit out.
if (filter_var($identifier, FILTER_VALIDATE_EMAIL)) {
$email = explode('@', $identifier);
return $email[1];
}
//OpenID
$url = parse_url($identifier);
$domain = $url['host'];
if (isset($url['port']) && $url['scheme'] === 'http'
&& $url['port'] != 80
|| isset($url['port']) && $url['scheme'] === 'https'
&& $url['port'] != 443
) {
$domain .= ':' . $url['port'];
}
return $domain;
}
/**
* Get the target to use.
*
* Get the SRV record, filtered by priority and weight. If our domain
* has no SRV records, fall back to Libravatar.org
*
* @param string $domain A string of the domain we extracted from the
* provided identifier with domainGet()
* @param boolean $https Whether or not to look for https records
*
* @return string The target URL.
*
* @since Method available since Release 0.1.0
*/
protected function srvGet($domain, $https = false)
{
// Are we going secure? Set up a fallback too.
if (isset($https) && $https === true) {
$subdomain = '_avatars-sec._tcp.';
$fallback = 'seccdn.';
} else {
$subdomain = '_avatars._tcp.';
$fallback = 'cdn.';
}
// Lets try get us some records based on the choice of subdomain
// and the domain we had passed in.
$srv = @dns_get_record($subdomain . $domain, DNS_SRV);
// Did we get anything? No?
if (empty($srv)) {
// Then let's try Libravatar.org.
return $fallback . 'libravatar.org';
}
// Sort by the priority. We must get the lowest.
usort($srv, array($this, 'comparePriority'));
$top = $srv[0];
$sum = 0;
// Try to adhere to RFC2782's weighting algorithm, page 3
// "arrange all SRV RRs (that have not been ordered yet) in any order,
// except that all those with weight 0 are placed at the beginning of
// the list."
shuffle($srv);
$srvs = array();
foreach ($srv as $s) {
if ($s['weight'] == 0) {
array_unshift($srvs, $s);
} else {
array_push($srvs, $s);
}
}
foreach ($srvs as $s) {
if ($s['pri'] == $top['pri']) {
// "Compute the sum of the weights of those RRs"
$sum += (int) $s['weight'];
// "and with each RR associate the running sum in the selected
// order."
$pri[$sum] = $s;
}
}
// "Then choose a uniform random number between 0 and the sum computed
// (inclusive)"
$random = rand(0, $sum);
// "and select the RR whose running sum value is the first in the selected
// order which is greater than or equal to the random number selected"
foreach ($pri as $k => $v) {
if ($k >= $random) {
return $v['target'];
}
}
}
/**
* Sorting function for record priorities.
*
* @param mixed $a A mixed value passed by usort()
* @param mixed $b A mixed value passed by usort()
*
* @return mixed The result of the comparison
*
* @since Method available since Release 0.1.0
*/
protected function comparePriority($a, $b)
{
return $a['pri'] - $b['pri'];
}
/**
* Automatically set the https option depending on the current connection
* value.
*
* If the current connection is HTTPS, the https options is activated.
* If it is not HTTPS, the https option is deactivated.
*
* @return self
*/
public function detectHttps()
{
$this->setHttps(
isset($_SERVER['HTTPS']) && $_SERVER['HTTPS']
);
return $this;
}
/**
* Verify and cast the email address hashing algorithm to use.
*
* @param string $algorithm Algorithm to use, "sha256" or "md5".
*
* @return string Algorithm
*
* @throws InvalidArgumentException When an unsupported algorithm is given
*/
protected function processAlgorithm($algorithm)
{
$algorithm = (string)$algorithm;
if ($algorithm !== 'md5' && $algorithm !== 'sha256') {
throw new InvalidArgumentException(
'Only md5 and sha256 hashing supported'
);
}
return $algorithm;
}
/**
* Verify and cast the default URL to use when no avatar image can be found.
* If none is set, the libravatar logo is returned.
*
* @param string $url Full URL to use OR one of the following:
* - "404" - give a "404 File not found" instead of an image
* - "mm"
* - "identicon"
* - "monsterid"
* - "wavatar"
* - "retro"
*
* @return string Default URL
*
* @throws InvalidArgumentException When an invalid URL is given
*/
protected function processDefault($url)
{
if ($url === null) {
return $url;
}
$url = (string)$url;
switch ($url) {
case '404':
case 'mm':
case 'identicon':
case 'monsterid':
case 'wavatar':
case 'retro':
case 'robohash':
case 'pagan':
break;
default:
$valid = filter_var($url, FILTER_VALIDATE_URL);
if (!$valid) {
throw new InvalidArgumentException('Invalid default avatar URL');
}
break;
}
return $url;
}
/**
* Verify and cast the required size of the images.
*
* @param integer $size Size (width and height in pixels) of the image.
* NULL for the default width.
*
* @return integer Size
*
* @throws InvalidArgumentException When a size <= 0 is given
*/
protected function processSize($size)
{
if ($size === null) {
return $size;
}
$size = (int)$size;
if ($size <= 0) {
throw new InvalidArgumentException('Size has to be larger than 0');
}
return (int)$size;
}
/**
* Set the email address hashing algorithm to use.
* To keep gravatar compatibility, use "md5".
*
* @param string $algorithm Algorithm to use, "sha256" or "md5".
*
* @return self
* @throws InvalidArgumentException When an unsupported algorithm is given
*/
public function setAlgorithm($algorithm)
{
$this->algorithm = $this->processAlgorithm($algorithm);
return $this;
}
/**
* Set the default URL to use when no avatar image can be found.
* If none is set, the gravatar logo is returned.
*
* @param string $url Full URL to use OR one of the following:
* - "404" - give a "404 File not found" instead of an image
* - "mm"
* - "identicon"
* - "monsterid"
* - "wavatar"
* - "retro"
*
* @return self
* @throws InvalidArgumentException When an invalid URL is given
*/
public function setDefault($url)
{
$this->default = $this->processDefault($url);
return $this;
}
/**
* Set if HTTPS URLs shall be returned.
*
* @param boolean $useHttps If HTTPS url shall be returned
*
* @return self
*
* @see detectHttps()
*/
public function setHttps($useHttps)
{
$this->https = (bool)$useHttps;
return $this;
}
/**
* Set the required size of the images.
* Every avatar image is square sized, which means you need to set only number.
*
* @param integer $size Size (width and height) of the image
*
* @return self
* @throws InvalidArgumentException When a size <= 0 is given
*/
public function setSize($size)
{
$this->size = $this->processSize($size);
return $this;
}
}
/*
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* c-hanging-comment-ender-p: nil
* End:
*/