Implementing Gravatar into custom Commenting System - php

Question

I'm in the process of coding my very first blog. With the help of various tutorials, and other forums I have managed to gather a semi-working code.
Right now I have a code that takes and displays the comment, but the problem is I wish to display Gravatars beside each comment. I was just wondering how exactly I would go about implementing the code that they provided on their website.
Here is my current comment form:
<?php
}
$commenttimestamp = strtotime("now");
$sql = "SELECT * FROM php_blog_comments WHERE entry='$id' ORDER BY timestamp";
$result = mysql_query ($sql) or print ("Can't select comments from table php_blog_comments.<br />" . $sql . "<br />" . mysql_error());
while($row = mysql_fetch_array($result)) {
$timestamp = date("l F d Y", $row['timestamp']);
printf("<hr />");
print("<p>" . stripslashes($row['comment']) . "</p>");
printf("<p>Comment by %s # %s</p>", stripslashes($row['url']), stripslashes($row['name']), $timestamp);
printf("<hr />");
}
?>
<form method="post" action="process.php">
<p><input type="hidden" name="entry" id="entry" value="<?php echo $id; ?>" />
<input type="hidden" name="timestamp" id="timestamp" value="<?php echo $commenttimestamp; ?>">
<strong><label for="name">Name:</label></strong> <input type="text" name="name" id="name" size="25" /><br />
<strong><label for="email">E-mail:</label></strong> <input type="text" name="email" id="email" size="25" /><br />
<strong><label for="url">URL:</label></strong> <input type="text" name="url" id="url" size="25" value="http://" /><br />
<strong><label for="comment">Comment:</label></strong><br />
<textarea cols="25" rows="5" name="comment" id="comment"></textarea></p>
<p><input type="submit" name="submit_comment" id="submit_comment" value="Add Comment" /></p>
</form>
If you wish for me to post the php that processes each comment here as well just ask below.
My code now:
<?php
function get_gravatar( $email, $s = 80, $d = 'mm', $r = 'g', $img = false, $atts = array() ) {
$url = 'http://www.gravatar.com/avatar/';
$url .= md5( strtolower( trim( $email ) ) );
$url .= "?s=$s&d=$d&r=$r";
if ( $img ) {
$url = '<img src="' . $url . '"';
foreach ( $atts as $key => $val )
$url .= ' ' . $key . '="' . $val . '"';
$url .= ' />';
}
return $url;
}
}
$commenttimestamp = strtotime("now");
$sql = "SELECT * FROM php_blog_comments WHERE entry='$id' ORDER BY timestamp";
$result = mysql_query ($sql) or print ("Can't select comments from table php_blog_comments.<br />" . $sql . "<br />" . mysql_error());
while($row = mysql_fetch_array($result)) {
$timestamp = date("l F d Y", $row['timestamp']);
printf("<hr />");
print("<p>" . stripslashes($row['comment']) . "</p>");
printf("<p>Comment by %s # %s</p>", stripslashes($row['url']), stripslashes($row['name']), $timestamp);
echo $imagetag = "<img src='" . get_gravatar($email) . "' />";
printf("<hr />");
}
?>

Answer 1

You want an image tag whose src comes from the gravatar function.
Something like:
$imagetag = "<img src='" . get_gravatar($email_address) . ' />";
(You'll need to echo this variable where you want it to display.)
The only required parameter of the get_gravatar function is the email address, so just pass this to get_gravatar and you get the url of the gravatar image.

Answer 2

You also may use the Libravatar service that provides a gravatar-compatible but open source and federated alternative.
It has a nice PHP library - Services_Libravatar - that's easy to use:
<?php
require_once 'Services/Libravatar.php';
$sla = new Services_Libravatar();
$imgUrl = $sla->getUrl('foo#example.org');