Retrieve full email address from string - php

Question

I'm currently building a Slack bot using Laravel, and one of the features is that it can receive an email address and send a message to it.
The issue is that email addresses (e.g bob#example.com) come through as <mailto:bob#example.com|bob#example.com> from Slack.
I currently have a function that retrieves the email from this:
public function getEmail($string)
{
$pattern = '/[a-z0-9_\-\+]+#[a-z0-9\-]+\.([a-z]{2,3})(?:\.[a-z]{2})?/i';
preg_match_all($pattern, $string, $matches);
$matches = array_filter($matches);
return $matches[0][0];
}
This seemed to be working fine with email addresses like bob#example.com, however it seems to fail when working with email addresses like bob.jones#example.com (which would come through as <mailto:bob.jones#example.com|bob.jones#example.com>.
In these cases, the function is returning jones#example.com as the email address.
I'm not great with regex, but is there something else I could use/change in my pattern, or a better way to fetch the email address from the string provided by Slack?

Answer 1

Could always take regex out of the equation if you know that's always the format it'll be in:
$testString = '<mailto:bob#example.com|bob#example.com>';
$testString = str_replace(['<mailto:', '>'], '', $testString);
$addresses = explode('|', $testString);
echo $addresses[0];

Answer 2

This method will do the job and you avoid to have regular expressions. and make sure the email being returned is a real email address by validating it with php functions.
function getEmailAddress($string)
{
$string = trim($string, '<>');
$args = explode('|', $string);
foreach ($args as $_ => $val) {
if(filter_var($val, FILTER_VALIDATE_EMAIL) !== false) {
return $val;
}
}
return null;
}
echo getEmailAddress('<mailto:bob#example.com|bob#example.com>');
Output
bob#example.com

Answer 3

You know the strings containing the e-mail address will always be of the form <mailto:bob#example.com|bob#example.com>, so use that. Specifically, you know the string will start with <mailto:, will contain a |, and will end with >.
An added difficulty though, is that the local part of an e-mail address may contain a pipe character as well, but the domain may not; see the following question.
What characters are allowed in an email address?
public function getEmail($string)
{
$pattern = '/^<mailto:([^#]+#[^|]+)|(.*)>$/i';
preg_match_all($pattern, $string, $matches);
$matches = array_filter($matches);
return $matches[1][0];
}
This matches the full line from beginning to end, but we capture the e-mail address within the first set of parentheses. $matches[1] contains all matches from the first capturing parentheses. You could use preg_match instead, since you're not looking for all matches, just the first one.