Gitea Mail Error: Fixing The Angle Bracket Issue

Hey guys, have you ever run into a snag while setting up email notifications in Gitea? Specifically, have you seen the dreaded "double encapsulation of recipient in angle brackets" error? It's a real head-scratcher, but don't worry, we're going to dive deep into this issue. We'll explore the problem, dissect the error messages, and, most importantly, find a way to fix it. This guide is tailored for those of you who've compiled Gitea from source, using versions like 1.25.1. Let's get started!

Understanding the Problem: The Angle Bracket Dilemma

So, what's this whole angle bracket thing about? Well, when Gitea tries to send an email, it sometimes messes up the recipient's address. Instead of the standard format, you might see something like <<email@example.com>> in the mail logs. That extra set of angle brackets? That's the problem. The correct format should just be <email@example.com>. This mistake confuses the mail server, which then spits back an error. Specifically, the error message often reads "501 5.1.3 Recipient address syntax error." This means the mail server couldn't understand the email address format, and the email wasn't sent.

This issue usually pops up when Gitea uses sendmail to send emails, as indicated in the provided configuration. If you're using sendmail, it's crucial to ensure that the email addresses are formatted correctly. The error stems from how Gitea, or rather the underlying mail library, is handling the recipient addresses when using sendmail. Essentially, it's wrapping the address in the angle brackets twice, which is incorrect. This double encapsulation breaks the email address syntax, leading to the "Recipient address syntax error."

This isn't just a random glitch; it's a specific issue related to how the email addresses are being processed before they are sent. It's important to understand this because the solution will revolve around correcting this address formatting. The root cause lies in the interaction between Gitea's mail handling code and the way the sendmail program expects the email addresses to be formatted. The sendmail program, a common utility for sending emails, has strict rules about how email addresses should look. When the email addresses are not correctly formatted, sendmail rejects them, and the mail fails to send.

The mail.log file is your best friend when troubleshooting this. Looking at the mail.log file, you'll see lines that clearly show the failed command. The key part of the error message is "RCPT TO:", followed by the incorrectly formatted email address. For example, you might see RCPT TO:<<email@example.com>>, highlighting the double angle brackets. This specific detail provides a clear clue about where the problem lies. The solution involves adjusting the configuration or potentially modifying the source code to ensure the email addresses are formatted correctly before being passed to sendmail. The focus will be on ensuring the email addresses are formatted properly when Gitea interacts with the mail server. This is the crux of the problem, and resolving it will involve modifying either the configuration or the source code to fix the email address formatting.

Decoding the Error Messages

Let's break down the error messages to understand them better. The primary error is "501 5.1.3 Recipient address syntax error." This message is a standard SMTP (Simple Mail Transfer Protocol) error code. The "501" indicates a general syntax error, and "5.1.3" pinpoints the problem: an issue with the recipient's address. In plain English, the mail server is telling you it can't send the email because it doesn't understand the recipient's email address.

This error directly points to the double angle brackets, or the way the email address is formatted. The format is invalid, and the server can't process it. The email system cannot determine who the email should be sent to due to the incorrect formatting of the recipient's address. To fix the issue, you must ensure the recipient's email address adheres to the correct syntax. The error is a sign that the recipient's email address is formatted incorrectly, thus preventing the email from being sent. It's a clear indicator that something's wrong with the way the email address is being handled. The crucial part of resolving this is ensuring the recipient's email address is formatted correctly before being passed to the mail server.

Furthermore, the mail.log file gives more clues. Look for lines that include RCPT TO:. This part of the log shows exactly what Gitea is trying to tell the mail server. If you see something like RCPT TO:<<email@example.com>>, it's a clear indicator of the double angle bracket problem. This helps to pinpoint the source of the issue. By examining this line, you can confirm that the double angle brackets are indeed the cause. The key is to check the mail.log to see the exact command Gitea is trying to execute. It allows you to see the email address format being used and confirm the presence of the double angle brackets. This information is vital to understanding the context of the error. Once you know the command that's failing, you can start to trace where the problem is arising within the Gitea configuration or source code.

Examining Your Gitea Configuration

Now, let's take a look at the gitea-config file. The important bits are under the [mailer] section. This section controls how Gitea sends emails. Here's a quick rundown of the relevant settings:

• ENABLED = true: This must be set to true to enable email notifications.
• PROTOCOL = sendmail: This specifies that Gitea uses the sendmail program to send emails. This is crucial since the problem is related to sendmail.
• SENDMAIL_PATH = /usr/sbin/sendmail: This is the path to the sendmail executable. Make sure this is correct on your system.
• SENDMAIL_ARGS = --: This is an essential setting. The -- argument prevents the email address from being interpreted as an option by sendmail.
• FROM = "Gitea" <gitea@example.com>: This sets the