Fix email notification SMTP to support STARTTLS (port 587)

[bar-jpg]

Summary

Fix email notification SMTP to support STARTTLS (port 587)

Analysis

Let me search the codebase to find the email notification implementation in workflows.You've found a real bug. Here's a complete breakdown:

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Root Cause: Hardcoded SMTP_SSL — No STARTTLS Support

Both v1 and v2 of the Email Notification block always use smtplib.SMTP_SSL, which is correct only for port 465 (implicit SSL). They have zero support for STARTTLS (port 587), which is what most modern SMTP servers (Office 365, AWS SES, Postfix, SendGrid, etc.) require.

The two connection models:

Port	Protocol	Correct smtplib call
465	Implicit SSL	smtplib.SMTP_SSL(host, 465) ✅
587	STARTTLS	smtplib.SMTP(host, 587) + .starttls() ✅
25	Plaintext	smtplib.SMTP(host, 25)

Affected code

v1 — establish_smtp_connection (line 494–496):

@contextmanager
def establish_smtp_connection(smtp_server, smtp_port) -> Generator[smtplib.SMTP_SSL, None, None]:
    context = ssl.create_default_context()
    with smtplib.SMTP_SSL(smtp_server, smtp_port, context=context) as server:  # ❌ always SSL
        yield server

v2 — _send_email_using_smtp_server_v2 (line 1057–1059):

# Same pattern, same bug, copy-pasted inside _send_email_using_smtp_server_v2
with smtplib.SMTP_SSL(smtp_server, smtp_port, context=context) as server:  # ❌ always SSL

Also note: the smtp_port field description in both manifests explicitly says 587 for TLS (not supported) — so this is a known limitation that was never fixed.

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The Fix

The establish_smtp_connection helper needs to detect the port and pick the right connection strategy:

In v1.py — replace establish_smtp_connection:

@contextmanager
def establish_smtp_connection(
    smtp_server: str, smtp_port: int
) -> Generator[smtplib.SMTP, None, None]:
    context = ssl.create_default_context()
    if smtp_port == 465:
        # Implicit SSL
        with smtplib.SMTP_SSL(smtp_server, smtp_port, context=context) as server:
            yield server
    else:
        # STARTTLS (port 587, 25, or any non-465 port)
        with smtplib.SMTP(smtp_server, smtp_port) as server:
            server.ehlo()
            server.starttls(context=context)
            server.ehlo()
            yield server

In v2.py — apply the same fix to the establish_smtp_connection nested function inside _send_email_using_smtp_server_v2 (lines ~1057–1060), and also update the manifest description to remove the 587 (not supported) wording.

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Workaround (for users right now)

If your SMTP provider supports it, use port 465 instead of 587. That's the only port that currently works. If your server mandates 587 (e.g., Office 365, some corporate SMTP relays), you're blocked until the fix is deployed.

Files Changed

• inference/core/workflows/core_steps/sinks/email_notification/v1.py
• inference/core/workflows/core_steps/sinks/email_notification/v2.py

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[grzegorz-roboflow]

@bar-jpg, can you double-check if the change was committed correctly?