Jul 28 - Update the demo request button, and add demo registration page

mailer.py

@@ -0,0 +1,84 @@
+"""Minimal SMTP sender for owner/customer notifications.
+
+Deliberately stdlib-only (smtplib + email) — no new dependency, no queue, no
+broker. Mail is sent on a daemon thread so a slow or dead SMTP host never makes
+the visitor wait, and a failure is logged rather than raised: the demo request
+is already committed to the database by the time we get here, so the owner can
+always see it in /admin/demos even if mail is misconfigured.
+"""
+
+import logging
+import smtplib
+import threading
+from email.message import EmailMessage
+from email.utils import formataddr, parseaddr
+
+mail_log = logging.getLogger("jqc.mail")
+
+
+def mail_enabled(config):
+    """Mail can only go out with a host and a From address configured."""
+    return bool(config.get("SMTP_HOST") and config.get("MAIL_FROM"))
+
+
+def _clean_header(value):
+    """Strip CR/LF so a user-supplied name can't inject extra headers."""
+    return " ".join(str(value or "").split())[:200]
+
+
+def send_email(config, to, subject, body, reply_to=None, reply_name=None):
+    """Send one plain-text mail. Returns True on success, False otherwise.
+    Never raises — callers treat mail as best-effort."""
+    if not mail_enabled(config) or not to:
+        mail_log.info("Mail skipped (SMTP not configured): %s", _clean_header(subject))
+        return False
+
+    prefix = config.get("MAIL_SUBJECT_PREFIX", "")
+    msg = EmailMessage()
+    msg["Subject"] = _clean_header(f"{prefix} {subject}".strip())
+    msg["From"] = config["MAIL_FROM"]
+    msg["To"] = to
+    if reply_to:
+        addr = parseaddr(_clean_header(reply_to))[1]
+        if addr:
+            msg["Reply-To"] = formataddr((_clean_header(reply_name), addr))
+    msg.set_content(body)
+
+    host = config["SMTP_HOST"]
+    port = config.get("SMTP_PORT", 587)
+    timeout = config.get("SMTP_TIMEOUT", 20)
+    try:
+        if config.get("SMTP_USE_SSL"):
+            server = smtplib.SMTP_SSL(host, port, timeout=timeout)
+        else:
+            server = smtplib.SMTP(host, port, timeout=timeout)
+        with server:
+            server.ehlo()
+            if config.get("SMTP_USE_TLS") and not config.get("SMTP_USE_SSL"):
+                server.starttls()
+                server.ehlo()
+            if config.get("SMTP_USER"):
+                server.login(config["SMTP_USER"], config.get("SMTP_PASSWORD", ""))
+            server.send_message(msg)
+        mail_log.info("Mail sent to %s: %s", to, msg["Subject"])
+        return True
+    except Exception as exc:  # noqa: BLE001 - mail must never break the request
+        mail_log.error("Mail to %s failed: %s", to, exc)
+        return False
+
+
+def send_email_async(config, to, subject, body, reply_to=None, reply_name=None):
+    """Fire-and-forget wrapper. `config` is copied to a plain dict first so the
+    thread never touches the Flask app/request context."""
+    cfg = {k: config.get(k) for k in (
+        "SMTP_HOST", "SMTP_PORT", "SMTP_USER", "SMTP_PASSWORD", "SMTP_USE_TLS",
+        "SMTP_USE_SSL", "SMTP_TIMEOUT", "MAIL_FROM", "MAIL_SUBJECT_PREFIX",
+    )}
+    thread = threading.Thread(
+        target=send_email,
+        args=(cfg, to, subject, body),
+        kwargs={"reply_to": reply_to, "reply_name": reply_name},
+        daemon=True,
+    )
+    thread.start()
+    return thread