read.markets/app/services/email_service.py
Giorgio Gilestro 6e7f57c6b2 phase G: data minimisation + passwordless auth + DeepSeek-first LLM
Server no longer holds portfolios. Holdings live in the browser
(localStorage); the server publishes an anonymous ticker_universe and a
gzipped /api/universe payload identical for every authenticated user, so
access patterns can't betray which tickers a user holds. AI commentary
is generated ephemerally from the browser-supplied pie and the cost
ledger row records no positions. Migrations 0009-0011 added the
universe table and dropped positions / portfolio_snapshots /
portfolios.

Authentication is now e-mail OTP only. Migration 0010 dropped
password_hash and email_verified (every active session is by
construction proof of email control). The /signup endpoint is gone;
signup and login share a single email-entry page. Email rendering is
HTML+plain-text multipart with a shared brand palette (app/branding.py)
asserted in sync with the CSS by a drift-detection test.

LLM provider defaults to DeepSeek-direct (cheaper, api.deepseek.com)
with OpenRouter as automatic fallback if DeepSeek fails. ai_log_job and
indicator_summary_job now iterate the two tones (NOVICE, INTERMEDIATE)
per cycle so the dashboard's tone toggle is instant; PROMPT_VERSION
bumped to 6 with an educational anti-TA / anti-gambling stance baked
into _CORE. NOVICE mode renders a curated glossary inline (CBOE VIX,
yield curve, HY OAS, etc.) with JS-positioned tooltips that survive
viewport edges and sticky bars. Model name and tokens hidden from the
user UI; still recorded in StrategicLog.model and AICall for admin.

Layout adds a sticky top nav, a sticky bottom markets bar (one chip per
exchange with status LED + headline index + 1d change), and
Phase H feedback reporting is queued in tasks/todo.md.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-18 14:16:57 +01:00

191 lines
7.2 KiB
Python

"""SMTP-backed transactional email.
Sends multipart/alternative: a plain-text body for accessibility / minimal
clients and an HTML body for richer rendering. Designed for cross-client
robustness:
- Inline styles on every element (Outlook desktop ignores <style> blocks).
- `<style>` block in <head> only carries the prefers-color-scheme media
query for clients that respect it (Apple Mail, Gmail web, Outlook.com).
- Light background by default — dark backgrounds are inconsistently
rendered across clients.
- 520-px max width, monospace stack with fallbacks, no external assets
(no remote images, no web fonts), so the email opens identically with
network off.
When SMTP_SERVER is empty, falls back to writing the payload to stdout —
convenient for local dev that doesn't want a mail server configured.
"""
from __future__ import annotations
from email.message import EmailMessage
import aiosmtplib
from app import branding
from app.config import get_settings
from app.logging import get_logger
log = get_logger("email")
class EmailSendError(RuntimeError):
"""Raised when SMTP submission fails. The caller should surface a
generic error to the user rather than the SMTP details."""
async def send_email(
to: str,
subject: str,
text_body: str,
html_body: str | None = None,
) -> None:
"""Send a (potentially multipart) email. `text_body` is required —
it's the fallback for clients that can't or won't render HTML."""
s = get_settings()
sender = s.SMTP_FROM or s.SMTP_USER or "noreply@cassandra.local"
msg = EmailMessage()
msg["From"] = sender
msg["To"] = to
msg["Subject"] = subject
msg.set_content(text_body)
if html_body:
msg.add_alternative(html_body, subtype="html")
if not s.SMTP_SERVER:
log.info(
"email.stdout_fallback", to=to, subject=subject,
text_preview=text_body[:120],
multipart=bool(html_body),
)
return
try:
await aiosmtplib.send(
msg,
hostname=s.SMTP_SERVER,
port=s.SMTP_PORT,
username=s.SMTP_USER or None,
password=s.SMTP_PASSWORD or None,
start_tls=s.SMTP_USE_TLS,
timeout=20,
)
log.info("email.sent", to=to, subject=subject)
except Exception as e:
log.error("email.send_failed", to=to, error=str(e)[:200])
raise EmailSendError(f"Failed to send email: {e}") from e
# ---------------------------------------------------------------------------
# OTP email rendering
# ---------------------------------------------------------------------------
_OTP_HTML_TEMPLATE = """\
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<meta name="color-scheme" content="light dark">
<meta name="supported-color-schemes" content="light dark">
<title>Your Cassandra sign-in code</title>
<style>
@media (prefers-color-scheme: dark) {{
body {{ background:{D_bg} !important; }}
.card {{ background:{D_surface} !important; border-color:{D_border} !important; }}
.h1 {{ color:{D_text} !important; }}
.muted {{ color:{D_muted} !important; }}
.lead {{ color:{D_text} !important; }}
.code {{ background:{D_bg} !important; color:{D_accent} !important;
border-color:{D_accent} !important; }}
.divider {{ border-color:{D_border} !important; }}
}}
@media (max-width: 540px) {{
.card {{ padding:24px 18px !important; }}
.code {{ font-size:26px !important; letter-spacing:0.3em !important; }}
}}
</style>
</head>
<body style="margin:0; padding:24px 12px; background:{L_bg}; font-family:{FONT_MONO}; color:{L_text}; -webkit-font-smoothing:antialiased;">
<div style="display:none; max-height:0; overflow:hidden; mso-hide:all; font-size:1px; line-height:1px; color:{L_bg};">
Your Cassandra sign-in code — {code} — expires in {ttl_minutes} minutes.
</div>
<table role="presentation" cellpadding="0" cellspacing="0" border="0" align="center" width="100%" style="max-width:520px; margin:0 auto; border-collapse:separate;">
<tr><td class="card" style="background:{L_surface}; border:1px solid {L_border}; padding:32px 28px;">
<div class="muted" style="font-size:11px; letter-spacing:0.32em; color:{L_muted}; text-transform:uppercase;">
&#9648;&nbsp;CASSANDRA
</div>
<div style="height:22px; line-height:22px; font-size:0;">&nbsp;</div>
<div class="h1" style="font-size:17px; font-weight:normal; color:{L_text}; letter-spacing:0.02em;">
Your sign-in code
</div>
<div style="height:16px; line-height:16px; font-size:0;">&nbsp;</div>
<div class="code" style="font-family:{FONT_MONO}; font-size:32px; letter-spacing:0.4em; text-align:center; padding:20px 12px; border:1px solid {L_accent}; background:{L_surface}; color:{L_accent}; user-select:all;">
{code}
</div>
<div style="height:18px; line-height:18px; font-size:0;">&nbsp;</div>
<div class="lead muted" style="font-size:13px; color:{L_muted}; line-height:1.6;">
This code expires in <span style="color:{L_text};">{ttl_minutes} minutes</span>.
If you didn&rsquo;t request it, you can safely ignore this email &mdash; no changes
will be made to any account.
</div>
<div style="height:26px; line-height:26px; font-size:0;">&nbsp;</div>
<div class="divider" style="border-top:1px solid {L_border};"></div>
<div style="height:14px; line-height:14px; font-size:0;">&nbsp;</div>
<div class="muted" style="font-size:10.5px; color:{L_dim}; letter-spacing:0.06em;">
Sent automatically by Cassandra &middot; do not reply
</div>
</td></tr>
</table>
</body>
</html>
"""
def _html_template_filled(code: str, ttl_minutes: int) -> str:
"""Substitute palette + content into the OTP HTML template."""
return _OTP_HTML_TEMPLATE.format(
code=code,
ttl_minutes=ttl_minutes,
FONT_MONO=branding.FONT_MONO,
**{f"L_{k.replace('-', '_')}": v for k, v in branding.LIGHT.items()},
**{f"D_{k.replace('-', '_')}": v for k, v in branding.DARK.items()},
)
_OTP_TEXT_TEMPLATE = """\
CASSANDRA — sign in
Your verification code:
{code}
This code expires in {ttl_minutes} minutes.
If you didn't request it, you can safely ignore this email — no changes
will be made to any account.
Sent automatically by Cassandra · do not reply
"""
def render_otp_email(code: str, ttl_minutes: int) -> tuple[str, str, str]:
"""Returns (subject, text_body, html_body).
Subject embeds the code so users can read it directly from the inbox
list without opening the message — common practice for OTP emails
(Notion, Substack). The lock-screen exposure tradeoff is minimal:
anyone with phone access who could see the notification could also
open the email."""
subject = f"Cassandra sign-in: {code}"
text = _OTP_TEXT_TEMPLATE.format(code=code, ttl_minutes=ttl_minutes)
html = _html_template_filled(code=code, ttl_minutes=ttl_minutes)
return subject, text, html
async def send_otp(to: str, code: str, ttl_minutes: int) -> None:
subject, text, html = render_otp_email(code, ttl_minutes)
await send_email(to, subject, text, html_body=html)