New internal/mailer/ package:
- Sender interface with two impls: SMTPSender (production, reads
smtp_config at send time so admin edits apply without restart;
uses stdlib net/smtp + STARTTLS) and FakeSender (test/concurrent-
safe call recorder).
- Embedded text + HTML templates for the password reset email,
rendered via stdlib text/template + html/template. The HTML
uses the FabledSword forest-teal accent color.
- ErrNotConfigured surfaces when smtp_config.enabled is false or
required fields are empty; callers like the future forgot-password
handler will treat this as "log and pretend success" to avoid
user-enumeration leaks.
Three admin endpoints under RequireAdmin:
- GET /api/admin/smtp-config — returns the singleton; password
field is masked ("***" or "").
- PUT /api/admin/smtp-config — updates settings. Validates
host + from_address are non-empty when enabled=true. Empty
password in the request preserves the stored value (so the
operator doesn't have to re-enter it on every save).
- POST /api/admin/smtp-config/test — sends a real test email to
the calling admin's email. 400 if admin has no email; 500 with
the error message on send failure (so the operator can debug
config without grep-then-trace through logs).
Tests cover the password-mask, password-preservation-on-empty,
enabled-requires-host-and-from validation, and the no-email-on-file
rejection. Mailer unit tests cover the fake recorder and template
rendering. The "real SMTP send" path needs a live server and isn't
covered in CI; the FakeSender covers that role for downstream tests.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
bvandeusen
aa67a09b80