feat(api): add domain-routed fallback email provider (#3506)

deploy/self-hosting/.env.example

@@ -325,6 +325,15 @@ FLUXER_EMAIL_SMTP_TLS_MODE=
 # The older switch, read only while the mode above is empty. true is implicit
 # and false is opportunistic.
 #FLUXER_EMAIL_SMTP_SECURE=false
+# A second SMTP provider for mail to the listed recipient domains, comma
+# separated and matched exactly. Everything else goes through the provider
+# above. The port falls back to 587 and the mode works like the one above.
+#FLUXER_EMAIL_FALLBACK_DOMAINS=gmail.com,googlemail.com
+#FLUXER_EMAIL_FALLBACK_SMTP_HOST=
+#FLUXER_EMAIL_FALLBACK_SMTP_PORT=587
+#FLUXER_EMAIL_FALLBACK_SMTP_USERNAME=
+#FLUXER_EMAIL_FALLBACK_SMTP_PASSWORD=
+#FLUXER_EMAIL_FALLBACK_SMTP_TLS_MODE=
 #FLUXER_EMAIL_WEBHOOK_SECRET=
 
 FLUXER_DISCOVERY_ENABLED=true

deploy/self-hosting/docker-compose.yml

@@ -126,6 +126,12 @@ x-fluxer-env: &fluxer-env
   FLUXER_EMAIL_SMTP_PASSWORD: ${FLUXER_EMAIL_SMTP_PASSWORD:-}
   FLUXER_EMAIL_SMTP_TLS_MODE: ${FLUXER_EMAIL_SMTP_TLS_MODE:-}
   FLUXER_EMAIL_SMTP_SECURE: ${FLUXER_EMAIL_SMTP_SECURE:-}
+  FLUXER_EMAIL_FALLBACK_DOMAINS: ${FLUXER_EMAIL_FALLBACK_DOMAINS:-}
+  FLUXER_EMAIL_FALLBACK_SMTP_HOST: ${FLUXER_EMAIL_FALLBACK_SMTP_HOST:-}
+  FLUXER_EMAIL_FALLBACK_SMTP_PORT: ${FLUXER_EMAIL_FALLBACK_SMTP_PORT:-}
+  FLUXER_EMAIL_FALLBACK_SMTP_USERNAME: ${FLUXER_EMAIL_FALLBACK_SMTP_USERNAME:-}
+  FLUXER_EMAIL_FALLBACK_SMTP_PASSWORD: ${FLUXER_EMAIL_FALLBACK_SMTP_PASSWORD:-}
+  FLUXER_EMAIL_FALLBACK_SMTP_TLS_MODE: ${FLUXER_EMAIL_FALLBACK_SMTP_TLS_MODE:-}
 
   FLUXER_STRIPE_ENABLED: ${FLUXER_STRIPE_ENABLED:-}
   FLUXER_STRIPE_SECRET_KEY: ${FLUXER_STRIPE_SECRET_KEY:-}