Enable optional SMTP setup

.env.sample

@@ -29,6 +29,9 @@ SECRET_DB_PASSWORD_VERSION=v1
 #NGINX_WEBSEED_CDN_URI=https://some-bucket.some-cdn.net
 
 ## E-mail settings
+#COMPOSE_FILE="compose.yml:compose.smtp.yml"
+#PEERTUBE_SMTP_ENABLED=1
+#SECRET_SMTP_PASSWORD_VERSION=v1
 #PEERTUBE_SMTP_HOSTNAME=postfix_relay_app
 #PEERTUBE_SMTP_PORT=25
 #PEERTUBE_SMTP_FROM=peertube@example.com # <= EDIT THIS

compose.smtp.yml

@@ -0,0 +1,19 @@
+---
+version: "3.8"
+
+services:
+  app:
+    environment:
+      - PEERTUBE_SMTP_DISABLE_STARTTLS
+      - PEERTUBE_SMTP_ENABLED
+      - PEERTUBE_SMTP_FROM
+      - PEERTUBE_SMTP_HOSTNAME
+      - PEERTUBE_SMTP_PORT
+      - PEERTUBE_SMTP_TLS
+    secrets:
+      - smtp_password
+
+secrets:
+  smtp_password:
+    name: ${STACK_NAME}_smtp_password_${SECRET_SMTP_PASSWORD_VERSION}
+    external: true