--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/backend/tools/common/email.py	Fri Jun 02 11:49:51 2023 +0200
@@ -0,0 +1,84 @@
+#!/usr/bin/env python3
+
+
+# SàT: a jabber client
+# Copyright (C) 2009-2021 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""email sending facilities"""
+
+
+from email.mime.text import MIMEText
+from twisted.mail import smtp
+from libervia.backend.core.constants import Const as C
+from libervia.backend.tools import config as tools_config
+from libervia.backend.core.log import getLogger
+
+log = getLogger(__name__)
+
+
+def send_email(config, to_emails, subject="", body="", from_email=None):
+    """Send an email using SàT configuration
+
+    @param config (SafeConfigParser): the configuration instance
+    @param to_emails(list[unicode], unicode): list of recipients
+        if unicode, it will be split to get emails
+    @param subject(unicode): subject of the message
+    @param body(unicode): body of the message
+    @param from_email(unicode): address of the sender
+    @return (D): same as smtp.sendmail
+    """
+    if isinstance(to_emails, str):
+        to_emails = to_emails.split()
+    email_host = tools_config.config_get(config, None, "email_server") or "localhost"
+    email_from = from_email or tools_config.config_get(config, None, "email_from")
+
+    # we suppose that email domain and XMPP domain are identical
+    domain = tools_config.config_get(config, None, "xmpp_domain")
+    if domain is None:
+        if email_from is not None:
+            domain = email_from.split("@", 1)[-1]
+        else:
+            domain = "example.net"
+
+    if email_from is None:
+        email_from = "no_reply@" + domain
+    email_sender_domain = tools_config.config_get(
+        config, None, "email_sender_domain", domain
+    )
+    email_port = int(tools_config.config_get(config, None, "email_port", 25))
+    email_username = tools_config.config_get(config, None, "email_username")
+    email_password = tools_config.config_get(config, None, "email_password")
+    email_auth = C.bool(tools_config.config_get(config, None, "email_auth", C.BOOL_FALSE))
+    email_starttls = C.bool(tools_config.config_get(config, None, "email_starttls",
+                            C.BOOL_FALSE))
+
+    msg = MIMEText(body, "plain", "UTF-8")
+    msg["Subject"] = subject
+    msg["From"] = email_from
+    msg["To"] = ", ".join(to_emails)
+
+    return smtp.sendmail(
+        email_host.encode("utf-8"),
+        email_from.encode("utf-8"),
+        [email.encode("utf-8") for email in to_emails],
+        msg.as_bytes(),
+        senderDomainName=email_sender_domain if email_sender_domain else None,
+        port=email_port,
+        username=email_username.encode("utf-8") if email_username else None,
+        password=email_password.encode("utf-8") if email_password else None,
+        requireAuthentication=email_auth,
+        requireTransportSecurity=email_starttls,
+    )