basic mailer implementation

atst/app.py

@@ -22,6 +22,7 @@ from atst.domain.authz import Authorization
 from atst.models.permissions import Permissions
 from atst.eda_client import MockEDAClient
 from atst.uploader import Uploader
+from atst.utils.mailer import make_mailer
 
 
 ENV = os.getenv("FLASK_ENV", "dev")
@@ -47,6 +48,7 @@ def make_app(config):
     register_filters(app)
     make_eda_client(app)
     make_upload_storage(app)
+    make_mailer(app)
 
     db.init_app(app)
     csrf.init_app(app)

atst/routes/dev.py

@@ -1,4 +1,12 @@
-from flask import Blueprint, request, session, redirect
+from flask import (
+    Blueprint,
+    request,
+    session,
+    redirect,
+    render_template,
+    url_for,
+    current_app as app,
+)
 
 from . import redirect_after_login_url
 from atst.domain.users import Users
@@ -65,3 +73,17 @@ def login_dev():
     session["user_id"] = user.id
 
     return redirect(redirect_after_login_url())
+
+
+@bp.route("/test-email")
+def test_email():
+    app.mailer.send(
+        [request.args.get("to")], request.args.get("subject"), request.args.get("body")
+    )
+
+    return redirect(url_for("dev.messages"))
+
+
+@bp.route("/messages")
+def messages():
+    return render_template("dev/emails.html", messages=app.mailer.messages)

atst/utils/mailer.py

@@ -0,0 +1,77 @@
+import smtplib
+from email.message import EmailMessage
+from collections import deque
+
+
+class _HostConnection:
+    def __init__(self, server, port, username, password, use_tls=False):
+        self.server = server
+        self.port = port
+        self.username = username
+        self.password = password
+        self.use_tls = use_tls
+        self.host = None
+
+    def __enter__(self):
+        self.host = smtplib.SMTP_SSL(self.server, self.port)
+        if self.use_tls:
+            self.host.starttls()
+        self.host.login(self.username, self.password)
+
+        return self.host
+
+    def __exit__(self, *args):
+        if self.host:
+            self.host.quit()
+
+
+class Mailer:
+    def __init__(
+        self, server, port, sender, username, password, use_tls=False, debug=False
+    ):
+        self.server = server
+        self.port = port
+        self.sender = sender
+        self.username = username
+        self.password = password
+        self.use_tls = use_tls
+        self.debug = debug
+        self.messages = deque(maxlen=50)
+
+    def connection(self):
+        return _HostConnection(self.server, self.port, self.username, self.password)
+
+    def _message(self, recipients, subject, body):
+        msg = EmailMessage()
+        msg.set_content(body)
+        msg["From"] = self.sender
+        msg["To"] = ", ".join(recipients)
+        msg["Subject"] = subject
+
+        return msg
+
+    def send(self, recipients, subject, body):
+        message = self._message(recipients, subject, body)
+        if self.debug:
+            self.messages.appendleft(message)
+        else:
+            with self.connection() as conn:
+                conn.send_message(message)
+
+
+def _map_config(config):
+    return {
+        "server": config.get("MAIL_SERVER"),
+        "port": config.get("MAIL_PORT"),
+        "sender": config.get("MAIL_SENDER"),
+        "username": config.get("MAIL_USERNAME"),
+        "password": config.get("MAIL_PASSWORD"),
+        "use_tls": config.get("MAIL_TLS", False),
+        "debug": config.get("DEBUG", False),
+    }
+
+
+def make_mailer(app):
+    config = _map_config(app.config)
+    mailer = Mailer(**config)
+    app.mailer = mailer

templates/dev/emails.html

@@ -0,0 +1,6 @@
+{% for msg in messages %}
+  <div style="white-space: pre-wrap">
+{{ msg }}
+  </div>
+  <hr>
+{% endfor %}