Merge pull request #384 from dod-ccpo/mailer

Mailer

atst/app.py

@@ -23,6 +23,8 @@ 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 import mailer
+from atst.queue import queue
 
 
 ENV = os.getenv("FLASK_ENV", "dev")
@@ -37,17 +39,19 @@ def make_app(config):
         template_folder=parent_dir.child("templates").absolute(),
         static_folder=parent_dir.child("static").absolute(),
     )
-    redis = make_redis(config)
+    make_redis(app, config)
     csrf = CSRFProtect()
 
     app.config.update(config)
-    app.config.update({"SESSION_REDIS": redis})
+    app.config.update({"SESSION_REDIS": app.redis})
 
     make_flask_callbacks(app)
     make_crl_validator(app)
     register_filters(app)
     make_eda_client(app)
     make_upload_storage(app)
+    make_mailer(app)
+    queue.init_app(app)
 
     db.init_app(app)
     csrf.init_app(app)
@@ -87,7 +91,7 @@ def map_config(config):
     return {
         **config["default"],
         "ENV": config["default"]["ENVIRONMENT"],
-        "DEBUG": config["default"]["DEBUG"],
+        "DEBUG": config["default"].getboolean("DEBUG"),
         "PORT": int(config["default"]["PORT"]),
         "SQLALCHEMY_DATABASE_URI": config["default"]["DATABASE_URI"],
         "SQLALCHEMY_TRACK_MODIFICATIONS": False,
@@ -95,6 +99,8 @@ def map_config(config):
         "PERMANENT_SESSION_LIFETIME": config.getint(
             "default", "PERMANENT_SESSION_LIFETIME"
         ),
+        "RQ_REDIS_URL": config["default"]["REDIS_URI"],
+        "RQ_QUEUES": ["atat_{}".format(ENV.lower())],
     }
 
 
@@ -143,8 +149,9 @@ def make_config():
     return map_config(config)
 
 
-def make_redis(config):
-    return redis.Redis.from_url(config["REDIS_URI"])
+def make_redis(app, config):
+    r = redis.Redis.from_url(config["REDIS_URI"])
+    app.redis = r
 
 
 def make_crl_validator(app):
@@ -166,3 +173,18 @@ def make_upload_storage(app):
         secret=app.config.get("STORAGE_SECRET"),
     )
     app.uploader = uploader
+
+
+def make_mailer(app):
+    if app.config["DEBUG"]:
+        mailer_connection = mailer.RedisConnection(app.redis)
+    else:
+        mailer_connection = mailer.SMTPConnection(
+            server=app.config.get("MAIL_SERVER"),
+            port=app.config.get("MAIL_PORT"),
+            username=app.config.get("MAIL_SENDER"),
+            password=app.config.get("MAIL_PASSWORD"),
+            use_tls=app.config.get("MAIL_TLS"),
+        )
+    sender = app.config.get("MAIL_SENDER")
+    app.mailer = mailer.Mailer(mailer_connection, sender)

atst/queue.py

@@ -0,0 +1,45 @@
+from flask_rq2 import RQ
+from flask import current_app as app
+
+
+class ATSTQueue(RQ):
+
+    """Internal helpers to get the queue that actually does the work.
+
+    The RQ object always uses the "default" queue, unless we explicitly request
+    otherwise. These helpers allow us to use `.queue_name` to get the name of
+    the configured queue and `_queue_job` will use the appropriate queue.
+
+    """
+
+    @property
+    def queue_name(self):
+        return self.queues[0]
+
+    def get_queue(self, name=None):
+        if not name:
+            name = self.queue_name
+        return super().get_queue(name)
+
+    def _queue_job(self, function, *args, **kwargs):
+        self.get_queue().enqueue(function, *args, **kwargs)
+
+    # pylint: disable=pointless-string-statement
+    """Instance methods to queue up application-specific jobs."""
+
+    def send_mail(self, to, subject, body):
+        self._queue_job(ATSTQueue._send_mail, to, subject, body)
+
+    # pylint: disable=pointless-string-statement
+    """Class methods to actually perform the work.
+
+    Must be a class method (or a module-level function) because we being able
+    to pickle the class is more effort than its worth.
+    """
+
+    @classmethod
+    def _send_mail(self, to, subject, body):
+        app.mailer.send(to, subject, body)
+
+
+queue = ATSTQueue()

atst/routes/dev.py

@@ -1,7 +1,16 @@
-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
+from atst.queue import queue
 
 bp = Blueprint("dev", __name__)
 
@@ -65,3 +74,17 @@ def login_dev():
     session["user_id"] = user.id
 
     return redirect(redirect_after_login_url())
+
+
+@bp.route("/test-email")
+def test_email():
+    queue.send_mail(
+        [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 +1,85 @@
+from contextlib import contextmanager
+import smtplib
+from email.message import EmailMessage
+
+
+class MailConnection(object):
+    def send(self, message):
+        raise NotImplementedError()
+
+    @property
+    def messages(self):
+        raise NotImplementedError()
+
+
+class SMTPConnection(MailConnection):
+    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
+
+    @contextmanager
+    def _connected_host(self):
+        host = None
+
+        if self.use_tls:
+            host = smtplib.SMTP(self.server, self.port)
+            host.starttls()
+        else:
+            host = smtplib.SMTP_SSL(self.server, self.port)
+
+        host.login(self.username, self.password)
+
+        yield host
+
+        host.quit()
+
+    @property
+    def messages(self):
+        return []
+
+    def send(self, message):
+        with self._connected_host() as host:
+            host.send_message(message)
+
+
+class RedisConnection(MailConnection):
+    def __init__(self, redis, **kwargs):
+        super().__init__(**kwargs)
+        self.redis = redis
+        self._reset()
+
+    def _reset(self):
+        self.redis.delete("atat_inbox")
+
+    @property
+    def messages(self):
+        return [msg.decode() for msg in self.redis.lrange("atat_inbox", 0, -1)]
+
+    def send(self, message):
+        self.redis.lpush("atat_inbox", str(message))
+
+
+class Mailer(object):
+    def __init__(self, connection, sender):
+        self.connection = connection
+        self.sender = sender
+
+    def _build_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._build_message(recipients, subject, body)
+        self.connection.send(message)
+
+    @property
+    def messages(self):
+        return self.connection.messages