Refactored email code to use python-rq and the (new) send_async_email function

Author: sandlerben

app/account/views.py

@@ -7,7 +7,7 @@
 )
 from . import account
 from .. import db
-from ..email import send_email
+from ..email import send_async_email
 from ..models import User
 from .forms import (
     LoginForm,
@@ -18,6 +18,7 @@
     RequestResetPasswordForm,
     ResetPasswordForm
 )
+from app import redis_queue
 
 
 @account.route('/login', methods=['GET', 'POST'])
@@ -26,7 +27,8 @@ def login():
     form = LoginForm()
     if form.validate_on_submit():
         user = User.query.filter_by(email=form.email.data).first()
-        if user is not None and user.verify_password(form.password.data):
+        if user is not None and user.password_hash is not None and \
+                user.verify_password(form.password.data):
             login_user(user, form.remember_me.data)
             flash('You are now logged in. Welcome back!', 'success')
             return redirect(request.args.get('next') or url_for('main.index'))
@@ -47,8 +49,15 @@ def register():
         db.session.add(user)
         db.session.commit()
         token = user.generate_confirmation_token()
-        send_email(user.email, 'Confirm Your Account',
-                   'account/email/confirm', user=user, token=token)
+        confirm_link = url_for('account.confirm', token=token, _external=True)
+        redis_queue.enqueue(
+            send_async_email,
+            recipient=user.email,
+            subject='Confirm Your Account',
+            template='account/email/confirm',
+            user=user,
+            confirm_link=confirm_link
+        )
         flash('A confirmation link has been sent to {}.'.format(user.email),
               'warning')
         return redirect(url_for('main.index'))
@@ -81,12 +90,17 @@ def reset_password_request():
         user = User.query.filter_by(email=form.email.data).first()
         if user:
             token = user.generate_password_reset_token()
-            send_email(user.email,
-                       'Reset Your Password',
-                       'account/email/reset_password',
-                       user=user,
-                       token=token,
-                       next=request.args.get('next'))
+            reset_link = url_for('account.reset_password', token=token,
+                                 _external=True)
+            redis_queue.enqueue(
+                send_async_email,
+                recipient=user.email,
+                subject='Reset Your Password',
+                template='account/email/reset_password',
+                user=user,
+                reset_link=reset_link,
+                next=request.args.get('next')
+            )
         flash('A password reset link has been sent to {}.'
               .format(form.email.data),
               'warning')
@@ -141,11 +155,18 @@ def change_email_request():
         if current_user.verify_password(form.password.data):
             new_email = form.email.data
             token = current_user.generate_email_change_token(new_email)
-            send_email(new_email,
-                       'Confirm Your New Email',
-                       'account/email/change_email',
-                       user=current_user,
-                       token=token)
+            change_email_link = url_for('account.change_email', token=token,
+                                        _external=True)
+            redis_queue.enqueue(
+                send_async_email,
+                recipient=new_email,
+                subject='Confirm Your New Email',
+                template='account/email/change_email',
+                # current_user is a LocalProxy, we want the underlying user
+                # object
+                user=current_user._get_current_object(),
+                change_email_link=change_email_link
+            )
             flash('A confirmation link has been sent to {}.'.format(new_email),
                   'warning')
             return redirect(url_for('main.index'))
@@ -170,8 +191,16 @@ def change_email(token):
 def confirm_request():
     """Respond to new user's request to confirm their account."""
     token = current_user.generate_confirmation_token()
-    send_email(current_user.email, 'Confirm Your Account',
-               'account/email/confirm', user=current_user, token=token)
+    confirm_link = url_for('account.confirm', token=token, _external=True)
+    redis_queue.enqueue(
+        send_async_email,
+        recipient=current_user.email,
+        subject='Confirm Your Account',
+        template='account/email/confirm',
+        # current_user is a LocalProxy, we want the underlying user object
+        user=current_user._get_current_object(),
+        confirm_link=confirm_link
+    )
     flash('A new confirmation link has been sent to {}.'.
           format(current_user.email),
           'warning')
@@ -225,12 +254,16 @@ def join_from_invite(user_id, token):
         flash('The confirmation link is invalid or has expired. Another '
               'invite email with a new link has been sent to you.', 'error')
         token = new_user.generate_confirmation_token()
-        send_email(new_user.email,
-                   'You Are Invited To Join',
-                   'account/email/invite',
-                   user=new_user,
-                   user_id=new_user.id,
-                   token=token)
+        invite_link = url_for('account.join_from_invite', user_id=user_id,
+                              token=token, _external=True)
+        redis_queue.enqueue(
+            send_async_email,
+            recipient=new_user.email,
+            subject='You Are Invited To Join',
+            template='account/email/invite',
+            user=new_user,
+            invite_link=invite_link
+        )
     return redirect(url_for('main.index'))
 
 

app/admin/views.py

@@ -12,7 +12,8 @@
 from . import admin
 from ..models import User, Role
 from .. import db
-from ..email import send_email
+from ..email import send_async_email
+from app import redis_queue
 
 
 @admin.route('/')
@@ -56,12 +57,16 @@ def invite_user():
         db.session.add(user)
         db.session.commit()
         token = user.generate_confirmation_token()
-        send_email(user.email,
-                   'You Are Invited To Join',
-                   'account/email/invite',
-                   user=user,
-                   user_id=user.id,
-                   token=token)
+        invite_link = url_for('account.join_from_invite', user_id=user.id,
+                              token=token, _external=True)
+        redis_queue.enqueue(
+            send_async_email,
+            recipient=user.email,
+            subject='You Are Invited To Join',
+            template='account/email/invite',
+            user=user,
+            invite_link=invite_link,
+        )
         flash('User {} successfully invited'.format(user.full_name()),
               'form-success')
     return render_template('admin/new_user.html', form=form)

app/email.py

@@ -1,21 +1,16 @@
-from threading import Thread
-
-from flask import current_app, render_template
+import os
+from flask import render_template
 from flask.ext.mail import Message
 from . import mail
+from app import create_app
 
 
-def send_async_email(app, msg):
+def send_async_email(recipient, subject, template, **kwargs):
+    app = create_app(os.getenv('FLASK_CONFIG') or 'default')
     with app.app_context():
+        msg = Message(app.config['EMAIL_SUBJECT_PREFIX'] + ' ' + subject,
+                      sender=app.config['EMAIL_SENDER'],
+                      recipients=[recipient])
+        msg.body = render_template(template + '.txt', **kwargs)
+        msg.html = render_template(template + '.html', **kwargs)
         mail.send(msg)
-
-
-def send_email(to, subject, template, **kwargs):
-    app = current_app._get_current_object()
-    msg = Message(app.config['EMAIL_SUBJECT_PREFIX'] + ' ' + subject,
-                  sender=app.config['EMAIL_SENDER'], recipients=[to])
-    msg.body = render_template(template + '.txt', **kwargs)
-    msg.html = render_template(template + '.html', **kwargs)
-    thr = Thread(target=send_async_email, args=[app, msg])
-    thr.start()
-    return thr

app/templates/account/email/change_email.html

@@ -1,10 +1,10 @@
 <p>Dear {{ user.full_name() }},</p>
 
-<p>To confirm your new email address <a href="{{ url_for('account.change_email', token=token, _external=True) }}">click here</a>.</p>
+<p>To confirm your new email address <a href="{{ change_email_link }}">click here</a>.</p>
 
 <p>Alternatively, you can paste the following link in your browser's address bar:</p>
 
-<p>{{ url_for('account.change_email', token=token, _external=True) }}</p>
+<p>{{ change_email_link }}</p>
 
 <p>Sincerely,</p>
 

app/templates/account/email/change_email.txt

@@ -2,7 +2,7 @@ Dear {{ user.full_name() }},
 
 To confirm your new email address click on the following link:
 
-{{ url_for('account.change_email', token=token, _external=True) }}
+{{ change_email_link }}
 
 Sincerely,
 

app/templates/account/email/confirm.html

@@ -2,11 +2,11 @@
 
 <p>Welcome to <b>{{ config.APP_NAME }}</b>!</p>
 
-<p>To confirm your account, please <a href="{{ url_for('account.confirm', token=token, _external=True) }}">click here</a>.</p>
+<p>To confirm your account, please <a href="{{ confirm_link }}">click here</a>.</p>
 
 <p>Alternatively, you can paste the following link in your browser's address bar:</p>
 
-<p>{{ url_for('account.confirm', token=token, _external=True) }}</p>
+<p>{{ confirm_link }}</p>
 
 <p>Sincerely,</p>
 

app/templates/account/email/confirm.txt

@@ -4,7 +4,7 @@ Welcome to {{ config.APP_NAME }}!
 
 To confirm your account, please click on the following link:
 
-{{ url_for('account.confirm', token=token, _external=True) }}
+{{ confirm_link }}
 
 Sincerely,
 

app/templates/account/email/invite.html

@@ -2,11 +2,11 @@
 
 <p>You are invited to join <b>{{ config.APP_NAME }}</b>!</p>
 
-<p>To set your password, please <a href="{{ url_for('account.join_from_invite', user_id=user_id, token=token, _external=True) }}">click here</a>.</p>
+<p>To set your password, please <a href="{{ invite_link }}">click here</a>.</p>
 
 <p>Alternatively, you can paste the following link in your browser's address bar:</p>
 
-<p>{{ url_for('account.join_from_invite', user_id=user_id, token=token, _external=True) }}</p>
+<p>{{ invite_link }}</p>
 
 <p>Once completed, please log in as {{ user.email }} with the password you set.</p>
 

app/templates/account/email/invite.txt

@@ -4,7 +4,7 @@ You are invited to join {{ config.APP_NAME }}!
 
 To set your password, please click on the following link:
 
-{{ url_for('account.join_from_invite', user_id=user_id, token=token, _external=True) }}
+{{ invite_link }}
 
 Once completed, please log in as {{ user.email }} with the password you set.
 

app/templates/account/email/reset_password.html

@@ -1,10 +1,10 @@
 <p>Dear {{ user.full_name() }},</p>
 
-<p>To reset your password, <a href="{{ url_for('account.reset_password', token=token, _external=True) }}">click here</a>.</p>
+<p>To reset your password, <a href="{{ reset_link }}">click here</a>.</p>
 
 <p>Alternatively, you can paste the following link in your browser's address bar:</p>
 
-<p>{{ url_for('account.reset_password', token=token, _external=True) }}</p>
+<p>{{ reset_link }}</p>
 
 <p>If you have not requested a password reset, simply ignore this message.</p>