backend/mail: Allow different backends for mail

8 files changed, 115 insertions, 38 deletions

diff --git a/accounts/__init__.py b/accounts/__init__.py
index 8fbcdd0..09aa875 100644
--- a/accounts/__init__.py
+++ b/accounts/__init__.py
@@ -18,6 +18,7 @@ if 'SPLINE_ACCOUNT_WEB_SETTINGS' in os.environ:
 
 app.all_services = account.SERVICES #TODO: take that from our json file or so
 app.username_blacklist = list()
+app.mail_backend = get_backend(app.config['MAIL_BACKEND'], app)
 
 @app.before_request
 def session_permanent():
@@ -118,7 +119,7 @@ def register_complete(token):
         assert login_user(user.uid, user.password)
 
         if app.config.get('MAIL_REGISTER_NOTIFY'):
-            send_mail(
+            app.mail_backend.send(
                 app.config['MAIL_REGISTER_NOTIFY'],
                 u'[accounts] Neuer Benutzer %s erstellt' % username,
                 u'Benutzername: %s\nE-Mail:       %s\n\nSpammer? Deaktivieren: '
@@ -151,8 +152,9 @@ def lost_password():
         body = render_template('mail/lost_password.txt', username=form.user.uid,
                                link=confirm_link)
 
-        send_mail(form.user.attributes['mail'], u'Passwort vergessen', body,
-                  sender=app.config.get('MAIL_CONFIRM_SENDER'))
+        app.mail_backend.send(
+            form.user.attributes['mail'], u'Passwort vergessen', body,
+            sender=app.config.get('MAIL_CONFIRM_SENDER'))
 
         flash(u'Wir haben dir eine E-Mail mit einem Link zum Passwort ändern '
               u'geschickt. Bitte folge den Anweisungen in der E-Mail.', 'success')
@@ -210,8 +212,9 @@ def settings():
                 body = render_template('mail/change_mail.txt', username=g.user.uid,
                                        mail=form.mail.data, link=confirm_link)
 
-                send_mail(form.mail.data, u'E-Mail-Adresse bestätigen', body,
-                          sender=app.config.get('MAIL_CONFIRM_SENDER'))
+                app.mail_backend.send(
+                    form.mail.data, u'E-Mail-Adresse bestätigen', body,
+                    sender=app.config.get('MAIL_CONFIRM_SENDER'))
 
                 flash(u'Es wurde eine E-Mail an die angegebene Adresse geschickt, '
                       u'um diese zu überprüfen. Bitte folge den Anweisungen in der '
diff --git a/accounts/backend/__init__.py b/accounts/backend/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/accounts/backend/__init__.py
diff --git a/accounts/backend/mail/__init__.py b/accounts/backend/mail/__init__.py
new file mode 100644
index 0000000..c22b037
--- /dev/null
+++ b/accounts/backend/mail/__init__.py
@@ -0,0 +1,9 @@
+# -*- coding: utf-8 -*-
+
+class Backend(object):
+
+    def __init__(self, app):
+        self.app = app
+
+    def send(self, recipient, subject, body, sender=None):
+        raise NotImplementedError()
diff --git a/accounts/backend/mail/dummy.py b/accounts/backend/mail/dummy.py
new file mode 100644
index 0000000..d62a66b
--- /dev/null
+++ b/accounts/backend/mail/dummy.py
@@ -0,0 +1,48 @@
+# -*- coding: utf-8 -*-
+from __future__ import absolute_import
+
+from . import Backend
+from accounts.utils import ensure_utf8
+
+
+FANCY_FORMAT = '''\
+,---------------------------------------------------------------------------
+| Subject: {subject}
+| To: {to}
+| From: {sender}
+|---------------------------------------------------------------------------
+| {body}
+`---------------------------------------------------------------------------'''
+
+
+PLAIN_FORMAT = '''Subject: {subject}
+To: {to}
+From: {sender}
+
+{body}'''
+
+
+class DummyBackend(Backend):
+
+    def __init__(self, app, plain=False, format=None):
+        super(DummyBackend, self).__init__(app)
+        self.plain = plain
+
+        if format is None:
+            if self.plain:
+                self.format = PLAIN_FORMAT
+            else:
+                self.format = FANCY_FORMAT
+        else:
+            self.format = format
+
+    def send(self, recipient, subject, body, sender=None):
+        if sender is None:
+            sender = self.app.config['MAIL_DEFAULT_SENDER']
+
+        if not self.plain:
+            body = "\n| ".join(body.split("\n"))
+
+        print(self.format.format(
+            subject=ensure_utf8(subject), to=ensure_utf8(recipient),
+            sender=ensure_utf8(sender), body=ensure_utf8(body)))
diff --git a/accounts/backend/mail/sendmail.py b/accounts/backend/mail/sendmail.py
new file mode 100644
index 0000000..92b354e
--- /dev/null
+++ b/accounts/backend/mail/sendmail.py
@@ -0,0 +1,35 @@
+# -*- coding: utf-8 -*-
+from __future__ import absolute_import
+
+import subprocess
+from email.mime.text import MIMEText
+from email.utils import parseaddr
+
+from . import Backend
+
+
+class SendmailBackend(Backend):
+
+    def send(self, recipient, subject, body, sender=None):
+        if sender is None:
+            sender = self.app.config['MAIL_DEFAULT_SENDER']
+
+        safe = lambda s: s.split('\n', 1)[0]
+
+        msg = MIMEText(body, _charset='utf-8')
+        msg['Subject'] = safe(subject)
+        msg['To'] = safe(recipient)
+        msg['From'] = safe(sender)
+
+        envelope = []
+        _, address = parseaddr(safe(sender))
+        if address != '':
+            envelope = ['-f', address]
+
+        p = subprocess.Popen([self.app.config['SENDMAIL_COMMAND']] +
+                             envelope + ['-t'], stdin=subprocess.PIPE)
+        p.stdin.write(msg.as_string())
+        p.stdin.close()
+
+        if p.wait() != 0:
+            raise RuntimeError('sendmail terminated with %d' % p.returncode)
diff --git a/accounts/default_settings.py b/accounts/default_settings.py
index b51cbb3..538a8ed 100644
--- a/accounts/default_settings.py
+++ b/accounts/default_settings.py
@@ -22,3 +22,5 @@ LDAP_ADMIN_USER = 'admin'
 LDAP_ADMIN_PASS = 'admin'
 
 PREFERRED_URL_SCHEME = 'https'
+
+MAIL_BACKEND = 'accounts.backend.mail.dummy'
diff --git a/accounts/utils.py b/accounts/utils.py
index 86991b3..87a2ba8 100644
--- a/accounts/utils.py
+++ b/accounts/utils.py
@@ -1,14 +1,12 @@
 # -*- coding: utf-8 -*-
 import hmac
+import importlib
 import ldap
 import pickle
 import re
 import struct
-import subprocess
 from base64 import urlsafe_b64encode, urlsafe_b64decode
 from Crypto.Cipher import AES
-from email.mime.text import MIMEText
-from email.utils import parseaddr
 from functools import wraps
 from flask import current_app, flash, g, redirect, render_template, request, session
 from flask import url_for as flask_url_for
@@ -20,7 +18,6 @@ from werkzeug.exceptions import Forbidden
 from wtforms.validators import Regexp, ValidationError
 
 
-
 _username_re = re.compile(r'^[a-zA-Z][a-zA-Z0-9-]{1,15}$')
 _username_exclude_re = re.compile(r'^(admin|root)')
 
@@ -194,31 +191,6 @@ def constant_time_compare(val1, val2):
     return result == 0
 
 
-def send_mail(recipient, subject, body, sender=None):
-    if sender is None:
-        sender = current_app.config['MAIL_DEFAULT_SENDER']
-
-    safe = lambda s: s.split('\n', 1)[0]
-
-    msg = MIMEText(body, _charset='utf-8')
-    msg['Subject'] = safe(subject)
-    msg['To'] = safe(recipient)
-    msg['From'] = safe(sender)
-
-    envelope = []
-    (name, address) = parseaddr(safe(sender))
-    if address != '':
-        envelope = ['-f', address]
-
-    p = subprocess.Popen([current_app.config['SENDMAIL_COMMAND']] + envelope + ['-t'],
-                         stdin=subprocess.PIPE)
-    p.stdin.write(msg.as_string())
-    p.stdin.close()
-
-    if p.wait() != 0:
-        raise RuntimeError('sendmail terminated with %d' % p.returncode)
-
-
 class Service(object):
     def __init__(self, id, name, url):
         self.id = id
@@ -243,8 +215,9 @@ def send_register_confirmation_mail(username, mail):
     body = render_template('mail/register.txt', username=username,
                            mail=mail, link=confirm_link)
 
-    send_mail(mail, u'E-Mail-Adresse bestätigen', body,
-              sender=current_app.config.get('MAIL_CONFIRM_SENDER'))
+    current_app.mail_backend.send(
+        mail, u'E-Mail-Adresse bestätigen', body,
+        sender=current_app.config.get('MAIL_CONFIRM_SENDER'))
 
 
 class NotRegexp(Regexp):
@@ -272,3 +245,10 @@ def url_for(endpoint, **values):
 # used when we encounter inconsistent data etc
 class ShouldNotHappen(RuntimeError):
     pass
+
+
+def get_backend(path, app):
+    module = path.rsplit(".", 1).pop()
+    class_name = '%sBackend' % module.title()
+    backend_class = getattr(importlib.import_module(path), class_name)
+    return backend_class(app)
diff --git a/accounts/views/admin/__init__.py b/accounts/views/admin/__init__.py
index 998bf8b..02a2da1 100644
--- a/accounts/views/admin/__init__.py
+++ b/accounts/views/admin/__init__.py
@@ -6,7 +6,7 @@ from flask import current_app, redirect, request, g, flash, url_for
 from uuid import uuid4
 from werkzeug.exceptions import Forbidden
 
-from accounts.utils import templated, send_register_confirmation_mail, send_mail
+from accounts.utils import templated, send_register_confirmation_mail
 from accounts.forms import AdminCreateAccountForm, AdminDisableAccountForm
 
 
@@ -78,7 +78,7 @@ def disable_account():
               u'gesetzt.' % mail, 'success')
 
         if current_app.config.get('MAIL_REGISTER_NOTIFY'):
-            send_mail(
+            current_app.mail_backend.send(
                 current_app.config['MAIL_REGISTER_NOTIFY'],
                 u'[accounts] Benutzer %s deaktiviert' % form.user.uid,
                 'Benutzername: %s\nE-Mail war:   %s\n\ndurch:        %s\n' % \