Repository: scrapy/scrapy

Issue:
Accept single values for "to" and "cc" arguments when sending mails
Follow up to https://github.com/scrapy/scrapy/pull/2271#issuecomment-248341246

> What about checking for strings and raising an error?
> Passing a string is an easy mistake to make.
> Or maybe we can support passing a single string.

Discussion:

Patch:
diff --git a/docs/topics/email.rst b/docs/topics/email.rst
index 18d2f8084..aac93a91a 100644
--- a/docs/topics/email.rst
+++ b/docs/topics/email.rst
@@ -35,12 +35,6 @@ And here is how to use it to send an e-mail (without attachments)::
 
     mailer.send(to=["someone@example.com"], subject="Some subject", body="Some body", cc=["another@example.com"])
 
-.. note::
-    As shown in the example above, ``to`` and ``cc`` need to be lists
-    of email addresses, not single addresses, and even for one recipient,
-    i.e. ``to="someone@example.com"`` will not work.
-
-
 MailSender class reference
 ==========================
 
@@ -87,13 +81,13 @@ uses `Twisted non-blocking IO`_, like the rest of the framework.
         Send email to the given recipients.
 
         :param to: the e-mail recipients
-        :type to: list
+        :type to: str or list of str
 
         :param subject: the subject of the e-mail
         :type subject: str
 
         :param cc: the e-mails to CC
-        :type cc: list
+        :type cc: str or list of str
 
         :param body: the e-mail body
         :type body: str
diff --git a/scrapy/mail.py b/scrapy/mail.py
index c6339f25b..0bb395521 100644
--- a/scrapy/mail.py
+++ b/scrapy/mail.py
@@ -21,6 +21,8 @@ else:
 
 from twisted.internet import defer, reactor, ssl
 
+from .utils.misc import arg_to_iter
+
 logger = logging.getLogger(__name__)
 
 
@@ -48,6 +50,10 @@ class MailSender(object):
             msg = MIMEMultipart()
         else:
             msg = MIMENonMultipart(*mimetype.split('/', 1))
+
+        to = list(arg_to_iter(to))
+        cc = list(arg_to_iter(cc))
+
         msg['From'] = self.mailfrom
         msg['To'] = COMMASPACE.join(to)
         msg['Date'] = formatdate(localtime=True)


Test patch:
diff --git a/tests/test_mail.py b/tests/test_mail.py
index bd7e49621..b139e98d8 100644
--- a/tests/test_mail.py
+++ b/tests/test_mail.py
@@ -10,7 +10,8 @@ class MailSenderTest(unittest.TestCase):
 
     def test_send(self):
         mailsender = MailSender(debug=True)
-        mailsender.send(to=['test@scrapy.org'], subject='subject', body='body', _callback=self._catch_mail_sent)
+        mailsender.send(to=['test@scrapy.org'], subject='subject', body='body',
+                        _callback=self._catch_mail_sent)
 
         assert self.catched_msg
 
@@ -24,9 +25,16 @@ class MailSenderTest(unittest.TestCase):
         self.assertEqual(msg.get_payload(), 'body')
         self.assertEqual(msg.get('Content-Type'), 'text/plain')
 
+    def test_send_single_values_to_and_cc(self):
+        mailsender = MailSender(debug=True)
+        mailsender.send(to='test@scrapy.org', subject='subject', body='body',
+                        cc='test@scrapy.org', _callback=self._catch_mail_sent)
+
     def test_send_html(self):
         mailsender = MailSender(debug=True)
-        mailsender.send(to=['test@scrapy.org'], subject='subject', body='<p>body</p>', mimetype='text/html', _callback=self._catch_mail_sent)
+        mailsender.send(to=['test@scrapy.org'], subject='subject',
+                        body='<p>body</p>', mimetype='text/html',
+                        _callback=self._catch_mail_sent)
 
         msg = self.catched_msg['msg']
         self.assertEqual(msg.get_payload(), '<p>body</p>')
@@ -90,7 +98,8 @@ class MailSenderTest(unittest.TestCase):
 
         mailsender = MailSender(debug=True)
         mailsender.send(to=['test@scrapy.org'], subject=subject, body=body,
-                        attachs=attachs, charset='utf-8', _callback=self._catch_mail_sent)
+                        attachs=attachs, charset='utf-8',
+                        _callback=self._catch_mail_sent)
 
         assert self.catched_msg
         self.assertEqual(self.catched_msg['subject'], subject)
@@ -99,7 +108,8 @@ class MailSenderTest(unittest.TestCase):
         msg = self.catched_msg['msg']
         self.assertEqual(msg['subject'], subject)
         self.assertEqual(msg.get_charset(), Charset('utf-8'))
-        self.assertEqual(msg.get('Content-Type'), 'multipart/mixed; charset="utf-8"')
+        self.assertEqual(msg.get('Content-Type'),
+                         'multipart/mixed; charset="utf-8"')
 
         payload = msg.get_payload()
         assert isinstance(payload, list)