Add a button to test email settings in the Preferences dialog, should help with debugging email problems.

src/calibre/gui2/dialogs/config.py

@@ -1,6 +1,6 @@
 __license__   = 'GPL v3'
 __copyright__ = '2008, Kovid Goyal <kovid at kovidgoyal.net>'
-import os, re, time, textwrap
+import os, re, time, textwrap, sys, cStringIO
 from binascii import hexlify, unhexlify
 
 from PyQt4.Qt import    QDialog, QMessageBox, QListWidgetItem, QIcon, \
@@ -11,6 +11,7 @@ from PyQt4.Qt import    QDialog, QMessageBox, QListWidgetItem, QIcon, \
 
 from calibre.constants import islinux, iswindows
 from calibre.gui2.dialogs.config_ui import Ui_Dialog
+from calibre.gui2.dialogs.test_email_ui import Ui_Dialog as TE_Dialog
 from calibre.gui2 import qstring_to_unicode, choose_dir, error_dialog, config, \
                          ALL_COLUMNS, NONE, info_dialog, choose_files
 from calibre.utils.config import prefs
@@ -134,6 +135,33 @@ class CategoryModel(QStringListModel):
             return self.icons[index.row()]
         return QStringListModel.data(self, index, role)
 
+class TestEmail(QDialog, TE_Dialog):
+
+    def __init__(self, accounts, parent):
+        QDialog.__init__(self, parent)
+        TE_Dialog.__init__(self)
+        self.setupUi(self)
+        opts = smtp_prefs().parse()
+        self.test_func = parent.test_email_settings
+        self.connect(self.test_button, SIGNAL('clicked(bool)'), self.test)
+        self.from_.setText(unicode(self.from_.text())%opts.from_)
+        if accounts:
+            self.to.setText(list(accounts.keys())[0])
+        if opts.relay_host:
+            self.label.setText(_('Using: %s:%s@%s:%s and %s encryption')%
+                    (opts.relay_username, unhexlify(opts.relay_password),
+                        opts.relay_host, opts.relay_port, opts.encryption))
+
+    def test(self):
+        self.log.setPlainText(_('Sending...'))
+        self.test_button.setEnabled(False)
+        try:
+            tb = self.test_func(unicode(self.to.text()))
+            if not tb:
+                tb = _('Mail successfully sent')
+            self.log.setPlainText(tb)
+        finally:
+            self.test_button.setEnabled(True)
 
 class EmailAccounts(QAbstractTableModel):
 
@@ -395,6 +423,8 @@ class ConfigDialog(QDialog, Ui_Dialog):
         self.connect(self.email_make_default, SIGNAL('clicked(bool)'),
              lambda c: self._email_accounts.make_default(self.email_view.currentIndex()))
         self.email_view.resizeColumnsToContents()
+        self.connect(self.test_email_button, SIGNAL('clicked(bool)'),
+                self.test_email)
 
     def add_email_account(self, checked):
         index = self._email_accounts.add()
@@ -438,6 +468,33 @@ class ConfigDialog(QDialog, Ui_Dialog):
         conf.set('encryption', 'TLS' if self.relay_tls.isChecked() else 'SSL')
         return True
 
+    def test_email(self, *args):
+        if self.set_email_settings():
+          TestEmail(self._email_accounts.accounts, self).exec_()
+
+    def test_email_settings(self, to):
+        opts = smtp_prefs().parse()
+        from calibre.utils.smtp import sendmail, create_mail
+        buf = cStringIO.StringIO()
+        oout, oerr = sys.stdout, sys.stderr
+        sys.stdout = sys.stderr = buf
+        tb = None
+        try:
+            msg = create_mail(opts.from_, to, 'Test mail from calibre',
+                    'Test mail from calibre')
+            sendmail(msg, from_=opts.from_, to=[to],
+                verbose=3, timeout=30, relay=opts.relay_host,
+                username=opts.relay_username,
+                password=unhexlify(opts.relay_password),
+                encryption=opts.encryption, port=opts.relay_port)
+        except:
+            import traceback
+            tb = traceback.format_exc()
+            tb += '\n\nLog:\n' + buf.getvalue()
+        finally:
+            sys.stdout, sys.stderr = oout, oerr
+        return tb
+
     def add_plugin(self):
         path = unicode(self.plugin_path.text())
         if path and os.access(path, os.R_OK) and path.lower().endswith('.zip'):

src/calibre/gui2/dialogs/test_email.ui

@@ -0,0 +1,103 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>Dialog</class>
+ <widget class="QDialog" name="Dialog">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>542</width>
+    <height>418</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Test email settings</string>
+  </property>
+  <property name="windowIcon">
+   <iconset resource="../images.qrc">
+    <normaloff>:/images/config.svg</normaloff>:/images/config.svg</iconset>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <item>
+    <widget class="QLabel" name="from_">
+     <property name="text">
+      <string>Send test mail from %s to:</string>
+     </property>
+     <property name="wordWrap">
+      <bool>true</bool>
+     </property>
+    </widget>
+   </item>
+   <item>
+    <widget class="QLineEdit" name="to"/>
+   </item>
+   <item>
+    <widget class="QLabel" name="label">
+     <property name="text">
+      <string/>
+     </property>
+     <property name="wordWrap">
+      <bool>true</bool>
+     </property>
+    </widget>
+   </item>
+   <item>
+    <widget class="QPushButton" name="test_button">
+     <property name="text">
+      <string>&amp;Test</string>
+     </property>
+    </widget>
+   </item>
+   <item>
+    <widget class="QPlainTextEdit" name="log"/>
+   </item>
+   <item>
+    <widget class="QDialogButtonBox" name="buttonBox">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="standardButtons">
+      <set>QDialogButtonBox::Ok</set>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <resources>
+  <include location="../images.qrc"/>
+ </resources>
+ <connections>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>accepted()</signal>
+   <receiver>Dialog</receiver>
+   <slot>accept()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>248</x>
+     <y>254</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>157</x>
+     <y>274</y>
+    </hint>
+   </hints>
+  </connection>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>rejected()</signal>
+   <receiver>Dialog</receiver>
+   <slot>reject()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>316</x>
+     <y>260</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>286</x>
+     <y>274</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
+</ui>

src/calibre/utils/smtp.py

@@ -45,15 +45,17 @@ def create_mail(from_, to, subject, text=None, attachment_data=None,
 
     return outer.as_string()
 
-def get_mx(host):
+def get_mx(host, verbose=0):
     import dns.resolver
+    if verbose:
+        print 'Find mail exchanger for', host
     answers = list(dns.resolver.query(host, 'MX'))
     answers.sort(cmp=lambda x, y: cmp(int(x.preference), int(y.preference)))
     return [str(x.exchange) for x in answers]
 
 def sendmail_direct(from_, to, msg, timeout, localhost, verbose):
     import smtplib
-    hosts = get_mx(to.split('@')[-1].strip())
+    hosts = get_mx(to.split('@')[-1].strip(), verbose)
     timeout=None # Non blocking sockets sometimes don't work
     s = smtplib.SMTP(timeout=timeout, local_hostname=localhost)
     s.set_debuglevel(verbose)