Un-hardcode message ID in test backend, and add console backend

anymail/backends/console.py

@@ -0,0 +1,43 @@
+import uuid
+from django.core.mail.backends.console import EmailBackend as DjangoConsoleBackend
+
+from ..exceptions import AnymailError
+from .test import EmailBackend as AnymailTestBackend
+
+
+class EmailBackend(AnymailTestBackend, DjangoConsoleBackend):
+    """
+    Anymail backend that prints messages to the console, while retaining
+    anymail statuses and signals.
+    """
+
+    esp_name = "Console"
+
+    def get_esp_message_id(self, message):
+        # Generate a guaranteed-unique ID for the message
+        return str(uuid.uuid4())
+
+    def send_messages(self, email_messages):
+        if not email_messages:
+            return
+        msg_count = 0
+        with self._lock:
+            try:
+                stream_created = self.open()
+                for message in email_messages:
+                    try:
+                        sent = self._send(message)
+                    except AnymailError:
+                        if self.fail_silently:
+                            sent = False
+                        else:
+                            raise
+                    if sent:
+                        self.write_message(message)
+                        self.stream.flush()  # flush after each message
+                        msg_count += 1
+            finally:
+                if stream_created:
+                    self.close()
+
+        return msg_count

anymail/backends/test.py

@@ -27,6 +27,11 @@ def __init__(self, *args, **kwargs):
         if not hasattr(mail, 'outbox'):
             mail.outbox = []  # see django.core.mail.backends.locmem
 
+    def get_esp_message_id(self, message):
+        # Get a unique ID for the message.  The message must have been added to
+        # the outbox first.
+        return mail.outbox.index(message)
+
     def build_message_payload(self, message, defaults):
         return TestPayload(backend=self, message=message, defaults=defaults)
 
@@ -41,7 +46,10 @@ def post_to_esp(self, payload, message):
                 raise response
         except AttributeError:
             # Default is to return 'sent' for each recipient
-            status = AnymailRecipientStatus(message_id=1, status='sent')
+            status = AnymailRecipientStatus(
+                message_id=self.get_esp_message_id(message),
+                status='sent'
+            )
             response = {
                 'recipient_status': {email: status for email in payload.recipient_emails}
             }

tests/test_send_signals.py

@@ -65,9 +65,9 @@ def handle_post_send(sender, message, status, esp_name, **kwargs):
             self.assertEqual(sender, TestEmailBackend)
             self.assertEqual(message, self.message)
             self.assertEqual(status.status, {'sent'})
-            self.assertEqual(status.message_id, 1)  # TestEmailBackend default message_id
+            self.assertEqual(status.message_id, 0)
             self.assertEqual(status.recipients['to@example.com'].status, 'sent')
-            self.assertEqual(status.recipients['to@example.com'].message_id, 1)
+            self.assertEqual(status.recipients['to@example.com'].message_id, 0)
             self.assertEqual(esp_name, "Test")  # the TestEmailBackend's ESP is named "Test"
             self.receiver_called = True
         self.addCleanup(post_send.disconnect, receiver=handle_post_send)