make sure a contact with website_email=reverse alias of another contact can't be created

app/dashboard/views/alias_contact_manager.py

@@ -220,7 +220,12 @@ def alias_contact_manager(alias_id):
                     reply_email=generate_reply_email(contact_email, current_user),
                 )
 
-                LOG.d("create reverse-alias for %s", contact_addr)
+                LOG.d(
+                    "create reverse-alias for %s %s, reverse alias:%s",
+                    contact_addr,
+                    alias,
+                    contact.reply_email,
+                )
                 Session.commit()
                 flash(f"Reverse alias for {contact_addr} is created", "success")
 

app/errors.py

@@ -14,3 +14,9 @@ class SubdomainInTrashError(Exception):
     """raised when a subdomain is deleted before """
 
     pass
+
+
+class CannotCreateContactForReverseAlias(Exception):
+    """raised when a contact is created that has website_email=reverse_alias of another contact"""
+
+    pass

app/models.py

@@ -35,7 +35,12 @@ from app.config import (
     MAX_NB_DIRECTORY,
 )
 from app.db import Session
-from app.errors import AliasInTrashError, DirectoryInTrashError, SubdomainInTrashError
+from app.errors import (
+    AliasInTrashError,
+    DirectoryInTrashError,
+    SubdomainInTrashError,
+    CannotCreateContactForReverseAlias,
+)
 from app.log import LOG
 from app.oauth_models import Scope
 from app.pw_models import PasswordOracle
@@ -109,7 +114,7 @@ class ModelMixin(object):
 
     @classmethod
     def create(cls, **kw):
-        # whether should call Session.commit
+        # whether to call Session.commit
         commit = kw.pop("commit", False)
         flush = kw.pop("flush", False)
 
@@ -1264,8 +1269,9 @@ class Alias(Base, ModelMixin):
     @classmethod
     def create(cls, **kw):
         commit = kw.pop("commit", False)
+        flush = kw.pop("flush", False)
 
-        r = cls(**kw)
+        new_alias = cls(**kw)
 
         email = kw["email"]
         # make sure email is lowercase and doesn't have any whitespace
@@ -1282,12 +1288,17 @@ class Alias(Base, ModelMixin):
         if "custom_domain_id" not in kw:
             custom_domain = Alias.get_custom_domain(email)
             if custom_domain:
-                r.custom_domain_id = custom_domain.id
+                new_alias.custom_domain_id = custom_domain.id
+
+        Session.add(new_alias)
 
-        Session.add(r)
         if commit:
             Session.commit()
-        return r
+
+        if flush:
+            Session.flush()
+
+        return new_alias
 
     @classmethod
     def create_new(cls, user, prefix, note=None, mailbox_id=None):
@@ -1534,6 +1545,31 @@ class Contact(Base, ModelMixin):
     def email(self):
         return self.website_email
 
+    @classmethod
+    def create(cls, **kw):
+        commit = kw.pop("commit", False)
+        flush = kw.pop("flush", False)
+
+        new_contact = cls(**kw)
+
+        website_email = kw["website_email"]
+        # make sure email is lowercase and doesn't have any whitespace
+        website_email = sanitize_email(website_email)
+
+        # make sure alias is not in global trash, i.e. DeletedAlias table
+        if Contact.get_by(reply_email=website_email):
+            raise CannotCreateContactForReverseAlias
+
+        Session.add(new_contact)
+
+        if commit:
+            Session.commit()
+
+        if flush:
+            Session.flush()
+
+        return new_contact
+
     def website_send_to(self):
         """return the email address with name.
         to use when user wants to send an email from the alias

email_handler.py

@@ -204,11 +204,6 @@ def get_or_create_contact(from_header: str, mail_from: str, alias: Alias) -> Con
             contact.mail_from = mail_from
             Session.commit()
     else:
-        LOG.d(
-            "create contact %s for alias %s",
-            contact_email,
-            alias,
-        )
 
         try:
             contact = Contact.create(
@@ -225,6 +220,13 @@ def get_or_create_contact(from_header: str, mail_from: str, alias: Alias) -> Con
                 LOG.d("Create a contact with invalid email for %s", alias)
                 contact.invalid_email = True
 
+            LOG.d(
+                "create contact %s for %s, reverse alias:%s",
+                contact_email,
+                alias,
+                contact.reply_email,
+            )
+
             Session.commit()
         except IntegrityError:
             LOG.w("Contact %s %s already exist", alias, contact_email)