From: Michael Tremer <michael.tremer@ipfire.org>
Date: Mon, 16 Feb 2026 19:28:15 +0000 (+0000)
Subject: exports: Add a canary domain to all exports
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=25c103a691a2c0b8f3b46b36b1bc49fba005d226;p=dbl.git

exports: Add a canary domain to all exports

This is so that we can identify when we are reading back our own data.

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/dbl/lists.py b/src/dbl/lists.py
index 9c3bf42..f910496 100644
--- a/src/dbl/lists.py
+++ b/src/dbl/lists.py
@@ -255,6 +255,21 @@ class List(sqlmodel.SQLModel, database.BackendMixin, table=True):
 		# Join it all together
 		return ".".join(e for e in s if e)
 
+	@functools.cached_property
+	def canary(self):
+		"""
+			Creates a canary that will be inserted into all exports
+			and will be checked if we import a source to avoid that we will
+			import our own data in a circle.
+		"""
+		# Make a unique canary
+		canary = "canary.%s" % self.zone(prefix="dbl")
+
+		# Remove the trailing dot
+		canary = canary.removesuffix(".")
+
+		return canary
+
 	@functools.cached_property
 	def __domains(self):
 		"""
@@ -340,14 +355,29 @@ class List(sqlmodel.SQLModel, database.BackendMixin, table=True):
 		"""
 			Returns all domains that are on this list
 		"""
-		stmt = (
+		domains = self.backend.db.fetch(
 			sqlmodel
 			.select(
 				self.__domains.c.name,
 			)
 		)
 
-		return self.backend.db.fetch(stmt)
+		canary_inserted = False
+
+		# Walk through all domains and insert the canary
+		for domain in domains:
+			# If we have not inserted the canary, yet, we will do
+			# it whenever it alphabetically fits
+			if not canary_inserted and domain > self.canary:
+				yield self.canary
+				canary_inserted = True
+
+			# Add the domain, too
+			yield domain
+
+		# If we have added all domains but not the canary, we will add the canary anyways
+		if not canary_inserted:
+			yield self.canary
 
 	def add_domain(self, name, added_by, report=None, block=True):
 		"""