From 602a320af846081ad8cd4f267f29eacdeb00fb30 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=86=AF=E5=9F=BA=E9=AD=81?= <1412414664@qq.com>
Date: Wed, 24 Jun 2026 17:50:06 +0800
Subject: [PATCH] fix: guard source resource lookup before init

---
 dlt/extract/source.py         | 11 ++++++++---
 tests/extract/test_sources.py | 10 ++++++++++
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/dlt/extract/source.py b/dlt/extract/source.py
index 48a1aa9f89..cc14caf3dd 100644
--- a/dlt/extract/source.py
+++ b/dlt/extract/source.py
@@ -611,7 +611,9 @@ def __iter__(self) -> Generator[TDataItem, None, None]:
             Container().injectable_context(source_context),
             Container().injectable_context(schema_context),
         ):
-            pipe_iterator: ManagedPipeIterator = ManagedPipeIterator.from_pipes(self._resources.selected_pipes)  # type: ignore
+            pipe_iterator: ManagedPipeIterator = ManagedPipeIterator.from_pipes(
+                self._resources.selected_pipes
+            )  # type: ignore
         pipe_iterator.set_context([section_context, state_context, schema_context, source_context])
         _iter = map(lambda item: item.item, pipe_iterator)
         return flatten_list_or_items(_iter)
@@ -629,10 +631,13 @@ def __getattr__(self, resource_name: str) -> DltResource:
         # do not intercept dunder attributes (needed for copy/pickle/deepcopy)
         if resource_name.startswith("__") and resource_name.endswith("__"):
             raise AttributeError(resource_name)
+        resources = self.__dict__.get("_resources")
+        if resources is None:
+            raise AttributeError(resource_name)
         try:
-            return self._resources[resource_name]
+            return resources[resource_name]
         except KeyError:
-            all_resources = ", ".join(self._resources.keys())
+            all_resources = ", ".join(resources.keys())
             raise AttributeError(
                 f"Resource `{resource_name}` not found in source `{self.name}`. Available"
                 f" resources: {all_resources}"
diff --git a/tests/extract/test_sources.py b/tests/extract/test_sources.py
index 3de084747b..36a5caa322 100644
--- a/tests/extract/test_sources.py
+++ b/tests/extract/test_sources.py
@@ -539,6 +539,16 @@ def test_source(no_resources):
     assert list(s.with_resources()) == []
 
 
+def test_source_getattr_without_resources_raises_attribute_error() -> None:
+    source = DltSource.__new__(DltSource)
+
+    with pytest.raises(AttributeError, match="anything"):
+        source.anything
+
+    with pytest.raises(AttributeError, match="_resources"):
+        source._resources
+
+
 def test_clone_source() -> None:
     @dlt.source
     def test_source(no_resources):