gh-148849: Deprecate http.cookies.BaseCookie.js_output() (GH-148978)

Author: kishorhange111

Doc/deprecations/pending-removal-in-3.19.rst

@@ -22,3 +22,12 @@ Pending removal in Python 3.19
     supported depending on the backend implementation of hash functions.
     Prefer passing the initial data as a positional argument for maximum
     backwards compatibility.
+
+* :mod:`http.cookies`:
+
+  * :meth:`http.cookies.Morsel.js_output` is deprecated and will be
+    removed in Python 3.19.
+
+  * :meth:`http.cookies.BaseCookie.js_output` is deprecated and will be
+    removed in Python 3.19.
+

Doc/library/http.cookies.rst

@@ -107,6 +107,12 @@ Cookie Objects
 
    The meaning for *attrs* is the same as in :meth:`output`.
 
+   .. deprecated-removed:: 3.15 3.19
+      This method generates a JavaScript snippet to set cookies in the browser,
+      which is no longer considered a standard or recommended approach.
+      Use :meth:`~http.cookies.BaseCookie.output` instead to generate HTTP
+      headers.
+
 
 .. method:: BaseCookie.load(rawdata)
 
@@ -223,6 +229,12 @@ Morsel Objects
 
    The meaning for *attrs* is the same as in :meth:`output`.
 
+   .. deprecated-removed:: 3.15 3.19
+      This method generates a JavaScript snippet to set cookies in the browser,
+      which is no longer considered a standard or recommended approach.
+      Use :meth:`~http.cookies.Morsel.output` instead to generate HTTP
+      headers.
+
 
 .. method:: Morsel.OutputString(attrs=None)
 

Doc/whatsnew/3.15.rst

@@ -1921,6 +1921,16 @@ New deprecations
     (Contributed by Bénédikt Tran in :gh:`134978`.)
 
 
+* :mod:`http.cookies`:
+
+  * :meth:`Morsel.js_output <http.cookies.Morsel.js_output>` and
+    :meth:`BaseCookie.js_output <http.cookies.BaseCookie.js_output>` are
+    deprecated and will be removed in Python 3.19. Use
+    :meth:`Morsel.output <http.cookies.Morsel.output>` or
+    :meth:`BaseCookie.output <http.cookies.BaseCookie.output>` instead.
+    (Contributed by kishorhange111 in :gh:`148849`.)
+
+
 * :mod:`re`:
 
   * :func:`re.match` and :meth:`re.Pattern.match` are now

Lib/http/cookies.py

@@ -132,6 +132,7 @@
 import re
 import string
 import types
+lazy import warnings
 
 __all__ = ["CookieError", "BaseCookie", "SimpleCookie"]
 
@@ -390,7 +391,9 @@ def output(self, attrs=None, header="Set-Cookie:"):
     def __repr__(self):
         return '<%s: %s>' % (self.__class__.__name__, self.OutputString())
 
-    def js_output(self, attrs=None):
+
+    def _js_output(self, attrs=None):
+        """Internal implementation without deprecation warning."""
         import base64
         # Print javascript
         output_string = self.OutputString(attrs)
@@ -407,6 +410,14 @@ def js_output(self, attrs=None):
         </script>
         """ % (output_encoded,)
 
+    def js_output(self, attrs=None):
+        warnings._deprecated(
+            "http.cookies.Morsel.js_output",
+            message=warnings._DEPRECATED_MSG + "; use output() instead",
+            remove=(3, 19),
+        )
+        return self._js_output(attrs)
+
     def OutputString(self, attrs=None):
         # Build up our result
         #
@@ -541,10 +552,15 @@ def __repr__(self):
 
     def js_output(self, attrs=None):
         """Return a string suitable for JavaScript."""
+        warnings._deprecated(
+            "http.cookies.BaseCookie.js_output",
+            message=warnings._DEPRECATED_MSG + "; use output() instead",
+            remove=(3, 19),
+        )
         result = []
         items = sorted(self.items())
         for key, value in items:
-            result.append(value.js_output(attrs))
+            result.append(value._js_output(attrs))
         return _nulljoin(result)
 
     def load(self, rawdata):

Lib/test/test_http_cookies.py

@@ -153,15 +153,17 @@ def test_load(self):
         self.assertEqual(C.output(['path']),
             'Set-Cookie: Customer="WILE_E_COYOTE"; Path=/acme')
         cookie_encoded = base64.b64encode(b'Customer="WILE_E_COYOTE"; Path=/acme; Version=1').decode('ascii')
-        self.assertEqual(C.js_output(), fr"""
+        with self.assertWarnsRegex(DeprecationWarning, r"BaseCookie\.js_output"):
+            self.assertEqual(C.js_output(), fr"""
         <script type="text/javascript">
         <!-- begin hiding
         document.cookie = atob("{cookie_encoded}");
         // end hiding -->
         </script>
         """)
         cookie_encoded = base64.b64encode(b'Customer="WILE_E_COYOTE"; Path=/acme').decode('ascii')
-        self.assertEqual(C.js_output(['path']), fr"""
+        with self.assertWarnsRegex(DeprecationWarning, r"BaseCookie\.js_output"):
+            self.assertEqual(C.js_output(['path']), fr"""
         <script type="text/javascript">
         <!-- begin hiding
         document.cookie = atob("{cookie_encoded}");
@@ -270,15 +272,17 @@ def test_quoted_meta(self):
         self.assertEqual(C.output(['path']),
                          'Set-Cookie: Customer="WILE_E_COYOTE"; Path=/acme')
         expected_encoded_cookie = base64.b64encode(b'Customer=\"WILE_E_COYOTE\"; Path=/acme; Version=1').decode('ascii')
-        self.assertEqual(C.js_output(), fr"""
+        with self.assertWarnsRegex(DeprecationWarning, r"BaseCookie\.js_output"):
+            self.assertEqual(C.js_output(), fr"""
         <script type="text/javascript">
         <!-- begin hiding
         document.cookie = atob("{expected_encoded_cookie}");
         // end hiding -->
         </script>
         """)
         expected_encoded_cookie = base64.b64encode(b'Customer=\"WILE_E_COYOTE\"; Path=/acme').decode('ascii')
-        self.assertEqual(C.js_output(['path']), fr"""
+        with self.assertWarnsRegex(DeprecationWarning, r"BaseCookie\.js_output"):
+            self.assertEqual(C.js_output(['path']), fr"""
         <script type="text/javascript">
         <!-- begin hiding
         document.cookie = atob("{expected_encoded_cookie}");
@@ -382,7 +386,8 @@ def test_setter(self):
         // end hiding -->
         </script>
         """ % (expected_encoded_cookie,)
-            self.assertEqual(M.js_output(), expected_js_output)
+            with self.assertWarnsRegex(DeprecationWarning, r"Morsel\.js_output"):
+                self.assertEqual(M.js_output(), expected_js_output)
         for i in ["foo bar", "foo@bar"]:
             # Try some illegal characters
             self.assertRaises(cookies.CookieError,
@@ -650,16 +655,38 @@ def test_control_characters_output(self):
             cookie = cookies.SimpleCookie()
             cookie["cookie"] = morsel
             with self.assertRaises(cookies.CookieError):
-                cookie.js_output()
+                with self.assertWarnsRegex(DeprecationWarning, r"Morsel\.js_output"):
+                    cookie.js_output()
 
             morsel = cookies.Morsel()
             morsel.set("key", "value", "coded-value")
             morsel._coded_value = c0  # Override private variable.
             cookie = cookies.SimpleCookie()
             cookie["cookie"] = morsel
             with self.assertRaises(cookies.CookieError):
-                cookie.js_output()
+                with self.assertWarnsRegex(DeprecationWarning, r"Morsel\.js_output"):
+                    cookie.js_output()
 
+    def test_morsel_js_output_deprecated(self):
+        morsel = cookies.Morsel()
+        morsel.set("key", "value", "value")
+        with self.assertWarnsRegex(DeprecationWarning, r"Morsel\.js_output") as cm:
+            result = morsel.js_output()
+        self.assertEqual(cm.filename, __file__)
+        self.assertIn("document.cookie", result)
+
+
+    def test_basecookie_js_output_warns_once(self):
+        C = cookies.SimpleCookie()
+        C["key"] = "value"
+        with self.assertWarns(DeprecationWarning) as cm:
+            C.js_output()
+        deprecation_warnings = [
+            w for w in cm.warnings if issubclass(w.category, DeprecationWarning)
+        ]
+        self.assertEqual(len(deprecation_warnings), 1)
+        self.assertRegex(str(deprecation_warnings[0].message), r"BaseCookie\.js_output")
+        self.assertEqual(cm.filename, __file__)
 
 def load_tests(loader, tests, pattern):
     tests.addTest(doctest.DocTestSuite(cookies))

Misc/NEWS.d/next/Library/2026-04-25-12-04-27.gh-issue-148849.Vk6yEW.rst

@@ -0,0 +1,4 @@
+Deprecate :meth:`http.cookies.Morsel.js_output` and
+:meth:`http.cookies.BaseCookie.js_output`, which will be removed in
+Python 3.19. Use :meth:`http.cookies.Morsel.output` or
+:meth:`http.cookies.BaseCookie.output` instead.