From 57a5886aef4887ce4bfce5e5f95572c61cf80470 Mon Sep 17 00:00:00 2001
From: Patrick Cloke <patrickc@matrix.org>
Date: Tue, 23 Feb 2021 10:30:44 -0500
Subject: [PATCH 1/2] Add back the deprecated SAML endpoint.

---
 synapse/rest/synapse/client/__init__.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/synapse/rest/synapse/client/__init__.py b/synapse/rest/synapse/client/__init__.py
index 8588b6d271cc..9eeb970580ed 100644
--- a/synapse/rest/synapse/client/__init__.py
+++ b/synapse/rest/synapse/client/__init__.py
@@ -54,7 +54,12 @@ def build_synapse_client_resource_tree(hs: "HomeServer") -> Mapping[str, Resourc
     if hs.config.saml2_enabled:
         from synapse.rest.synapse.client.saml2 import SAML2Resource
 
-        resources["/_synapse/client/saml2"] = SAML2Resource(hs)
+        res = SAML2Resource(hs)
+        resources["/_synapse/client/saml2"] = res
+
+        # This is also mounted under '/_matrix' for backwards-compatibility.
+        # To be removed in Synapse v1.32.0.
+        resources["/_matrix/saml2"] = res
 
     return resources
 

From 0c10b9842d51e1b9c44fdfcc9e63d4e913b14f7c Mon Sep 17 00:00:00 2001
From: Patrick Cloke <patrickc@matrix.org>
Date: Tue, 23 Feb 2021 11:01:21 -0500
Subject: [PATCH 2/2] Newsfragment

---
 changelog.d/9474.misc | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changelog.d/9474.misc

diff --git a/changelog.d/9474.misc b/changelog.d/9474.misc
new file mode 100644
index 000000000000..1b9a235292c7
--- /dev/null
+++ b/changelog.d/9474.misc
@@ -0,0 +1 @@
+Revert change in v1.28.0rc1 to remove the deprecated SAML endpoint.