From 42d0dcf88c4a08bc90fad2daaf3f2262c901352f Mon Sep 17 00:00:00 2001
From: Maurus Decimus <11444311+mdecimus@users.noreply.github.com>
Date: Thu, 18 Jun 2026 15:43:18 +0200
Subject: [PATCH] Fix JMAP: `filter: null` rejected as `notRequest` on `/query`
 and `/queryChanges`

---
 CHANGELOG.md                          |  3 ++-
 crates/jmap-proto/src/method/query.rs | 16 +++++++++++++++-
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7aa4306e..ba786c2f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,7 +17,8 @@ If you are upgrading from v0.16.x, replace the binary (or run `docker pull`). If
 ## Fixed
 - JMAP:
   - Default calendars and address books are not subscribed by default.
-  - Do not reject an unchanged immutable `id` property.
+  - Unchanged immutable `id` property is rejected on `/set`.
+  - `filter: null` rejected as `notRequest` on `/query` and `/queryChanges`.
 - OIDC: Add default domain name to groups that are not email addresses.
 - RocksDB: Enable blob garbage collection to reclaim disk space from deleted blobs.
 
diff --git a/crates/jmap-proto/src/method/query.rs b/crates/jmap-proto/src/method/query.rs
index cc094478..886c9bfd 100644
--- a/crates/jmap-proto/src/method/query.rs
+++ b/crates/jmap-proto/src/method/query.rs
@@ -195,6 +195,20 @@ where
                 write!(formatter, "a filter object")
             }
 
+            fn visit_unit<E>(self) -> Result<(), E>
+            where
+                E: de::Error,
+            {
+                Ok(())
+            }
+
+            fn visit_none<E>(self) -> Result<(), E>
+            where
+                E: de::Error,
+            {
+                Ok(())
+            }
+
             fn visit_map<V>(self, mut map: V) -> Result<(), V::Error>
             where
                 V: MapAccess<'de>,
@@ -261,7 +275,7 @@ where
             }
         }
 
-        deserializer.deserialize_map(FilterVisitor(self.0))
+        deserializer.deserialize_any(FilterVisitor(self.0))
     }
 }