Found a better way of handling extra keys without dealing with unsafe casts.

Author: hikingc

matrix-sdk-core/src/main/java/io/github/hikingc/matrixsdk/api/well_known/PolicyServerInformation.java

@@ -1,19 +1,17 @@
 package io.github.hikingc.matrixsdk.api.well_known;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
 
-import java.util.HashMap;
 import java.util.Map;
 
-public record PolicyServerInformation(Map<String, Object> publicKeys, Map<String, Object> otherProperties) {
-    /// Deserialization helper to accommodate additional unknown fields.
-    ///
-    /// @param raw input key-values from a response.
-    /// @return deserialized [PolicyServerInformation] with corresponding values.
+public record PolicyServerInformation(
+        @JsonProperty(value = "public_keys", required = true) Map<String, String> publicKeys,
+        Map<String, Object> extraFields) {
+
     @JsonCreator
-    public static PolicyServerInformation of(Map<String, Object> raw) {
-        Map<String, Object> copy = new HashMap<>(raw);
-        var room = (Map<String, Object>) copy.remove("public_keys");
-        return new PolicyServerInformation(room, Map.copyOf(copy));
+    public PolicyServerInformation(
+            @JsonProperty(value = "public_keys", required = true) Map<String, String> publicKeys) {
+        this(Map.copyOf(publicKeys), Map.of());
     }
 }

matrix-sdk-core/src/test/java/io/github/hikingc/matrixsdk/api/MatrixDiscoveryTest.java

@@ -98,5 +98,6 @@ void getFetchPolicyServer_ReturnAnObject() {
                                                         """)));
         var response = matrixDiscovery.fetchPolicyServer();
         assertThat(response).isNotNull();
+        assertThat(response.publicKeys().get("ed25519")).contains("6yhHGKhCiXTSEN2ksjV7kX_N6rBQZ3Xb-M7LlC6NS-s");
     }
 }