fix: update server version endpoint with optional python version

Signed-off-by: Hanadi92 <hanadi.tamimi@gmail.com>

src/version/get_server_version/v1.rs

@@ -1,6 +1,7 @@
-//! [GET /_synapse/admin/v1/server_version](https://github.com/matrix-org/synapse/blob/master/docs/admin_api/version_api.rst)
+//! [GET /_synapse/admin/v1/server_version](https://github.com/element-hq/synapse/blob/develop/docs/admin_api/version_api.md)
 
 use ruma::api::{metadata, request, response, Metadata};
+use serde::{Deserialize, Serialize};
 
 const METADATA: Metadata = metadata! {
     method: GET,
@@ -16,12 +17,15 @@ const METADATA: Metadata = metadata! {
 pub struct Request {}
 
 #[response]
+#[derive(Serialize, Deserialize)]
 pub struct Response {
     /// The Synapse version.
     pub server_version: String,
 
     /// The Python version.
-    pub python_version: String,
+    /// Optional since Synapse 1.94.0
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub python_version: Option<String>,
 }
 
 impl Request {
@@ -33,7 +37,51 @@ impl Request {
 
 impl Response {
     /// Creates a `Response` with the given Synapse and Python versions.
-    pub fn new(server_version: String, python_version: String) -> Self {
+    pub fn new(server_version: String, python_version: Option<String>) -> Self {
         Self { server_version, python_version }
     }
 }
+
+#[test]
+fn test_response_with_python_version() {
+    use serde_json;
+
+    let server_version = "1.2.3".to_string();
+    let python_version = Some("4.5.6".to_string());
+
+    // create response case
+    let response = Response::new(server_version.clone(), python_version.clone());
+    assert_eq!(response.server_version, server_version);
+    assert_eq!(response.python_version, python_version);
+
+    // serialization case
+    let serialized = serde_json::to_string(&response).unwrap();
+    assert_eq!(serialized, "{\"server_version\":\"1.2.3\",\"python_version\":\"4.5.6\"}");
+
+    // deserialization case
+    let deserialized: Response = serde_json::from_str(&serialized).unwrap();
+    assert_eq!(deserialized.server_version, "1.2.3");
+    assert_eq!(deserialized.python_version, Some("4.5.6".to_string()));
+}
+
+#[test]
+fn test_response_without_python_version() {
+    use serde_json;
+
+    let server_version = "1.2.3".to_string();
+    let python_version = None;
+
+    // create response case
+    let response = Response::new(server_version.clone(), python_version);
+    assert_eq!(response.server_version, server_version);
+    assert!(response.python_version.is_none());
+
+    // serialization case
+    let serialized = serde_json::to_string(&response).unwrap();
+    assert_eq!(serialized, "{\"server_version\":\"1.2.3\"}");
+
+    // deserialization case
+    let deserialized: Response = serde_json::from_str(&serialized).unwrap();
+    assert_eq!(deserialized.server_version, "1.2.3");
+    assert!(deserialized.python_version.is_none());
+}