Merge branch 'master' into name-prop

Can't remember why I added this one

.gitignore

@@ -23,3 +23,6 @@
 # Macos file system junk
 ._*
 .DS_STORE
+
+# JetBrains IDEs
+/.idea/

CHANGELOG.md

@@ -31,8 +31,14 @@ Making a new release? Simply add the new header with the version and date undern
 
 ## Unreleased
 * Fixed a bug caused by having reference properties (such as `ObjectValue.Value`) that point to an Instance not included in syncback. ([#1179])
+* Implemented support for the "name" property in meta/model JSON files. ([#1187])
+* Fixed instance replacement fallback failing when too many instances needed to be replaced. ([#1192])
+* Fixed a bug where MacOS paths weren't being handled correctly. ([#1201])
 
 [#1179]: https://github.com/rojo-rbx/rojo/pull/1179
+[#1187]: https://github.com/rojo-rbx/rojo/pull/1187
+[#1192]: https://github.com/rojo-rbx/rojo/pull/1192
+[#1201]: https://github.com/rojo-rbx/rojo/pull/1201
 
 ## [7.7.0-rc.1] (November 27th, 2025)
 

Cargo.lock

@@ -1319,6 +1319,7 @@ dependencies = [
  "fs-err",
  "notify",
  "serde",
+ "tempfile",
 ]
 
 [[package]]

crates/memofs/CHANGELOG.md

@@ -1,6 +1,7 @@
 # memofs Changelog
 
 ## Unreleased Changes
+* Added `Vfs::canonicalize`. [#1201]
 
 ## 0.3.1 (2025-11-27)
 * Added `Vfs::exists`. [#1169]

crates/memofs/Cargo.toml

@@ -19,3 +19,6 @@ crossbeam-channel = "0.5.12"
 fs-err = "2.11.0"
 notify = "4.0.17"
 serde = { version = "1.0.197", features = ["derive"] }
+
+[dev-dependencies]
+tempfile = "3.10.1"

crates/memofs/src/in_memory_fs.rs

@@ -232,6 +232,33 @@ impl VfsBackend for InMemoryFs {
         }
     }
 
+    // TODO: We rely on Rojo to prepend cwd to any relative path before storing paths
+    // in MemoFS. The current implementation will error if no prepended absolute path
+    // is found. It really only normalizes paths within the provided path's context.
+    // Example: "/Users/username/project/../other/file.txt" ->
+    // "/Users/username/other/file.txt"
+    // Erroneous example: "/Users/../../other/file.txt" -> "/other/file.txt"
+    // This is not very robust. We should implement proper path normalization here or otherwise
+    // warn if we are missing context and can not fully canonicalize the path correctly.
+    fn canonicalize(&mut self, path: &Path) -> io::Result<PathBuf> {
+        let mut normalized = PathBuf::new();
+        for component in path.components() {
+            match component {
+                std::path::Component::ParentDir => {
+                    normalized.pop();
+                }
+                std::path::Component::CurDir => {}
+                _ => normalized.push(component),
+            }
+        }
+
+        let inner = self.inner.lock().unwrap();
+        match inner.entries.get(&normalized) {
+            Some(_) => Ok(normalized),
+            None => not_found(&normalized),
+        }
+    }
+
     fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
         let inner = self.inner.lock().unwrap();
 

crates/memofs/src/lib.rs

@@ -77,6 +77,7 @@ pub trait VfsBackend: sealed::Sealed + Send + 'static {
     fn metadata(&mut self, path: &Path) -> io::Result<Metadata>;
     fn remove_file(&mut self, path: &Path) -> io::Result<()>;
     fn remove_dir_all(&mut self, path: &Path) -> io::Result<()>;
+    fn canonicalize(&mut self, path: &Path) -> io::Result<PathBuf>;
 
     fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent>;
     fn watch(&mut self, path: &Path) -> io::Result<()>;
@@ -225,6 +226,11 @@ impl VfsInner {
         self.backend.metadata(path)
     }
 
+    fn canonicalize<P: AsRef<Path>>(&mut self, path: P) -> io::Result<PathBuf> {
+        let path = path.as_ref();
+        self.backend.canonicalize(path)
+    }
+
     fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
         self.backend.event_receiver()
     }
@@ -413,6 +419,19 @@ impl Vfs {
         self.inner.lock().unwrap().metadata(path)
     }
 
+    /// Normalize a path via the underlying backend.
+    ///
+    /// Roughly equivalent to [`std::fs::canonicalize`][std::fs::canonicalize]. Relative paths are
+    /// resolved against the backend's current working directory (if applicable) and errors are
+    /// surfaced directly from the backend.
+    ///
+    /// [std::fs::canonicalize]: https://doc.rust-lang.org/stable/std/fs/fn.canonicalize.html
+    #[inline]
+    pub fn canonicalize<P: AsRef<Path>>(&self, path: P) -> io::Result<PathBuf> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().canonicalize(path)
+    }
+
     /// Retrieve a handle to the event receiver for this `Vfs`.
     #[inline]
     pub fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
@@ -540,6 +559,13 @@ impl VfsLock<'_> {
         self.inner.metadata(path)
     }
 
+    /// Normalize a path via the underlying backend.
+    #[inline]
+    pub fn normalize<P: AsRef<Path>>(&mut self, path: P) -> io::Result<PathBuf> {
+        let path = path.as_ref();
+        self.inner.canonicalize(path)
+    }
+
     /// Retrieve a handle to the event receiver for this `Vfs`.
     #[inline]
     pub fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
@@ -555,7 +581,9 @@ impl VfsLock<'_> {
 
 #[cfg(test)]
 mod test {
-    use crate::{InMemoryFs, Vfs, VfsSnapshot};
+    use crate::{InMemoryFs, StdBackend, Vfs, VfsSnapshot};
+    use std::io;
+    use std::path::PathBuf;
 
     /// https://github.com/rojo-rbx/rojo/issues/899
     #[test]
@@ -571,4 +599,62 @@ mod test {
             "bar\nfoo\n\n"
         );
     }
+
+    /// https://github.com/rojo-rbx/rojo/issues/1200
+    #[test]
+    fn canonicalize_in_memory_success() {
+        let mut imfs = InMemoryFs::new();
+        let contents = "Lorem ipsum dolor sit amet.".to_string();
+
+        imfs.load_snapshot("/test/file.txt", VfsSnapshot::file(contents.to_string()))
+            .unwrap();
+
+        let vfs = Vfs::new(imfs);
+
+        assert_eq!(
+            vfs.canonicalize("/test/nested/../file.txt").unwrap(),
+            PathBuf::from("/test/file.txt")
+        );
+        assert_eq!(
+            vfs.read_to_string(vfs.canonicalize("/test/nested/../file.txt").unwrap())
+                .unwrap()
+                .to_string(),
+            contents.to_string()
+        );
+    }
+
+    #[test]
+    fn canonicalize_in_memory_missing_errors() {
+        let imfs = InMemoryFs::new();
+        let vfs = Vfs::new(imfs);
+
+        let err = vfs.canonicalize("test").unwrap_err();
+        assert_eq!(err.kind(), io::ErrorKind::NotFound);
+    }
+
+    #[test]
+    fn canonicalize_std_backend_success() {
+        let contents = "Lorem ipsum dolor sit amet.".to_string();
+        let dir = tempfile::tempdir().unwrap();
+        let file_path = dir.path().join("file.txt");
+        fs_err::write(&file_path, contents.to_string()).unwrap();
+
+        let vfs = Vfs::new(StdBackend::new());
+        let canonicalized = vfs.canonicalize(&file_path).unwrap();
+        assert_eq!(canonicalized, file_path.canonicalize().unwrap());
+        assert_eq!(
+            vfs.read_to_string(&canonicalized).unwrap().to_string(),
+            contents.to_string()
+        );
+    }
+
+    #[test]
+    fn canonicalize_std_backend_missing_errors() {
+        let dir = tempfile::tempdir().unwrap();
+        let file_path = dir.path().join("test");
+
+        let vfs = Vfs::new(StdBackend::new());
+        let err = vfs.canonicalize(&file_path).unwrap_err();
+        assert_eq!(err.kind(), io::ErrorKind::NotFound);
+    }
 }

crates/memofs/src/noop_backend.rs

@@ -1,5 +1,5 @@
 use std::io;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 
 use crate::{Metadata, ReadDir, VfsBackend, VfsEvent};
 
@@ -50,6 +50,10 @@ impl VfsBackend for NoopBackend {
         Err(io::Error::other("NoopBackend doesn't do anything"))
     }
 
+    fn canonicalize(&mut self, _path: &Path) -> io::Result<PathBuf> {
+        Err(io::Error::other("NoopBackend doesn't do anything"))
+    }
+
     fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
         crossbeam_channel::never()
     }

crates/memofs/src/std_backend.rs

@@ -106,6 +106,10 @@ impl VfsBackend for StdBackend {
         })
     }
 
+    fn canonicalize(&mut self, path: &Path) -> io::Result<PathBuf> {
+        fs_err::canonicalize(path)
+    }
+
     fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
         self.watcher_receiver.clone()
     }

plugin/src/ApiContext.lua

@@ -290,31 +290,39 @@ function ApiContext:open(id)
 end
 
 function ApiContext:serialize(ids: { string })
-	local url = ("%s/api/serialize/%s"):format(self.__baseUrl, table.concat(ids, ","))
+	local url = ("%s/api/serialize"):format(self.__baseUrl)
+	local request_body = Http.jsonEncode({ sessionId = self.__sessionId, ids = ids })
 
-	return Http.get(url):andThen(rejectFailedRequests):andThen(Http.Response.json):andThen(function(body)
-		if body.sessionId ~= self.__sessionId then
-			return Promise.reject("Server changed ID")
-		end
+	return Http.post(url, request_body)
+		:andThen(rejectFailedRequests)
+		:andThen(Http.Response.json)
+		:andThen(function(response_body)
+			if response_body.sessionId ~= self.__sessionId then
+				return Promise.reject("Server changed ID")
+			end
 
-		assert(validateApiSerialize(body))
+			assert(validateApiSerialize(response_body))
 
-		return body
-	end)
+			return response_body
+		end)
 end
 
 function ApiContext:refPatch(ids: { string })
-	local url = ("%s/api/ref-patch/%s"):format(self.__baseUrl, table.concat(ids, ","))
+	local url = ("%s/api/ref-patch"):format(self.__baseUrl)
+	local request_body = Http.jsonEncode({ sessionId = self.__sessionId, ids = ids })
 
-	return Http.get(url):andThen(rejectFailedRequests):andThen(Http.Response.json):andThen(function(body)
-		if body.sessionId ~= self.__sessionId then
-			return Promise.reject("Server changed ID")
-		end
+	return Http.post(url, request_body)
+		:andThen(rejectFailedRequests)
+		:andThen(Http.Response.json)
+		:andThen(function(response_body)
+			if response_body.sessionId ~= self.__sessionId then
+				return Promise.reject("Server changed ID")
+			end
 
-		assert(validateApiRefPatch(body))
+			assert(validateApiRefPatch(response_body))
 
-		return body
-	end)
+			return response_body
+		end)
 end
 
 return ApiContext

src/change_processor.rs

@@ -1,12 +1,12 @@
-use std::{
-    fs,
-    sync::{Arc, Mutex},
-};
-
 use crossbeam_channel::{select, Receiver, RecvError, Sender};
 use jod_thread::JoinHandle;
 use memofs::{IoResultExt, Vfs, VfsEvent};
 use rbx_dom_weak::types::{Ref, Variant};
+use std::path::PathBuf;
+use std::{
+    fs,
+    sync::{Arc, Mutex},
+};
 
 use crate::{
     message_queue::MessageQueue,
@@ -114,6 +114,49 @@ struct JobThreadContext {
 }
 
 impl JobThreadContext {
+    /// Computes and applies patches to the DOM for a given file path.
+    ///
+    /// This function finds the nearest ancestor to the given path that has associated instances
+    /// in the tree.
+    /// It then computes and applies changes for each affected instance ID and
+    /// returns a vector of applied patch sets.
+    fn apply_patches(&self, path: PathBuf) -> Vec<AppliedPatchSet> {
+        let mut tree = self.tree.lock().unwrap();
+        let mut applied_patches = Vec::new();
+
+        // Find the nearest ancestor to this path that has
+        // associated instances in the tree. This helps make sure
+        // that we handle additions correctly, especially if we
+        // receive events for descendants of a large tree being
+        // created all at once.
+        let mut current_path = path.as_path();
+        let affected_ids = loop {
+            let ids = tree.get_ids_at_path(current_path);
+
+            log::trace!("Path {} affects IDs {:?}", current_path.display(), ids);
+
+            if !ids.is_empty() {
+                break ids.to_vec();
+            }
+
+            log::trace!("Trying parent path...");
+            match current_path.parent() {
+                Some(parent) => current_path = parent,
+                None => break Vec::new(),
+            }
+        };
+
+        for id in affected_ids {
+            if let Some(patch) = compute_and_apply_changes(&mut tree, &self.vfs, id) {
+                if !patch.is_empty() {
+                    applied_patches.push(patch);
+                }
+            }
+        }
+
+        applied_patches
+    }
+
     fn handle_vfs_event(&self, event: VfsEvent) {
         log::trace!("Vfs event: {:?}", event);
 
@@ -125,41 +168,16 @@ impl JobThreadContext {
         // For a given VFS event, we might have many changes to different parts
         // of the tree. Calculate and apply all of these changes.
         let applied_patches = match event {
-            VfsEvent::Create(path) | VfsEvent::Remove(path) | VfsEvent::Write(path) => {
-                let mut tree = self.tree.lock().unwrap();
-                let mut applied_patches = Vec::new();
-
-                // Find the nearest ancestor to this path that has
-                // associated instances in the tree. This helps make sure
-                // that we handle additions correctly, especially if we
-                // receive events for descendants of a large tree being
-                // created all at once.
-                let mut current_path = path.as_path();
-                let affected_ids = loop {
-                    let ids = tree.get_ids_at_path(current_path);
-
-                    log::trace!("Path {} affects IDs {:?}", current_path.display(), ids);
-
-                    if !ids.is_empty() {
-                        break ids.to_vec();
-                    }
-
-                    log::trace!("Trying parent path...");
-                    match current_path.parent() {
-                        Some(parent) => current_path = parent,
-                        None => break Vec::new(),
-                    }
-                };
-
-                for id in affected_ids {
-                    if let Some(patch) = compute_and_apply_changes(&mut tree, &self.vfs, id) {
-                        if !patch.is_empty() {
-                            applied_patches.push(patch);
-                        }
-                    }
-                }
-
-                applied_patches
+            VfsEvent::Create(path) | VfsEvent::Write(path) => {
+                self.apply_patches(self.vfs.canonicalize(&path).unwrap())
+            }
+            VfsEvent::Remove(path) => {
+                // MemoFS does not track parent removals yet, so we can canonicalize
+                // the parent path safely and then append the removed path's file name.
+                let parent = path.parent().unwrap();
+                let file_name = path.file_name().unwrap();
+                let parent_normalized = self.vfs.canonicalize(parent).unwrap();
+                self.apply_patches(parent_normalized.join(file_name))
             }
             _ => {
                 log::warn!("Unhandled VFS event: {:?}", event);

src/snapshot_middleware/csv.rs

@@ -42,7 +42,7 @@ pub fn snapshot_csv(
         .metadata(
             InstanceMetadata::new()
                 .instigating_source(path)
-                .relevant_paths(vec![path.to_path_buf()]),
+                .relevant_paths(vec![vfs.canonicalize(path)?]),
         );
 
     AdjacentMetadata::read_and_apply_all(vfs, path, name, &mut snapshot)?;

src/snapshot_middleware/dir.rs

@@ -62,18 +62,19 @@ pub fn snapshot_dir_no_meta(
         }
     }
 
+    let normalized_path = vfs.canonicalize(path)?;
     let relevant_paths = vec![
-        path.to_path_buf(),
+        normalized_path.clone(),
         // TODO: We shouldn't need to know about Lua existing in this
         // middleware. Should we figure out a way for that function to add
         // relevant paths to this middleware?
-        path.join("init.lua"),
-        path.join("init.luau"),
-        path.join("init.server.lua"),
-        path.join("init.server.luau"),
-        path.join("init.client.lua"),
-        path.join("init.client.luau"),
-        path.join("init.csv"),
+        normalized_path.join("init.lua"),
+        normalized_path.join("init.luau"),
+        normalized_path.join("init.server.lua"),
+        normalized_path.join("init.server.luau"),
+        normalized_path.join("init.client.lua"),
+        normalized_path.join("init.client.luau"),
+        normalized_path.join("init.csv"),
     ];
 
     let snapshot = InstanceSnapshot::new()

src/snapshot_middleware/json.rs

@@ -32,7 +32,7 @@ pub fn snapshot_json(
         .metadata(
             InstanceMetadata::new()
                 .instigating_source(path)
-                .relevant_paths(vec![path.to_path_buf()])
+                .relevant_paths(vec![vfs.canonicalize(path)?])
                 .context(context),
         );
 

src/snapshot_middleware/json_model.rs

@@ -53,7 +53,7 @@ pub fn snapshot_json_model(
     snapshot.metadata = snapshot
         .metadata
         .instigating_source(path)
-        .relevant_paths(vec![path.to_path_buf()])
+        .relevant_paths(vec![vfs.canonicalize(path)?])
         .context(context)
         .specified_id(id)
         .schema(schema)

src/snapshot_middleware/lua.rs

@@ -88,7 +88,7 @@ pub fn snapshot_lua(
         .metadata(
             InstanceMetadata::new()
                 .instigating_source(path)
-                .relevant_paths(vec![path.to_path_buf()])
+                .relevant_paths(vec![vfs.canonicalize(path)?])
                 .context(context),
         );
 

src/snapshot_middleware/rbxm.rs

@@ -28,7 +28,7 @@ pub fn snapshot_rbxm(
             .metadata(
                 InstanceMetadata::new()
                     .instigating_source(path)
-                    .relevant_paths(vec![path.to_path_buf()])
+                    .relevant_paths(vec![vfs.canonicalize(path)?])
                     .context(context),
             );
 

src/snapshot_middleware/rbxmx.rs

@@ -31,7 +31,7 @@ pub fn snapshot_rbxmx(
             .metadata(
                 InstanceMetadata::new()
                     .instigating_source(path)
-                    .relevant_paths(vec![path.to_path_buf()])
+                    .relevant_paths(vec![vfs.canonicalize(path)?])
                     .context(context),
             );
 

src/snapshot_middleware/toml.rs

@@ -31,7 +31,7 @@ pub fn snapshot_toml(
         .metadata(
             InstanceMetadata::new()
                 .instigating_source(path)
-                .relevant_paths(vec![path.to_path_buf()])
+                .relevant_paths(vec![vfs.canonicalize(path)?])
                 .context(context),
         );
 

src/snapshot_middleware/txt.rs

@@ -28,7 +28,7 @@ pub fn snapshot_txt(
         .metadata(
             InstanceMetadata::new()
                 .instigating_source(path)
-                .relevant_paths(vec![path.to_path_buf()])
+                .relevant_paths(vec![vfs.canonicalize(path)?])
                 .context(context),
         );
 

src/snapshot_middleware/yaml.rs

@@ -37,7 +37,7 @@ pub fn snapshot_yaml(
         .metadata(
             InstanceMetadata::new()
                 .instigating_source(path)
-                .relevant_paths(vec![path.to_path_buf()])
+                .relevant_paths(vec![vfs.canonicalize(path)?])
                 .context(context),
         );
 

src/syncback/mod.rs

@@ -301,7 +301,6 @@ pub fn get_best_middleware(snapshot: &SyncbackSnapshot) -> Middleware {
     static JSON_MODEL_CLASSES: OnceLock<HashSet<&str>> = OnceLock::new();
     let json_model_classes = JSON_MODEL_CLASSES.get_or_init(|| {
         [
-            "Actor",
             "Sound",
             "SoundGroup",
             "Sky",
@@ -334,6 +333,8 @@ pub fn get_best_middleware(snapshot: &SyncbackSnapshot) -> Middleware {
         return override_middleware;
     } else if let Some(old_middleware) = old_middleware {
         return old_middleware;
+    } else if json_model_classes.contains(inst.class.as_str()) {
+        middleware = Middleware::JsonModel;
     } else {
         middleware = match inst.class.as_str() {
             "Folder" | "Configuration" | "Tool" => Middleware::Dir,
@@ -344,7 +345,6 @@ pub fn get_best_middleware(snapshot: &SyncbackSnapshot) -> Middleware {
             "LocalizationTable" => Middleware::Csv,
             // This isn't the ideal way to handle this but it works.
             name if name.ends_with("Value") => Middleware::JsonModel,
-            _ if json_model_classes.contains(inst.class.as_str()) => Middleware::JsonModel,
             _ => Middleware::Rbxm,
         }
     }
@@ -360,28 +360,6 @@ pub fn get_best_middleware(snapshot: &SyncbackSnapshot) -> Middleware {
         }
     }
 
-    // If the name is invalid but the instance has no descendants and isn't a
-    // folder/config/tool, prefer slugified files over creating a directory.
-    // Only promote to directory when there are children (or dir-like classes).
-    if crate::syncback::file_names::validate_file_name(&inst.name).is_err() {
-        middleware = match middleware {
-            Middleware::ServerScript | Middleware::ClientScript | Middleware::ModuleScript
-                if inst.children().is_empty() =>
-            {
-                middleware
-            }
-            Middleware::JsonModel | Middleware::Text if inst.children().is_empty() => middleware,
-            _ => match middleware {
-                Middleware::ServerScript => Middleware::ServerScriptDir,
-                Middleware::ClientScript => Middleware::ClientScriptDir,
-                Middleware::ModuleScript => Middleware::ModuleScriptDir,
-                Middleware::Csv => Middleware::CsvDir,
-                Middleware::JsonModel | Middleware::Text => Middleware::Dir,
-                _ => middleware,
-            },
-        }
-    }
-
     if middleware == Middleware::Rbxm {
         middleware = match env::var(DEBUG_MODEL_FORMAT_VAR) {
             Ok(value) if value == "1" => Middleware::Rbxmx,

src/web/api.rs

@@ -1,13 +1,7 @@
 //! Defines Rojo's HTTP API, all under /api. These endpoints generally return
 //! JSON.
 
-use std::{
-    collections::{HashMap, HashSet},
-    fs,
-    path::PathBuf,
-    str::FromStr,
-    sync::Arc,
-};
+use std::{collections::HashMap, fs, path::PathBuf, str::FromStr, sync::Arc};
 
 use futures::{sink::SinkExt, stream::StreamExt};
 use hyper::{body, Body, Method, Request, Response, StatusCode};
@@ -30,7 +24,10 @@ use crate::{
         },
         util::{json, json_ok},
     },
-    web_api::{BufferEncode, InstanceUpdate, RefPatchResponse, SerializeResponse},
+    web_api::{
+        BufferEncode, InstanceUpdate, RefPatchRequest, RefPatchResponse, SerializeRequest,
+        SerializeResponse,
+    },
 };
 
 pub async fn call(serve_session: Arc<ServeSession>, mut request: Request<Body>) -> Response<Body> {
@@ -53,12 +50,8 @@ pub async fn call(serve_session: Arc<ServeSession>, mut request: Request<Body>)
                 )
             }
         }
-        (&Method::GET, path) if path.starts_with("/api/serialize/") => {
-            service.handle_api_serialize(request).await
-        }
-        (&Method::GET, path) if path.starts_with("/api/ref-patch/") => {
-            service.handle_api_ref_patch(request).await
-        }
+        (&Method::POST, "/api/serialize") => service.handle_api_serialize(request).await,
+        (&Method::POST, "/api/ref-patch") => service.handle_api_ref_patch(request).await,
 
         (&Method::POST, path) if path.starts_with("/api/open/") => {
             service.handle_api_open(request).await
@@ -229,22 +222,30 @@ impl ApiService {
     /// that correspond to the requested Instances. These values have their
     /// `Value` property set to point to the requested Instance.
     async fn handle_api_serialize(&self, request: Request<Body>) -> Response<Body> {
-        let argument = &request.uri().path()["/api/serialize/".len()..];
-        let requested_ids: Result<Vec<Ref>, _> = argument.split(',').map(Ref::from_str).collect();
+        let session_id = self.serve_session.session_id();
+        let body = body::to_bytes(request.into_body()).await.unwrap();
 
-        let requested_ids = match requested_ids {
-            Ok(ids) => ids,
-            Err(_) => {
+        let request: SerializeRequest = match json::from_slice(&body) {
+            Ok(request) => request,
+            Err(err) => {
                 return json(
-                    ErrorResponse::bad_request("Malformed ID list"),
+                    ErrorResponse::bad_request(format!("Invalid body: {}", err)),
                     StatusCode::BAD_REQUEST,
                 );
             }
         };
+
+        if request.session_id != session_id {
+            return json(
+                ErrorResponse::bad_request("Wrong session ID"),
+                StatusCode::BAD_REQUEST,
+            );
+        }
+
         let mut response_dom = WeakDom::new(InstanceBuilder::new("Folder"));
 
         let tree = self.serve_session.tree();
-        for id in &requested_ids {
+        for id in &request.ids {
             if let Some(instance) = tree.get_instance(*id) {
                 let clone = response_dom.insert(
                     Ref::none(),
@@ -290,20 +291,26 @@ impl ApiService {
     /// and referent properties need to be updated after the serialize
     /// endpoint is used.
     async fn handle_api_ref_patch(self, request: Request<Body>) -> Response<Body> {
-        let argument = &request.uri().path()["/api/ref-patch/".len()..];
-        let requested_ids: Result<HashSet<Ref>, _> =
-            argument.split(',').map(Ref::from_str).collect();
+        let session_id = self.serve_session.session_id();
+        let body = body::to_bytes(request.into_body()).await.unwrap();
 
-        let requested_ids = match requested_ids {
-            Ok(ids) => ids,
-            Err(_) => {
+        let request: RefPatchRequest = match json::from_slice(&body) {
+            Ok(request) => request,
+            Err(err) => {
                 return json(
-                    ErrorResponse::bad_request("Malformed ID list"),
+                    ErrorResponse::bad_request(format!("Invalid body: {}", err)),
                     StatusCode::BAD_REQUEST,
                 );
             }
         };
 
+        if request.session_id != session_id {
+            return json(
+                ErrorResponse::bad_request("Wrong session ID"),
+                StatusCode::BAD_REQUEST,
+            );
+        }
+
         let mut instance_updates: HashMap<Ref, InstanceUpdate> = HashMap::new();
 
         let tree = self.serve_session.tree();
@@ -312,7 +319,7 @@ impl ApiService {
                 let Variant::Ref(prop_value) = prop_value else {
                     continue;
                 };
-                if let Some(target_id) = requested_ids.get(prop_value) {
+                if let Some(target_id) = request.ids.get(prop_value) {
                     let instance_id = instance.id();
                     let update =
                         instance_updates

src/web/interface.rs

@@ -238,6 +238,13 @@ pub struct OpenResponse {
     pub session_id: SessionId,
 }
 
+#[derive(Debug, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct SerializeRequest {
+    pub session_id: SessionId,
+    pub ids: Vec<Ref>,
+}
+
 #[derive(Debug, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
 pub struct SerializeResponse {
@@ -269,6 +276,13 @@ impl BufferEncode {
     }
 }
 
+#[derive(Debug, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct RefPatchRequest {
+    pub session_id: SessionId,
+    pub ids: HashSet<Ref>,
+}
+
 #[derive(Debug, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
 pub struct RefPatchResponse<'a> {

tests/rojo_test/serve_util.rs

@@ -1,5 +1,4 @@
 use std::{
-    fmt::Write as _,
     fs,
     path::{Path, PathBuf},
     process::Command,
@@ -13,8 +12,12 @@ use rbx_dom_weak::types::Ref;
 
 use tempfile::{tempdir, TempDir};
 
-use librojo::web_api::{
-    ReadResponse, SerializeResponse, ServerInfoResponse, SocketPacket, SocketPacketType,
+use librojo::{
+    web_api::{
+        ReadResponse, SerializeRequest, SerializeResponse, ServerInfoResponse, SocketPacket,
+        SocketPacketType,
+    },
+    SessionId,
 };
 use rojo_insta_ext::RedactionMap;
 
@@ -226,16 +229,19 @@ impl TestServeSession {
         }
     }
 
-    pub fn get_api_serialize(&self, ids: &[Ref]) -> Result<SerializeResponse, reqwest::Error> {
-        let mut id_list = String::with_capacity(ids.len() * 33);
-        for id in ids {
-            write!(id_list, "{id},").unwrap();
-        }
-        id_list.pop();
+    pub fn get_api_serialize(
+        &self,
+        ids: &[Ref],
+        session_id: SessionId,
+    ) -> Result<SerializeResponse, reqwest::Error> {
+        let client = reqwest::blocking::Client::new();
+        let url = format!("http://localhost:{}/api/serialize", self.port);
+        let body = serde_json::to_string(&SerializeRequest {
+            session_id,
+            ids: ids.to_vec(),
+        });
 
-        let url = format!("http://localhost:{}/api/serialize/{}", self.port, id_list);
-
-        reqwest::blocking::get(url)?.json()
+        client.post(url).body((body).unwrap()).send()?.json()
     }
 }
 

tests/tests/serve.rs

@@ -646,7 +646,7 @@ fn meshpart_with_id() {
             .unwrap();
 
         let serialize_response = session
-            .get_api_serialize(&[*meshpart, *objectvalue])
+            .get_api_serialize(&[*meshpart, *objectvalue], info.session_id)
             .unwrap();
 
         // We don't assert a snapshot on the SerializeResponse because the model includes the
@@ -673,7 +673,9 @@ fn forced_parent() {
             read_response.intern_and_redact(&mut redactions, root_id)
         );
 
-        let serialize_response = session.get_api_serialize(&[root_id]).unwrap();
+        let serialize_response = session
+            .get_api_serialize(&[root_id], info.session_id)
+            .unwrap();
 
         assert_eq!(serialize_response.session_id, info.session_id);