Route local-only app-server gating through processors (#23551)

## Summary
- move local-only app-server gating out of `MessageProcessor`
- let `fs/*`, `command/exec`, and `process/spawn` resolve local
availability inside their owning processors
- keep `fs/*` mounted for the future environment-param path while
preserving current no-local error behavior

## Validation
- not run locally per Codex repo guidance

codex-rs/app-server/src/request_processors/command_exec_processor.rs

@@ -6,6 +6,7 @@ pub(crate) struct CommandExecRequestProcessor {
     config: Arc<Config>,
     outgoing: Arc<OutgoingMessageSender>,
     config_manager: ConfigManager,
+    environment_manager: Arc<EnvironmentManager>,
     command_exec_manager: CommandExecManager,
 }
 
@@ -15,12 +16,14 @@ impl CommandExecRequestProcessor {
         config: Arc<Config>,
         outgoing: Arc<OutgoingMessageSender>,
         config_manager: ConfigManager,
+        environment_manager: Arc<EnvironmentManager>,
     ) -> Self {
         Self {
             arg0_paths,
             config,
             outgoing,
             config_manager,
+            environment_manager,
             command_exec_manager: CommandExecManager::default(),
         }
     }
@@ -30,6 +33,7 @@ impl CommandExecRequestProcessor {
         request_id: &ConnectionRequestId,
         params: CommandExecParams,
     ) -> Result<Option<ClientResponsePayload>, JSONRPCErrorError> {
+        self.require_local_environment()?;
         self.exec_one_off_command(request_id, params)
             .await
             .map(|()| None)
@@ -74,6 +78,14 @@ impl CommandExecRequestProcessor {
             .await;
     }
 
+    fn require_local_environment(&self) -> Result<(), JSONRPCErrorError> {
+        self.environment_manager
+            .try_local_environment()
+            .is_some()
+            .then_some(())
+            .ok_or_else(|| internal_error("local environment is not configured"))
+    }
+
     async fn exec_one_off_command(
         &self,
         request_id: &ConnectionRequestId,

codex-rs/app-server/src/request_processors/fs_processor.rs

@@ -26,6 +26,7 @@ use codex_app_server_protocol::FsWriteFileResponse;
 use codex_app_server_protocol::JSONRPCErrorError;
 use codex_exec_server::CopyOptions;
 use codex_exec_server::CreateDirectoryOptions;
+use codex_exec_server::EnvironmentManager;
 use codex_exec_server::ExecutorFileSystem;
 use codex_exec_server::RemoveOptions;
 use std::io;
@@ -33,21 +34,28 @@ use std::sync::Arc;
 
 #[derive(Clone)]
 pub(crate) struct FsRequestProcessor {
-    file_system: Arc<dyn ExecutorFileSystem>,
+    environment_manager: Arc<EnvironmentManager>,
     fs_watch_manager: FsWatchManager,
 }
 
 impl FsRequestProcessor {
     pub(crate) fn new(
-        file_system: Arc<dyn ExecutorFileSystem>,
+        environment_manager: Arc<EnvironmentManager>,
         fs_watch_manager: FsWatchManager,
     ) -> Self {
         Self {
-            file_system,
+            environment_manager,
             fs_watch_manager,
         }
     }
 
+    fn file_system(&self) -> Result<Arc<dyn ExecutorFileSystem>, JSONRPCErrorError> {
+        self.environment_manager
+            .try_local_environment()
+            .map(|environment| environment.get_filesystem())
+            .ok_or_else(|| internal_error("local filesystem is not configured"))
+    }
+
     pub(crate) async fn connection_closed(&self, connection_id: ConnectionId) {
         self.fs_watch_manager.connection_closed(connection_id).await;
     }
@@ -57,7 +65,7 @@ impl FsRequestProcessor {
         params: FsReadFileParams,
     ) -> Result<FsReadFileResponse, JSONRPCErrorError> {
         let bytes = self
-            .file_system
+            .file_system()?
             .read_file(&params.path, /*sandbox*/ None)
             .await
             .map_err(map_fs_error)?;
@@ -75,7 +83,7 @@ impl FsRequestProcessor {
                 "fs/writeFile requires valid base64 dataBase64: {err}"
             ))
         })?;
-        self.file_system
+        self.file_system()?
             .write_file(&params.path, bytes, /*sandbox*/ None)
             .await
             .map_err(map_fs_error)?;
@@ -86,7 +94,7 @@ impl FsRequestProcessor {
         &self,
         params: FsCreateDirectoryParams,
     ) -> Result<FsCreateDirectoryResponse, JSONRPCErrorError> {
-        self.file_system
+        self.file_system()?
             .create_directory(
                 &params.path,
                 CreateDirectoryOptions {
@@ -104,7 +112,7 @@ impl FsRequestProcessor {
         params: FsGetMetadataParams,
     ) -> Result<FsGetMetadataResponse, JSONRPCErrorError> {
         let metadata = self
-            .file_system
+            .file_system()?
             .get_metadata(&params.path, /*sandbox*/ None)
             .await
             .map_err(map_fs_error)?;
@@ -122,7 +130,7 @@ impl FsRequestProcessor {
         params: FsReadDirectoryParams,
     ) -> Result<FsReadDirectoryResponse, JSONRPCErrorError> {
         let entries = self
-            .file_system
+            .file_system()?
             .read_directory(&params.path, /*sandbox*/ None)
             .await
             .map_err(map_fs_error)?;
@@ -142,7 +150,7 @@ impl FsRequestProcessor {
         &self,
         params: FsRemoveParams,
     ) -> Result<FsRemoveResponse, JSONRPCErrorError> {
-        self.file_system
+        self.file_system()?
             .remove(
                 &params.path,
                 RemoveOptions {
@@ -160,7 +168,7 @@ impl FsRequestProcessor {
         &self,
         params: FsCopyParams,
     ) -> Result<FsCopyResponse, JSONRPCErrorError> {
-        self.file_system
+        self.file_system()?
             .copy(
                 &params.source_path,
                 &params.destination_path,
@@ -179,6 +187,7 @@ impl FsRequestProcessor {
         connection_id: ConnectionId,
         params: FsWatchParams,
     ) -> Result<FsWatchResponse, JSONRPCErrorError> {
+        self.file_system()?;
         self.fs_watch_manager.watch(connection_id, params).await
     }
 
@@ -187,6 +196,7 @@ impl FsRequestProcessor {
         connection_id: ConnectionId,
         params: FsUnwatchParams,
     ) -> Result<FsUnwatchResponse, JSONRPCErrorError> {
+        self.file_system()?;
         self.fs_watch_manager.unwatch(connection_id, params).await
     }
 }

codex-rs/app-server/src/request_processors/process_exec_processor.rs

@@ -23,6 +23,7 @@ use codex_app_server_protocol::ServerNotification;
 use codex_core::exec::ExecExpiration;
 use codex_core::exec::ExecExpirationOutcome;
 use codex_core::exec::IO_DRAIN_TIMEOUT_MS;
+use codex_exec_server::EnvironmentManager;
 use codex_protocol::exec_output::bytes_to_string_smart;
 use codex_utils_absolute_path::AbsolutePathBuf;
 use codex_utils_pty::DEFAULT_OUTPUT_BYTES_CAP;
@@ -48,13 +49,18 @@ const OUTPUT_CHUNK_SIZE_HINT: usize = 64 * 1024;
 #[derive(Clone)]
 pub(crate) struct ProcessExecRequestProcessor {
     outgoing: Arc<OutgoingMessageSender>,
+    environment_manager: Arc<EnvironmentManager>,
     process_exec_manager: ProcessExecManager,
 }
 
 impl ProcessExecRequestProcessor {
-    pub(crate) fn new(outgoing: Arc<OutgoingMessageSender>) -> Self {
+    pub(crate) fn new(
+        outgoing: Arc<OutgoingMessageSender>,
+        environment_manager: Arc<EnvironmentManager>,
+    ) -> Self {
         Self {
             outgoing,
+            environment_manager,
             process_exec_manager: ProcessExecManager::default(),
         }
     }
@@ -64,6 +70,7 @@ impl ProcessExecRequestProcessor {
         request_id: ConnectionRequestId,
         params: ProcessSpawnParams,
     ) -> Result<(), JSONRPCErrorError> {
+        self.require_local_environment()?;
         let ProcessSpawnParams {
             command,
             process_handle,
@@ -173,6 +180,14 @@ impl ProcessExecRequestProcessor {
             .connection_closed(connection_id)
             .await;
     }
+
+    fn require_local_environment(&self) -> Result<(), JSONRPCErrorError> {
+        self.environment_manager
+            .try_local_environment()
+            .is_some()
+            .then_some(())
+            .ok_or_else(|| internal_error("local environment is not configured"))
+    }
 }
 
 #[derive(Clone, Default)]