fix: separate codex mcp into codex mcp-server and codex app-server (#4471)
This is a very large PR with some non-backwards-compatible changes. Historically, `codex mcp` (or `codex mcp serve`) started a JSON-RPC-ish server that had two overlapping responsibilities: - Running an MCP server, providing some basic tool calls. - Running the app server used to power experiences such as the VS Code extension. This PR aims to separate these into distinct concepts: - `codex mcp-server` for the MCP server - `codex app-server` for the "application server" Note `codex mcp` still exists because it already has its own subcommands for MCP management (`list`, `add`, etc.) The MCP logic continues to live in `codex-rs/mcp-server` whereas the refactored app server logic is in the new `codex-rs/app-server` folder. Note that most of the existing integration tests in `codex-rs/mcp-server/tests/suite` were actually for the app server, so all the tests have been moved with the exception of `codex-rs/mcp-server/tests/suite/mod.rs`. Because this is already a large diff, I tried not to change more than I had to, so `codex-rs/app-server/tests/common/mcp_process.rs` still uses the name `McpProcess` for now, but I will do some mechanical renamings to things like `AppServer` in subsequent PRs. While `mcp-server` and `app-server` share some overlapping functionality (like reading streams of JSONL and dispatching based on message types) and some differences (completely different message types), I ended up doing a bit of copypasta between the two crates, as both have somewhat similar `message_processor.rs` and `outgoing_message.rs` files for now, though I expect them to diverge more in the near future. One material change is that of the initialize handshake for `codex app-server`, as we no longer use the MCP types for that handshake. Instead, we update `codex-rs/protocol/src/mcp_protocol.rs` to add an `Initialize` variant to `ClientRequest`, which takes the `ClientInfo` object we need to update the `USER_AGENT_SUFFIX` in `codex-rs/app-server/src/message_processor.rs`. One other material change is in `codex-rs/app-server/src/codex_message_processor.rs` where I eliminated a use of the `send_event_as_notification()` method I am generally trying to deprecate (because it blindly maps an `EventMsg` into a `JSONNotification`) in favor of `send_server_notification()`, which takes a `ServerNotification`, as that is intended to be a custom enum of all notification types supported by the app server. So to make this update, I had to introduce a new variant of `ServerNotification`, `SessionConfigured`, which is a non-backwards compatible change with the old `codex mcp`, and clients will have to be updated after the next release that contains this PR. Note that `codex-rs/app-server/tests/suite/list_resume.rs` also had to be update to reflect this change. I introduced `codex-rs/utils/json-to-toml/src/lib.rs` as a small utility crate to avoid some of the copying between `mcp-server` and `app-server`.
This commit is contained in:
Michael Bolin
GitHub
186
codex-rs/app-server/tests/suite/send_message.rs
Normal file
186
codex-rs/app-server/tests/suite/send_message.rs
Normal file
@@ -0,0 +1,186 @@
|
||||
use std::path::Path;
|
||||
|
||||
use app_test_support::McpProcess;
|
||||
use app_test_support::create_final_assistant_message_sse_response;
|
||||
use app_test_support::create_mock_chat_completions_server;
|
||||
use app_test_support::to_response;
|
||||
use codex_protocol::mcp_protocol::AddConversationListenerParams;
|
||||
use codex_protocol::mcp_protocol::AddConversationSubscriptionResponse;
|
||||
use codex_protocol::mcp_protocol::ConversationId;
|
||||
use codex_protocol::mcp_protocol::InputItem;
|
||||
use codex_protocol::mcp_protocol::NewConversationParams;
|
||||
use codex_protocol::mcp_protocol::NewConversationResponse;
|
||||
use codex_protocol::mcp_protocol::SendUserMessageParams;
|
||||
use codex_protocol::mcp_protocol::SendUserMessageResponse;
|
||||
use mcp_types::JSONRPCNotification;
|
||||
use mcp_types::JSONRPCResponse;
|
||||
use mcp_types::RequestId;
|
||||
use pretty_assertions::assert_eq;
|
||||
use tempfile::TempDir;
|
||||
use tokio::time::timeout;
|
||||
|
||||
const DEFAULT_READ_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(10);
|
||||
|
||||
#[tokio::test]
|
||||
async fn test_send_message_success() {
|
||||
// Spin up a mock completions server that immediately ends the Codex turn.
|
||||
// Two Codex turns hit the mock model (session start + send-user-message). Provide two SSE responses.
|
||||
let responses = vec![
|
||||
create_final_assistant_message_sse_response("Done").expect("build mock assistant message"),
|
||||
create_final_assistant_message_sse_response("Done").expect("build mock assistant message"),
|
||||
];
|
||||
let server = create_mock_chat_completions_server(responses).await;
|
||||
|
||||
// Create a temporary Codex home with config pointing at the mock server.
|
||||
let codex_home = TempDir::new().expect("create temp dir");
|
||||
create_config_toml(codex_home.path(), &server.uri()).expect("write config.toml");
|
||||
|
||||
// Start MCP server process and initialize.
|
||||
let mut mcp = McpProcess::new(codex_home.path())
|
||||
.await
|
||||
.expect("spawn mcp process");
|
||||
timeout(DEFAULT_READ_TIMEOUT, mcp.initialize())
|
||||
.await
|
||||
.expect("init timed out")
|
||||
.expect("init failed");
|
||||
|
||||
// Start a conversation using the new wire API.
|
||||
let new_conv_id = mcp
|
||||
.send_new_conversation_request(NewConversationParams::default())
|
||||
.await
|
||||
.expect("send newConversation");
|
||||
let new_conv_resp: JSONRPCResponse = timeout(
|
||||
DEFAULT_READ_TIMEOUT,
|
||||
mcp.read_stream_until_response_message(RequestId::Integer(new_conv_id)),
|
||||
)
|
||||
.await
|
||||
.expect("newConversation timeout")
|
||||
.expect("newConversation resp");
|
||||
let NewConversationResponse {
|
||||
conversation_id, ..
|
||||
} = to_response::<_>(new_conv_resp).expect("deserialize newConversation response");
|
||||
|
||||
// 2) addConversationListener
|
||||
let add_listener_id = mcp
|
||||
.send_add_conversation_listener_request(AddConversationListenerParams { conversation_id })
|
||||
.await
|
||||
.expect("send addConversationListener");
|
||||
let add_listener_resp: JSONRPCResponse = timeout(
|
||||
DEFAULT_READ_TIMEOUT,
|
||||
mcp.read_stream_until_response_message(RequestId::Integer(add_listener_id)),
|
||||
)
|
||||
.await
|
||||
.expect("addConversationListener timeout")
|
||||
.expect("addConversationListener resp");
|
||||
let AddConversationSubscriptionResponse { subscription_id: _ } =
|
||||
to_response::<_>(add_listener_resp).expect("deserialize addConversationListener response");
|
||||
|
||||
// Now exercise sendUserMessage twice.
|
||||
send_message("Hello", conversation_id, &mut mcp).await;
|
||||
send_message("Hello again", conversation_id, &mut mcp).await;
|
||||
}
|
||||
|
||||
#[expect(clippy::expect_used)]
|
||||
async fn send_message(message: &str, conversation_id: ConversationId, mcp: &mut McpProcess) {
|
||||
// Now exercise sendUserMessage.
|
||||
let send_id = mcp
|
||||
.send_send_user_message_request(SendUserMessageParams {
|
||||
conversation_id,
|
||||
items: vec![InputItem::Text {
|
||||
text: message.to_string(),
|
||||
}],
|
||||
})
|
||||
.await
|
||||
.expect("send sendUserMessage");
|
||||
|
||||
let response: JSONRPCResponse = timeout(
|
||||
DEFAULT_READ_TIMEOUT,
|
||||
mcp.read_stream_until_response_message(RequestId::Integer(send_id)),
|
||||
)
|
||||
.await
|
||||
.expect("sendUserMessage response timeout")
|
||||
.expect("sendUserMessage response error");
|
||||
|
||||
let _ok: SendUserMessageResponse = to_response::<SendUserMessageResponse>(response)
|
||||
.expect("deserialize sendUserMessage response");
|
||||
|
||||
// Verify the task_finished notification is received.
|
||||
// Note this also ensures that the final request to the server was made.
|
||||
let task_finished_notification: JSONRPCNotification = timeout(
|
||||
DEFAULT_READ_TIMEOUT,
|
||||
mcp.read_stream_until_notification_message("codex/event/task_complete"),
|
||||
)
|
||||
.await
|
||||
.expect("task_finished_notification timeout")
|
||||
.expect("task_finished_notification resp");
|
||||
let serde_json::Value::Object(map) = task_finished_notification
|
||||
.params
|
||||
.expect("notification should have params")
|
||||
else {
|
||||
panic!("task_finished_notification should have params");
|
||||
};
|
||||
assert_eq!(
|
||||
map.get("conversationId")
|
||||
.expect("should have conversationId"),
|
||||
&serde_json::Value::String(conversation_id.to_string())
|
||||
);
|
||||
}
|
||||
|
||||
#[tokio::test]
|
||||
async fn test_send_message_session_not_found() {
|
||||
// Start MCP without creating a Codex session
|
||||
let codex_home = TempDir::new().expect("tempdir");
|
||||
let mut mcp = McpProcess::new(codex_home.path()).await.expect("spawn");
|
||||
timeout(DEFAULT_READ_TIMEOUT, mcp.initialize())
|
||||
.await
|
||||
.expect("timeout")
|
||||
.expect("init");
|
||||
|
||||
let unknown = ConversationId::new();
|
||||
let req_id = mcp
|
||||
.send_send_user_message_request(SendUserMessageParams {
|
||||
conversation_id: unknown,
|
||||
items: vec![InputItem::Text {
|
||||
text: "ping".to_string(),
|
||||
}],
|
||||
})
|
||||
.await
|
||||
.expect("send sendUserMessage");
|
||||
|
||||
// Expect an error response for unknown conversation.
|
||||
let err = timeout(
|
||||
DEFAULT_READ_TIMEOUT,
|
||||
mcp.read_stream_until_error_message(RequestId::Integer(req_id)),
|
||||
)
|
||||
.await
|
||||
.expect("timeout")
|
||||
.expect("error");
|
||||
assert_eq!(err.id, RequestId::Integer(req_id));
|
||||
}
|
||||
|
||||
// ---------------------------------------------------------------------------
|
||||
// Helpers
|
||||
// ---------------------------------------------------------------------------
|
||||
|
||||
fn create_config_toml(codex_home: &Path, server_uri: &str) -> std::io::Result<()> {
|
||||
let config_toml = codex_home.join("config.toml");
|
||||
std::fs::write(
|
||||
config_toml,
|
||||
format!(
|
||||
r#"
|
||||
model = "mock-model"
|
||||
approval_policy = "never"
|
||||
sandbox_mode = "danger-full-access"
|
||||
|
||||
model_provider = "mock_provider"
|
||||
|
||||
[model_providers.mock_provider]
|
||||
name = "Mock provider for test"
|
||||
base_url = "{server_uri}/v1"
|
||||
wire_api = "chat"
|
||||
request_max_retries = 0
|
||||
stream_max_retries = 0
|
||||
"#
|
||||
),
|
||||
)
|
||||
}
|
||||
Reference in New Issue
Block a user