Files
llmx/codex-rs/app-server/tests/suite/send_message.rs
Michael Bolin d9dbf48828 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`.
2025-09-30 07:06:18 +00:00

187 lines
6.7 KiB
Rust

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
"#
),
)
}