Files
codex/codex-rs/app-server-client
rhan-oai 9e0c191c13 add turn items view to app-server turns (#21063)
## Why

`Turn.items` currently overloads an empty array to mean either that no
items exist or that the server intentionally did not load them for this
response. That ambiguity blocks future lazy-loading work where clients
need to distinguish unloaded, summary, and fully hydrated turn payloads.

## What changed

- add a new `TurnItemsView` enum with `notLoaded`, `summary`, and `full`
variants
- add required `itemsView` metadata to app-server `Turn` payloads
- mark reconstructed persisted history as `full` and live shell-style
turn payloads as `notLoaded`
- keep current `thread/turns/list` behavior unchanged and document that
it still returns `full` turns today
- regenerate the JSON and TypeScript protocol fixtures

## Verification

- `just write-app-server-schema`
- `cargo test -p codex-app-server-protocol`
- `cargo test -p codex-app-server thread_read_can_include_turns`
- `cargo test -p codex-app-server
thread_turns_list_can_page_backward_and_forward`
- `cargo test -p codex-app-server
thread_resume_rejects_history_when_thread_is_running`
- `just fix -p codex-app-server-protocol`
- `just fix -p codex-app-server`
- `just fmt`
2026-05-05 19:17:16 +00:00
..

codex-app-server-client

Shared in-process app-server client used by conversational CLI surfaces:

  • codex-exec
  • codex-tui

Purpose

This crate centralizes startup and lifecycle management for an in-process codex-app-server runtime, so CLI clients do not need to duplicate:

  • app-server bootstrap and initialize handshake
  • in-memory request/event transport wiring
  • lifecycle orchestration around caller-provided startup identity
  • graceful shutdown behavior

Startup identity

Callers pass both the app-server SessionSource and the initialize client_info.name explicitly when starting the facade.

That keeps thread metadata (for example in thread/list and thread/read) aligned with the originating runtime without baking TUI/exec-specific policy into the shared client layer.

Transport model

The in-process path uses typed channels:

  • client -> server: ClientRequest / ClientNotification
  • server -> client: InProcessServerEvent
    • ServerRequest
    • ServerNotification
    • LegacyNotification

JSON serialization is still used at external transport boundaries (stdio/websocket), but the in-process hot path is typed.

Typed requests still receive app-server responses through the JSON-RPC result envelope internally. That is intentional: the in-process path is meant to preserve app-server semantics while removing the process boundary, not to introduce a second response contract.

Bootstrap behavior

The client facade starts an already-initialized in-process runtime, but thread bootstrap still follows normal app-server flow:

  • caller sends thread/start or thread/resume
  • app-server returns the immediate typed response
  • richer session metadata may arrive later as a SessionConfigured legacy event

Surfaces such as TUI and exec may therefore need a short bootstrap phase where they reconcile startup response data with later events.

Backpressure and shutdown

  • Queues are bounded and use DEFAULT_IN_PROCESS_CHANNEL_CAPACITY by default.
  • Full queues return explicit overload behavior instead of unbounded growth.
  • shutdown() performs a bounded graceful shutdown and then aborts if timeout is exceeded.

If the client falls behind on event consumption, the worker emits InProcessServerEvent::Lagged and may reject pending server requests so approval flows do not hang indefinitely behind a saturated queue.