| # DaemonManager |
| |
| `DaemonManager` is a lightweight, client-side library responsible for |
| spawning, connecting to, and managing the lifecycle of the background |
| `zxdb-daemon` process. |
| |
| ## Core Features |
| |
| - **Subprocess Lifecycle Management**: Spawns `zxdb-daemon` using a |
| platform-specific command-line wrapper (`FxCmd`). |
| - **Startup Synchronization**: Block-waits for daemon readiness via an |
| inherited pipe file descriptor (`--ready-fd`), guarding against premature |
| crashes and startup timeouts. |
| - **Unix Domain Socket (UDS) Connectivity**: Connects to the daemon over a |
| local socket (default: `/tmp/fx-debug-daemon.sock`) and executes DAP session |
| handshake verifications (`HelloRequest`/`StartRequest`). |
| - **Fault Tolerance & Cleanup**: Automatically unlinks stale sockets on |
| startup, prevents double-running daemon processes, and guarantees graceful |
| (`SIGTERM`) or forceful (`SIGKILL`) process group cleanup on failures. |
| |
| ## Directory Layout |
| |
| - [manager.py](manager.py): Core implementation of the `DaemonManager` class, |
| lifecycle exceptions, and helper processes. |
| - [tests/test_manager.py](tests/test_manager.py): Thorough asynchronous unit |
| and process-group integration tests. |
| - [BUILD.gn](BUILD.gn): Declares the python target library and its |
| test target. |
| |
| ## Usage |
| |
| Downstream tools (such as `fx test`) import `DaemonManager` directly to |
| coordinate background debugger attachments: |
| |
| ```python |
| from daemon_manager import DaemonManager |
| |
| manager = DaemonManager(port=15678, connect_to_existing=True) |
| process = await manager.start() |
| ``` |
