Local log server

Receives logs from the demo application over HTTP and appends them to a local JSONL file. It does nothing else — reading the logs back is the job of @craft-ts/log-mcp.

npm run logs:server

Endpoints

| Method | Path | Description | | -------- | --------- | -------------------------------------------------- | | POST | /logs | Ingest a batch. Answers 202 {"accepted": n}. | | DELETE | /logs | Delete the active and rotated files. | | GET | /health | Target file and its current size. |

POST /logs accepts three body shapes: a { clientId, entries: [...] } envelope (what the demo sends), a bare array of entries, or a single entry. Entries missing a known level are dropped individually — one bad entry never rejects the whole batch. CORS is wide open: this is a loopback dev tool.

Storage

One JSON object per line in .logs/app.jsonl, oldest first. Each stored entry keeps the browser timestamp and adds a server-side receivedAt plus an incrementing seq. Once the active file exceeds LOG_SERVER_MAX_FILE_SIZE it is rotated to app.jsonl.1, existing rotated files shift down one slot, and anything past LOG_SERVER_MAX_FILES is dropped.

Environment

| Variable | Default | Description | | -------------------------- | ----------- | --------------------------------- | | LOG_SERVER_HOST | 127.0.0.1 | Listen address | | LOG_SERVER_PORT | 4319 | Listen port | | LOG_SERVER_DIR | ./.logs | Storage directory | | LOG_SERVER_MAX_FILE_SIZE | 5242880 | Rotation threshold, in bytes | | LOG_SERVER_MAX_FILES | 5 | Rotated files kept | | LOG_SERVER_QUIET | unset | Set to 1 to silence ingest echo |

LOG_SERVER_DIR and LOG_SERVER_MAX_FILES must match what the MCP server uses, otherwise it reads a different set of files.