Function _proxy

dashboard/hermes-wrapper/plugin_api.py:411–450

(method: str, upstream_path: str, request: Request, body: bytes | None)

def _proxy(method: str, upstream_path: str, request: Request, body: bytes | None) -> JSONResponse:
    # Connection-level failures (reset/refused) on GETs are retried once
    # after re-resolving the upstream: _upstream_base reaps a dead child and
    # respawns it (then waits for readiness), so a mid-flight engine death
    # heals transparently instead of surfacing a one-off 502. POSTs are never
    # retried — curation applies must not run twice.
    attempts = 2 if method == "GET" else 1
    last_exc: Exception | None = None
    for attempt in range(attempts):
        base = _upstream_base()
        query = request.url.query
        url = f"{base}{upstream_path}" + (f"?{query}" if query else "")
        parsed = urllib.parse.urlparse(url)
        if parsed.scheme not in ("http", "https"):
            raise HTTPException(status_code=502, detail="invalid upstream URL scheme")
        req = urllib.request.Request(
            url,
            data=body if method == "POST" else None,
            method=method,
            headers={"Content-Type": "application/json"} if body else {},
        )
        try:
            with urllib.request.urlopen(req, timeout=_PROXY_TIMEOUT_SECONDS) as resp:  # noqa: S310 — loopback/configured upstream only
                payload = json.loads(resp.read().decode("utf-8"))
                return JSONResponse(payload, status_code=resp.status)
        except urllib.error.HTTPError as exc:
            try:
                payload = json.loads(exc.read().decode("utf-8"))
            except Exception:
                payload = {"detail": str(exc)}
            return JSONResponse(payload, status_code=exc.code)
        except Exception as exc:
            last_exc = exc
            if attempt + 1 < attempts:
                logger.warning(
                    "tracedecay dashboard proxy request failed (%s); retrying once", exc
                )
                continue
            logger.exception("tracedecay dashboard proxy request failed")
    raise HTTPException(status_code=502, detail=f"tracedecay dashboard unreachable: {last_exc}")


class _DummyRequest: