ruvnet/RuView · error · ImportError

RuViewMqttClient requires the `paho-mqtt` package. Install w

Error message

RuViewMqttClient requires the `paho-mqtt` package. Install with `pip install "wifi-densepose[client]"` to enable the client extras.

What it means

RuViewMqttClient.__init__ raises ImportError when the optional paho-mqtt dependency is absent. The module-level import is guarded via _PAHO_AVAILABLE so the rest of wifi_densepose.client stays importable; the failure is deferred to construction time with instructions to install the `client` extra.

Source

Thrown at python/wifi_densepose/client/mqtt.py:79

      tests run in parallel against the same broker).
    - Subscription wildcards (`+`, `#`) are supported by paho's
      built-in matcher; we route by exact pattern match against the
      registered handler.
    """

    def __init__(
        self,
        *,
        broker_host: str = "localhost",
        broker_port: int = 1883,
        client_id: Optional[str] = None,
        username: Optional[str] = None,
        password: Optional[str] = None,
        keepalive: int = 60,
        tls: bool = False,
    ) -> None:
        if not _PAHO_AVAILABLE:
            raise ImportError(
                "RuViewMqttClient requires the `paho-mqtt` package. Install with "
                "`pip install \"wifi-densepose[client]\"` to enable the client extras."
            )
        self.broker_host = broker_host
        self.broker_port = broker_port
        self.keepalive = keepalive
        self._client_id = client_id or f"wifi-densepose-client-{uuid.uuid4().hex[:12]}"
        self._handlers: dict[str, MessageHandler] = {}
        self._handlers_lock = threading.Lock()
        self._client = mqtt.Client(
            callback_api_version=CallbackAPIVersion.VERSION2,
            client_id=self._client_id,
            clean_session=True,
        )
        if username is not None:
            self._client.username_pw_set(username, password)
        if tls:
            self._client.tls_set()

View on GitHub (pinned to 4685618388)

Solutions

Install the extra: pip install "wifi-densepose[client]"
Or install the dependency directly: pip install paho-mqtt (v2 required — the client uses CallbackAPIVersion.VERSION2)
Add the extra to pyproject/requirements so lockfiles and deploy environments carry it

Example fix

# before
pip install wifi-densepose

# after
pip install "wifi-densepose[client]"

Defensive patterns

Strategy: validation

Validate before calling

import importlib.util

if importlib.util.find_spec("paho") is None:
    raise SystemExit(
        "paho-mqtt missing; run: pip install 'wifi-densepose[client]'"
    )
from wifi_densepose.client import RuViewMqttClient
client = RuViewMqttClient(broker_host="localhost")

Try / catch

try:
    client = RuViewMqttClient(broker_host=host)
except ImportError as e:
    log.warning("MQTT telemetry disabled: %s", e)
    client = None  # degrade to a no-op sink instead of crashing

Prevention

Depend on wifi-densepose[client], not the bare package, in deployable environments
Add a CI test that constructs RuViewMqttClient to catch missing extras
Audit Dockerfiles for bare pip installs of the package

When it happens

Trigger: Constructing `RuViewMqttClient(broker_host=...)` in an environment where only the base wifi-densepose wheel is installed (no `[client]` extra) and paho-mqtt is missing.

Common situations: Minimal Docker images; prod installs trimmed to `pip install wifi-densepose`; dependency resolvers or lockfiles that drop extras.

Related errors

AI-assisted analysis of ruvnet/RuView@4685618388 (2026-08-16). Data as JSON: /api/errors/b4d859642cb7b69a. Report an issue: GitHub.