Tables, errors and discovery¶

ArrowTable ¶

ArrowTable(columns: dict[str, tuple[list, Any]])

A table of query results, ready to load into any Arrow-aware dataframe library.

It implements the Arrow PyCapsule interface, so it can be passed straight to polars, pandas, pyarrow, DuckDB and others without signalk-cli depending on any of them:

Examples:

import polars as pl
df = pl.DataFrame(table)
import pandas as pd
df = pd.DataFrame.from_arrow(table)  # pandas >= 3.0
import pyarrow as pa
t = pa.table(table)

num_rows `property` ¶

num_rows: int

column_names `property` ¶

column_names: list[str]

to_pydict ¶

to_pydict() -> dict[str, list]

Return the columns as plain Python lists (timestamps as epoch microseconds).

SignalKError ¶

SignalKError(
    message: str, *, status_code: int | None = None
)

Bases: Exception

A request to a SignalK server failed.

Attributes:

status_code –

HTTP status of the failed response, or None if the server couldn’t be reached.

from_request `classmethod` ¶

from_request(exc: RequestException) -> SignalKError

Wrap a niquests exception, using the server’s error message if it sent one.

discover_host ¶

discover_host(timeout: float = 5.0) -> str | None

Browse mDNS for a SignalK server and return its base URL, or None.