epicsarchiver.retrieval.archiver_retrieval.async_archiver_retrieval

Module for an asynchronous version of archiver retriever.

Classes

AsyncArchiverRetrieval

Async retrieval client for the EPICS archiver appliance.

Functions

_format_date(→ str)

Module Contents

epicsarchiver.retrieval.archiver_retrieval.async_archiver_retrieval._format_date(at: datetime.datetime) → str[source]
class epicsarchiver.retrieval.archiver_retrieval.async_archiver_retrieval.AsyncArchiverRetrieval(hostname: str = 'localhost', port: int = 17665)[source]

Bases: epicsarchiver.common.async_service.ServiceClient

Async retrieval client for the EPICS archiver appliance.

Hold a session to the Archiver Appliance server to make retrieval requests.

Parameters:

  • hostname – EPICS Archiver Appliance hostname [default: localhost]

  • port – EPICS Archiver Appliance management port [default: 17665]

Examples:

from epicsarchiver.archiver.retrieval import AsyncArchiverRetrieval

async with AsyncArchiverRetrieval("archiver-01.tn.esss.lu.se") as archappl:
    events = await archappl.get_events(
        "my:pv",
        start=datetime.now(tz=UTC) - timedelta(seconds=1),
        end=datetime.utcnow(),
    )
hostname = 'localhost'[source]
port = 17665[source]
_data_url: str | None = None[source]
async data_url() → str[source]

EPICS Archiver Appliance data retrieval URL.

Raises:

ArchiverResponseError – Raises if archiver not available

Returns:

URL of retrieval engine

Return type:

str

async _get_data_raw(pv: str, start: datetime.datetime, end: datetime.datetime) → aiohttp.ClientResponse[source]

Fetch raw response from archiver data retrieval URL.

Parameters:
Returns:

Raw response from the archiver.

Return type:

ClientResponse

async get_events(pv: str, start: datetime.datetime, end: datetime.datetime, processor: epicsarchiver.retrieval.archiver_retrieval.processor.Processor | None = None) → list[epicsarchiver.retrieval.archive_event.ArchiveEvent][source]

Get a list of events from the archiver for specified pv and time period.

Parameters:

  • pv (str) – PV data requested for.

  • start (datetime.datetime) – Start time of the time period.

  • end (datetime.datetime) – End time fo the time period.

  • processor (Processor | None, optional) – Optional Preprocessor to use. Defaults to None.

Returns:

List of events in time period.

Return type:

list[ArchiveEvent]

async get_all_events(pvs: set[str], start: datetime.datetime, end: datetime.datetime, processor: epicsarchiver.retrieval.archiver_retrieval.processor.Processor | None = None) → dict[str, list[epicsarchiver.retrieval.archive_event.ArchiveEvent]][source]

Get a list of events for every pv requested.

Makes all the calls to the archiver asynchronously, so some maybe made in parallel.

Parameters:
Returns:

Dictionary of pvs (keys) and events (values).

Return type:

dict[str, list[ArchiveEvent]]