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Overview API

Overview checks whether a Science Platform Server reports itself as available. It inherits HTTPClient and uses the selected or explicitly supplied credentials.

from canfar.overview import Overview

with Overview() as overview:
    if overview.availability():
        print("Science Platform Server is available")

availability() returns True only when the VOSI availability response says the server is available. Empty or malformed availability data returns False and is logged.

Bases: HTTPClient

Overview of the CANFAR Server.

This class is a subclass of the HTTPClient class and inherits its attributes and methods.

Examples:

>>> from canfar.overview import Overview
>>> overview = Overview()
>>> overview.availability()
True
Source code in canfar/overview.py 
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class Overview(HTTPClient):
    """Overview of the CANFAR Server.

    This class is a subclass of the `HTTPClient` class and inherits its
    attributes and methods.

    Examples:
        >>> from canfar.overview import Overview
        >>> overview = Overview()
        >>> overview.availability()
        True
    """

    @model_validator(mode="after")
    def _update_base_url(self) -> Self:
        """Update base URL for the server.

        Returns:
            Self: The current object.
        """
        url: str = str(self.client.base_url)
        base: str = url.split("/v", maxsplit=1)[0]
        # The overview endpoint is not versioned, so need to remove it
        self.client.base_url = URL(base)
        self.asynclient.base_url = URL(base)
        return self

    def availability(self) -> bool:
        """Check if the server backend is available.

        Returns:
            bool: True if the server is available, False otherwise.
        """
        response: Response = self.client.get("availability")
        data: str = response.text
        if not data:
            log.error("No data returned from availability endpoint.")
            return False
        root = ElementTree.fromstring(data)
        available = root.find(
            ".//{http://www.ivoa.net/xml/VOSIAvailability/v1.0}available",
        )
        availaibility: str | None = available.text if available is not None else None

        note = root.find(
            ".//{http://www.ivoa.net/xml/VOSIAvailability/v1.0}note",
        )
        notify: str | None = note.text if note is not None else None
        if availaibility is None:
            log.error("No availability information found in the response.")
            return False
        log.info(notify or "No additional information provided.")
        return availaibility == "true"

availability 

availability()

Check if the server backend is available.

RETURNS DESCRIPTION
bool

True if the server is available, False otherwise.

TYPE: bool

Source code in canfar/overview.py 
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def availability(self) -> bool:
    """Check if the server backend is available.

    Returns:
        bool: True if the server is available, False otherwise.
    """
    response: Response = self.client.get("availability")
    data: str = response.text
    if not data:
        log.error("No data returned from availability endpoint.")
        return False
    root = ElementTree.fromstring(data)
    available = root.find(
        ".//{http://www.ivoa.net/xml/VOSIAvailability/v1.0}available",
    )
    availaibility: str | None = available.text if available is not None else None

    note = root.find(
        ".//{http://www.ivoa.net/xml/VOSIAvailability/v1.0}note",
    )
    notify: str | None = note.text if note is not None else None
    if availaibility is None:
        log.error("No availability information found in the response.")
        return False
    log.info(notify or "No additional information provided.")
    return availaibility == "true"