Module aws_lambda_powertools.utilities.data_classes.shared_functions

Functions

def base64_decode(value: str) ‑> str

Expand source code

def base64_decode(value: str) -> str:
    """
    Decodes a Base64-encoded string and returns the decoded value.

    Parameters
    ----------
    value: str
        The Base64-encoded string to decode.

    Returns
    -------
    str
        The decoded string value.
    """
    return base64.b64decode(value).decode("UTF-8")

Decodes a Base64-encoded string and returns the decoded value.

Parameters

value : str

The Base64-encoded string to decode.

Returns

str

The decoded string value.

def get_header_value(headers: dict[str, Any],
name: str,
default_value: str | None = None,
case_sensitive: bool = False) ‑> str | None

Expand source code

@deprecated(
    "`get_header_value` function is deprecated; Access headers directly using event.headers.get('HeaderName')",
    category=None,
)
def get_header_value(
    headers: dict[str, Any],
    name: str,
    default_value: str | None = None,
    case_sensitive: bool = False,
) -> str | None:
    """
    Get the value of a header by its name.
    Parameters
    ----------
    headers: Dict[str, str]
        The dictionary of headers.
    name: str
        The name of the header to retrieve.
    default_value: str, optional
        The default value to return if the header is not found. Default is None.
    case_sensitive: bool, optional
        Indicates whether the header name should be case-sensitive. Default is False.
    Returns
    -------
    str, optional
        The value of the header if found, otherwise the default value or None.
    """

    warnings.warn(
        "The `get_header_value` function is deprecated in V3 and the `case_sensitive` parameter "
        "no longer has any effect. This function will be removed in the next major version. "
        "Instead, access headers directly using event.headers.get('HeaderName'), which is case insensitive.",
        category=PowertoolsDeprecationWarning,
        stacklevel=2,
    )

    # If headers is NoneType, return default value
    if not headers:
        return default_value

    if case_sensitive:
        return headers.get(name, default_value)
    name_lower = name.lower()

    return next(
        # Iterate over the dict and do a case-insensitive key comparison
        (value for key, value in headers.items() if key.lower() == name_lower),
        # Default value is returned if no matches was found
        default_value,
    )

Get the value of a header by its name. Parameters

---

headers : Dict[str, str]

The dictionary of headers.

name : str

The name of the header to retrieve.

default_value : str, optional

The default value to return if the header is not found. Default is None.

case_sensitive : bool, optional

Indicates whether the header name should be case-sensitive. Default is False.

Returns

str, optional

The value of the header if found, otherwise the default value or None.

def get_multi_value_query_string_values(multi_value_query_string_parameters: dict[str, list[str]] | None,
name: str,
default_values: list[str] | None = None) ‑> list[str]

Expand source code

def get_multi_value_query_string_values(
    multi_value_query_string_parameters: dict[str, list[str]] | None,
    name: str,
    default_values: list[str] | None = None,
) -> list[str]:
    """
    Retrieves the values of a multi-value string parameters specified by the given name.
    Parameters
    ----------
    name: str
        The name of the query string parameter to retrieve.
    default_value: list[str], optional
        The default value to return if the parameter is not found. Defaults to None.
    Returns
    -------
    List[str]. optional
        The values of the query string parameter if found, or the default values if not found.
    """

    default = default_values or []
    params = multi_value_query_string_parameters or {}

    return params.get(name) or default

Retrieves the values of a multi-value string parameters specified by the given name. Parameters

---

name : str

The name of the query string parameter to retrieve.

default_value : list[str], optional

The default value to return if the parameter is not found. Defaults to None.

Returns

List[str]. optional

The values of the query string parameter if found, or the default values if not found.

def get_query_string_value(query_string_parameters: dict[str, str] | None,
name: str,
default_value: str | None = None) ‑> str | None

Expand source code

def get_query_string_value(
    query_string_parameters: dict[str, str] | None,
    name: str,
    default_value: str | None = None,
) -> str | None:
    """
    Retrieves the value of a query string parameter specified by the given name.
    Parameters
    ----------
    name: str
        The name of the query string parameter to retrieve.
    default_value: str, optional
        The default value to return if the parameter is not found. Defaults to None.
    Returns
    -------
    str. optional
        The value of the query string parameter if found, or the default value if not found.
    """
    params = query_string_parameters
    return default_value if params is None else params.get(name, default_value)

Retrieves the value of a query string parameter specified by the given name. Parameters

---

name : str

The name of the query string parameter to retrieve.

default_value : str, optional

The default value to return if the parameter is not found. Defaults to None.

Returns

str. optional

The value of the query string parameter if found, or the default value if not found.