// (case-sensitive) and will fail otherwise.
// Further, some clients require that the ETag value is a double-quoted
// string. Therefore, this package provides dedicated functions for
// adding and extracting the ETag to/from HTTP headers.
package etag

import (
	"bytes"
	"crypto/hmac"
	"crypto/md5"
	"encoding/base64"
	"encoding/hex"
	"errors"
	"fmt"
	"net/http"
	"strconv"
	"strings"

## Simple usage { #simple-usage }

If you look at it, *path operation functions* are declared to be used whenever a *path* and *operation* matches, and then **FastAPI** takes care of calling the function with the correct parameters, extracting the data from the request.

Actually, all (or most) of the web frameworks work in this same way.

You never call those functions directly. They are called by your framework (in this case, **FastAPI**).

    /**
     * Extracts keywords from the given query string based on the specified fields.
     *
     * @param q the query string to parse and extract keywords from
     * @param fields the fields to consider when extracting keywords
     * @return a list of unique keywords extracted from the query string
     */
    public static List<String> getKeywords(final String q, final String[] fields) {

   * <p>A "coerced" IPv4 address is equivalent to itself.
   *
   * <p>NOTE: This method is failsafe for security purposes: ALL IPv6 addresses (except localhost
   * (::1)) are hashed to avoid the security risk associated with extracting an embedded IPv4
   * address that might permit elevated privileges.
   *
   * @param ip {@link InetAddress} to "coerce"
   * @return {@link Inet4Address} represented "coerced" address
   * @since 7.0
   */

   * <p>A "coerced" IPv4 address is equivalent to itself.
   *
   * <p>NOTE: This method is failsafe for security purposes: ALL IPv6 addresses (except localhost
   * (::1)) are hashed to avoid the security risk associated with extracting an embedded IPv4
   * address that might permit elevated privileges.
   *
   * @param ip {@link InetAddress} to "coerce"
   * @return {@link Inet4Address} represented "coerced" address
   * @since 7.0
   */

                else:
                    yield {**(maybe_nested_state or {}), **(maybe_original_state or {})}

    return merged_lifespan  # type: ignore[return-value]


# Cache for endpoint context to avoid re-extracting on every request
_endpoint_context_cache: dict[int, EndpointContext] = {}


def _extract_endpoint_context(func: Any) -> EndpointContext:
    """Extract endpoint context with caching to avoid repeated file I/O."""

- Expose a `NewUnstructuredExtractor` from apply configurations `meta/v1` package that enables extracting objects into unstructured apply configurations. ([#103564](https://github.com/kubernetes/kubernetes/pull/103564), [@kevindelgado](https://github.com/kevindelgado))