* specific length.
   *
   * <p>For example, if you need 1024-bit hash codes, you could join two {@link Hashing#sha512} hash
   * functions together: {@code Hashing.concatenating(Hashing.sha512(), Hashing.sha512())}.
   *
   * @since 19.0
   */
  public static HashFunction concatenating(
      HashFunction first, HashFunction second, HashFunction... rest) {

}

// Replacer replacer interface like strings.Replacer
type Replacer interface {
	Replace(name string) string
}

var _ Namer = (*NamingStrategy)(nil)

// NamingStrategy tables, columns naming strategy
type NamingStrategy struct {
	TablePrefix         string
	SingularTable       bool
	NameReplacer        Replacer
	NoLowerCase         bool
	IdentifierMaxLength int
}

mohammad ali <******@****.***> 1685412048 -0700

    assertEquals("Hashing.md5()", Hashing.md5().toString());
    assertEquals("Hashing.sha1()", Hashing.sha1().toString());
    assertEquals("Hashing.sha256()", Hashing.sha256().toString());
    assertEquals("Hashing.sha512()", Hashing.sha512().toString());
  }

  private static void assertMessageDigestHashing(byte[] input, String algorithmName) {
    try {
      MessageDigest digest = MessageDigest.getInstance(algorithmName);

    assertEquals(
        "Hashing.hmacMd5(Key[algorithm=HmacMD5, format=RAW])", Hashing.hmacMd5(MD5_KEY).toString());
    assertEquals(
        "Hashing.hmacMd5(Key[algorithm=HmacMD5, format=RAW])", Hashing.hmacMd5(keyData).toString());

    assertEquals(
        "Hashing.hmacSha1(Key[algorithm=HmacSHA1, format=RAW])",
        Hashing.hmacSha1(SHA1_KEY).toString());
    assertEquals(

    assertEquals(
        "Hashing.hmacMd5(Key[algorithm=HmacMD5, format=RAW])", Hashing.hmacMd5(MD5_KEY).toString());
    assertEquals(
        "Hashing.hmacMd5(Key[algorithm=HmacMD5, format=RAW])", Hashing.hmacMd5(keyData).toString());

    assertEquals(
        "Hashing.hmacSha1(Key[algorithm=HmacSHA1, format=RAW])",
        Hashing.hmacSha1(SHA1_KEY).toString());
    assertEquals(

Unlike many projects on GitHub, the Go project does not use its bug tracker for general discussion or asking questions.
We only use our bug tracker for tracking bugs and tracking proposals going through the [Proposal Process](https://go.dev/s/proposal-process).

For asking questions, see:

* [The golang-nuts mailing list](https://groups.google.com/d/forum/golang-nuts)

* [The Go Forum](https://forum.golangbridge.org/), a web-based forum

不过，仍可以验证、转换与注释（使用 Pydantic 模型的请求体等）其它正常声明的参数。

但在某些特定情况下，还是需要提取 `Request` 对象。

## 直接使用 `Request` 对象

假设要在*路径操作函数*中获取客户端 IP 地址和主机。

此时，需要直接访问请求。

```Python hl_lines="1  7-8"
{!../../../docs_src/using_request_directly/tutorial001.py!}
```

把*路径操作函数*的参数类型声明为 `Request`，**FastAPI** 就能把 `Request` 传递到参数里。

!!! tip "提示"

    注意，本例除了声明请求参数之外，还声明了路径参数。

    因此，能够提取、验证路径参数、并转换为指定类型，还可以用 OpenAPI 注释。

                                  description: The Maglev load balancer implements
                                    consistent hashing to backend hosts.
                                  properties:
                                    tableSize:
                                      description: The table size for Maglev hashing.
                                      type: integer
                                  type: object

    }

    if (hashTableKToV.length < minCapacity) {
      int newTableSize = Hashing.closedTableSize(minCapacity, 1.0);
      hashTableKToV = createFilledWithAbsent(newTableSize);
      hashTableVToK = createFilledWithAbsent(newTableSize);

      for (int entryToRehash = 0; entryToRehash < size; entryToRehash++) {
        int keyHash = Hashing.smearedHash(keys[entryToRehash]);
        int keyBucket = bucket(keyHash);