// The supported values are: "TCP", "UDP", "SCTP"
  optional string protocol = 2;

  // Error is to record the problem with the service port
  // The format of the error shall comply with the following rules:
  // - built-in error values shall be specified in this file and those shall use
  //   CamelCase names
  // - cloud provider specific error values must have names that comply with the

    /**
     * Sets the header named [name] to [value]. If this request already has any headers
     * with that name, they are all replaced.
     */
    open fun header(
      name: String,
      value: String,
    ) = commonHeader(name, value)

    /**
     * Adds a header with [name] and [value]. Prefer this method for multiply-valued
     * headers like "Cookie".
     *

  //  2. Permitted subjects: and behavior when a disallowed subject is requested.
  //  3. Required, permitted, or forbidden x509 extensions in the request (including whether subjectAltNames are allowed, which types, restrictions on allowed values) and behavior when a disallowed extension is requested.
  //  4. Required, permitted, or forbidden key usages / extended key usages.

    ```Python hl_lines="80-83"
    {!> ../../../docs_src/security/tutorial003.py!}
    ```

#### About `**user_dict`

`UserInDB(**user_dict)` means:

*Pass the keys and values of the `user_dict` directly as key-value arguments, equivalent to:*

```Python
UserInDB(
    username = user_dict["username"],
    email = user_dict["email"],
    full_name = user_dict["full_name"],

  // The maximum number of DaemonSet pods that can be unavailable during the
  // update. Value can be an absolute number (ex: 5) or a percentage of total
  // number of DaemonSet pods at the start of the update (ex: 10%). Absolute
  // number is calculated from percentage by rounding up.
  // This cannot be 0 if MaxSurge is 0
  // Default value is 1.
  // Example: when this is set to 30%, at most 30% of the total number of nodes

So:

```Python
q: Union[str, None] = Query(default=None)
```

...makes the parameter optional, with a default value of `None`, the same as:

```Python

    ): Headers {
      val result = Headers.Builder()

      for (index in 0 until cachedHeaders.size) {
        val fieldName = cachedHeaders.name(index)
        val value = cachedHeaders.value(index)
        if ("Warning".equals(fieldName, ignoreCase = true) && value.startsWith("1")) {
          // Drop 100-level freshness warnings.
          continue
        }
        if (isContentSpecificHeader(fieldName) ||

        this.name = name
      }

    fun value(value: String) =
      apply {
        require(value.trim() == value) { "value is not trimmed" }
        this.value = value
      }

    fun expiresAt(expiresAt: Long) =
      apply {
        var expiresAt = expiresAt
        if (expiresAt <= 0L) expiresAt = Long.MIN_VALUE
        if (expiresAt > MAX_DATE) expiresAt = MAX_DATE

        .build(),
    )
    val webSocket = newWebSocket()
    clientListener.assertFailure(
      101,
      null,
      ProtocolException::class.java,
      "Expected 'Connection' header value 'Upgrade' but was 'null'",
    )
    webSocket.cancel()
  }

  @Test
  @Throws(IOException::class)
  fun wrongConnectionHeader() {
    webServer.enqueue(
      MockResponse.Builder()

            "loc": [
                "path",
                "item_id"
            ],
            "msg": "value is not a valid integer",
            "type": "type_error.integer"
        }
    ]
}
```

eine Textversion:

```
1 validation error
path -> item_id
  value is not a valid integer (type=type_error.integer)
```

#### `RequestValidationError` vs. `ValidationError`