```Python
from fastapi import FastAPI
from unicorn import UnicornMiddleware

app = FastAPI()

app.add_middleware(UnicornMiddleware, some_config="rainbow")
```

`app.add_middleware()` receives a middleware class as the first argument and any additional arguments to be passed to the middleware.

## Integrated middlewares { #integrated-middlewares }

  private val settingsListenerQueue = taskRunner.newQueue()

  /** User code to run in response to push promise events. */
  private val pushObserver: PushObserver = builder.pushObserver

  // Total number of pings send and received of the corresponding types. All guarded by this.
  private var intervalPingsSent = 0L
  private var intervalPongsReceived = 0L
  private var degradedPingsSent = 0L
  private var degradedPongsReceived = 0L

    }

    /**
     * Get the maximum size for receive operations
     *
     * @return maximum receive size in bytes
     */
    public int getMaxReceiveSize() {
        return maxReceiveSize;
    }

    /**
     * Set the maximum size for receive operations
     *
     * @param maxReceiveSize maximum receive size in bytes
     */
    public void setMaxReceiveSize(int maxReceiveSize) {

 *
 * Note that the state progression is independent for each peer. Arriving at a gracefully-closed
 * state indicates that a peer has sent all of its outgoing messages and received all of its
 * incoming messages. But it does not guarantee that the other peer will successfully receive all of
 * its incoming messages.
 */
interface WebSocket {
  /** Returns the original request that initiated this web socket. */
  fun request(): Request

  /**

 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"time"

	miniogo "github.com/minio/minio-go/v7"

  private var failed = false

  /** Total number of pings sent by this web socket. */
  private var sentPingCount = 0

  /** Total number of pings received by this web socket. */
  private var receivedPingCount = 0

  /** Total number of pongs received by this web socket. */
  private var receivedPongCount = 0

  /** True if we have sent a ping that is still awaiting a reply. */
  private var awaitingPong = false

    response: Response,
  ) {
  }

  /**
   * Invoked when a result is served from the cache. The Response provided is the top level
   * Response and normal event sequences will not be received.
   *
   * This event will only be received when a Cache is configured for the client.
   */
  open fun cacheHit(
    call: Call,
    response: Response,
  ) {
  }

  /**

    sockets and HTTP/2 connections.**

    Previously if you configured a ping interval that would cause OkHttp to send
    pings, but it did not track whether the reply pongs were received. With this
    update OkHttp requires that every ping receive a response: if it does not
    the connection will be closed and the listener's `onFailure()` method will
    be called.

///

## Create a middleware { #create-a-middleware }

To create a middleware you use the decorator `@app.middleware("http")` on top of a function.

The middleware function receives:

* The `request`.
* A function `call_next` that will receive the `request` as a parameter.
    * This function will pass the `request` to the corresponding *path operation*.
    * Then it returns the `response` generated by the corresponding *path operation*.