// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// 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.
//

# Middleware { #middleware }

You can add middleware to **FastAPI** applications.

A "middleware" is a function that works with every **request** before it is processed by any specific *path operation*. And also with every **response** before returning it.

* It takes each **request** that comes to your application.
* It can then do something to that **request** or run any needed code.

A scriptable web server for testing HTTP clients


### Motivation

This library makes it easy to test that your app Does The Right Thing when it
makes HTTP and HTTPS calls. It lets you specify which responses to return and
then verify that requests were made as expected.

Because it exercises your full HTTP stack, you can be confident that you're
testing everything. You can even copy & paste HTTP responses from your real web

    /** String object indicating that {@link #line} is empty */
    protected static final String EMPTY = new String();

    /** {@link BufferedReader} */
    protected final BufferedReader reader;

    /** The line that has been read */
    protected String line = EMPTY;

    /**
     * Returns an {@link Iterable} that wraps a {@link LineIterator} for use in enhanced for-loops.
     *

 * <ul>
 * <li>{@link Experimental}: Indicates that this interface or its implementation
 * may still be evolving and could change in future versions.</li>
 * <li>{@link FunctionalInterface}: Denotes that this is a functional interface,
 * allowing implementations as lambda expressions or method references.</li>
 * <li>{@link Consumer}: Signifies that this type is intended to be implemented

   * {@link #testSeededHashFunctionEquals} because the parameter to {@code goodFastHash} is a size,
   * not a seed, and because that size is rounded up. Thus, {@code goodFastHash} instances with
   * different parameters can be equal. That fact is a problem for {@code
   * testSeededHashFunctionEquals}.
   */
  public void testGoodFastHashEquals() throws Exception {

{* ../../docs_src/first_steps/tutorial001.py hl[6] *}

The `@app.get("/")` tells **FastAPI** that the function right below is in charge of handling requests that go to:

* the path `/`
* using a <abbr title="an HTTP GET method"><code>get</code> operation</abbr>

/// info | `@decorator` Info

That `@something` syntax in Python is called a "decorator".

    val c1 = factory.newConnection(pool, routeA1, 50L)

    // Running at time 50, the pool returns that nothing can be evicted until time 150.
    assertThat(pool.closeConnections(50L)).isEqualTo(100L)
    assertThat(pool.connectionCount()).isEqualTo(1)
    assertThat(c1.socket().isClosed).isFalse()

    // Running at time 60, the pool returns that nothing can be evicted until time 150.
    assertThat(pool.closeConnections(60L)).isEqualTo(90L)

        String actualUserName = ntlmRequest.getRemoteUser();

        // Assert: Verify that the returned user name is the expected one
        assertEquals(expectedUserName, actualUserName, "getRemoteUser should return the principal's name.");
    }

    /**
     * Test method for {@link NtlmHttpServletRequest#getUserPrincipal()}.
     * Verifies that the method returns the correct principal object.
     */
    @Test

      }
    }
  }


  @GwtIncompatible // Slow
  public void testBinomial_exhaustiveNotOverflowing() {
    // Tests all of the inputs to LongMath.binomial that won't cause it to overflow, that weren't
    // tested in the previous method, for k >= 3.
    for (int k = 3; k < LongMath.biggestBinomials.length; k++) {
      for (int n = 70; n <= LongMath.biggestBinomials[k]; n++) {