# 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.

        assertEquals(0x80, SmbConstants.FLAGS_RESPONSE);
    }

    /**
     * Test interaction with SmbTransport using Mockito.
     * This demonstrates mocking capabilities for testing.
     */
    @Test
    @DisplayName("Mock interaction example with SmbTransport")
    void mockTransportInteraction() {
        // Create a mock of SmbTransport from jcifs package

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 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *

~~ or more contributor license agreements.  See the NOTICE file
~~ distributed with this work for additional information
~~ regarding copyright ownership.  The ASF licenses this file
~~ to you under the Apache License, Version 2.0 (the
~~ "License"); you may not use this file except in compliance
~~ with the License.  You may obtain a copy of the License at
~~
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~~

But still, FastAPI got quite some inspiration from Requests.

**Requests** is a library to *interact* with APIs (as a client), while **FastAPI** is a library to *build* APIs (as a server).

They are, more or less, at opposite ends, complementing each other.

Requests has a very simple and intuitive design, it's very easy to use, with sensible defaults. But at the same time, it's very powerful and customizable.

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

 */
public class TransportExceptionTest {

    @Nested
    @DisplayName("Constructor Tests")
    class ConstructorTests {

        @Test
        @DisplayName("Should create exception with no arguments")
        void testDefaultConstructor() {
            TransportException exception = new TransportException();

            assertNotNull(exception);
            assertNull(exception.getMessage());

		t.Errorf("Age should equals to 5, but got %v", user.Age)
	} else if user.Active != true {
		t.Errorf("Active should be true, but got %v", user.Active)
	}
	checkUpdatedAtChanged("Updates with map", user.UpdatedAt)
	checkOtherData("Updates with map")

	var result2 User
	if err := DB.Where("id = ?", user.ID).First(&result2).Error; err != nil {
		t.Errorf("errors happened when query: %v", err)
	} else {
		CheckUser(t, result2, *user)

        assertEquals(123L, dictionaryItem.getId());
    }

    public void test_getId_negativeValue() {
        // Test with negative ID value
        dictionaryItem.id = -456L;
        assertEquals(-456L, dictionaryItem.getId());
    }

    public void test_getId_maxValue() {
        // Test with maximum Long value
        dictionaryItem.id = Long.MAX_VALUE;
        assertEquals(Long.MAX_VALUE, dictionaryItem.getId());
    }

     * Call init() to initialize with a key before use.
     */
    public RC4() {
    }

    /**
     * Constructs and initializes an RC4 cipher with the specified key.
     *
     * @param key the encryption key
     */
    public RC4(final byte[] key) {
        init(key, 0, key.length);
    }

    /**
     * Initializes the RC4 cipher with a key.