/**
 * A generic JUnit test which tests {@code replace(K, V, V)} operations on a concurrent map. Can't
 * be invoked directly; please see {@link
 * com.google.common.collect.testing.ConcurrentMapTestSuiteBuilder}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.

You can declare a parameter in a *path operation function* or dependency function with the type `BackgroundTasks`, and then you can use it to schedule the execution of background tasks after the response is sent.

You can import it directly from `fastapi`:

```python
from fastapi import BackgroundTasks
```

Here you will see different recipes or "how to" guides for **several topics**.

Most of these ideas would be more or less **independent**, and in most cases you should only need to study them if they apply directly to **your project**.

If something seems interesting and useful to your project, go ahead and check it, but otherwise, you might probably just skip them.

/// tip

/**
 * A generic JUnit test which tests {@code addAll(int, Collection)} operations on a list. Can't be
 * invoked directly; please see {@link com.google.common.collect.testing.ListTestSuiteBuilder}.
 *
 * @author Chris Povirk
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.

import org.junit.Ignore;

/**
 * Basic reserialization test for collections.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")

# Middleware

There are several middlewares available provided by Starlette directly.

Read more about them in the [FastAPI docs for Middleware](https://fastapi.tiangolo.com/advanced/middleware/).

::: fastapi.middleware.cors.CORSMiddleware

It can be imported from `fastapi`:

```python
from fastapi.middleware.cors import CORSMiddleware
```

::: fastapi.middleware.gzip.GZipMiddleware

It can be imported from `fastapi`:

### Return a Response Directly { #return-a-response-directly }

The most common case would be [returning a Response directly as explained later in the advanced docs](../advanced/response-directly.md){.internal-link target=_blank}.

{* ../../docs_src/response_model/tutorial003_02.py hl[8,10:11] *}

import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code put} operations on a map. Can't be invoked directly;
 * please see {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author Chris Povirk
 * @author Kevin Bourrillion
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

    for (int i = 0; i < bytesToCopy; i++) {
      buffer.put(readBuffer.get());
    }
    munch(); // buffer becomes empty here, since chunkSize divides bufferSize

    // Now process directly from the rest of the input buffer
    while (readBuffer.remaining() >= chunkSize) {
      process(readBuffer);
    }

    // Finally stick the remainder back in our usual buffer
    buffer.put(readBuffer);

        // For coverage, we'll ensure the method doesn't throw MalformedURLException for a valid URL
        // and that it attempts to create an SmbFile.
        // We cannot directly mock `new SmbFile()`, so we rely on the fact that if it doesn't throw, it's working as expected.

        // This test primarily ensures that the wrapper correctly handles the MalformedURLException