You can use the `TestClient` class to test FastAPI applications without creating an actual HTTP and socket connection, just communicating directly with the FastAPI code.

Read more about it in the [FastAPI docs for Testing](https://fastapi.tiangolo.com/tutorial/testing/).

You can import it directly from `fastapi.testclient`:

```python
from fastapi.testclient import TestClient
```

Additional classes for handling WebSockets.

Provided directly by Starlette, but you can import it from `fastapi`:

```python
from fastapi.websockets import WebSocketDisconnect, WebSocketState
```

::: fastapi.websockets.WebSocketDisconnect

When a client disconnects, a `WebSocketDisconnect` exception is raised, you can catch it.

You can import it directly form `fastapi`:

```python

///

## Run your code with your debugger { #run-your-code-with-your-debugger }

Because you are running the Uvicorn server directly from your code, you can call your Python program (your FastAPI application) directly from the debugger.

---

For example, in Visual Studio Code, you can:

* Go to the "Debug" panel.
* "Add configuration...".
* Select "Python"

# Root logger option
log4j.rootLogger=INFO, stderr

# Direct log messages to stdout
log4j.appender.stderr.ImmediateFlush=true
log4j.appender.stderr=org.apache.log4j.ConsoleAppender
log4j.appender.stderr.Target=System.err
log4j.appender.stderr.layout=org.apache.log4j.PatternLayout
log4j.appender.stderr.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n


log4j.logger.jcifs: INFO
#log4j.logger.jcifs.internal.smb2.create: DEBUG

## `Depends()`

Dependencies are handled mainly with the special function `Depends()` that takes a callable.

Here is the reference for it and its parameters.

You can import it directly from `fastapi`:

```python
from fastapi import Depends
```

::: fastapi.Depends

## `Security()`

                    if (compareTypes(dirents[i], name, (SmbFile) iter.next()) < 0) {
                        break;
                    }
                } else if (sort == 3 && compareDates(dirents[i], name, (SmbFile) iter.next()) < 0) {
                    break;
                }
            }
            sorted.add(j, dirents[i]);
        }
        if (maxLen > 50) {
            maxLen = 50;
        }

    private NdrBuffer mockNdrBuffer;

    @Mock
    private NdrBuffer mockDeferredBuffer;

    @BeforeEach
    void setUp() {
        MockitoAnnotations.openMocks(this);
        // Set the deferred field directly since it's a public field, not a method
        mockNdrBuffer.deferred = mockDeferredBuffer;
        lenient().when(mockNdrBuffer.derive(anyInt())).thenReturn(mockDeferredBuffer);

	}
	if len(buf) < int(dirent.Reclen) {
		return consumed, nil, typ, fmt.Errorf("buf size %d < record length %d", len(buf), dirent.Reclen)
	}
	consumed = int(dirent.Reclen)
	if direntInode(dirent) == 0 { // File absent in directory.
		return consumed, name, typ, err
	}
	switch dirent.Type {
	case syscall.DT_REG:
		typ = 0
	case syscall.DT_DIR:

     * we must exclude each transitive dependency of each direct dependency.
     * <p>
     * Determining the transitive deps of a dependency which has been resolved as
     * non-transitive is difficult because the process of resolving removes the
     * transitive deps. To sidestep this issue, we create a configuration per
     * direct dependency version. This specially named and unique configuration

try:
    import orjson
except ImportError:  # pragma: nocover
    orjson = None  # type: ignore


@deprecated(
    "UJSONResponse is deprecated, FastAPI now serializes data directly to JSON "
    "bytes via Pydantic when a return type or response model is set, which is "
    "faster and doesn't need a custom response class. Read more in the FastAPI "