"میان‌افزار" یک تابع است که با هر درخواست(request) قبل از پردازش توسط هر path operation (عملیات مسیر) خاص کار می‌کند. همچنین با هر پاسخ(response) قبل از بازگشت آن نیز کار می‌کند.

* هر **درخواستی (request)** که به برنامه شما می آید را می گیرد.
* سپس می تواند کاری برای آن **درخواست** انجام دهید یا هر کد مورد نیازتان را اجرا کنید.
* سپس **درخواست** را به بخش دیگری از برنامه (توسط یک path operation مشخص) برای پردازش ارسال می کند.

    List<ProtwordsItem> protwordsItemList;

    public ProtwordsFile(final String id, final String path, final Date timestamp) {
        super(id, path, timestamp);
    }

    @Override
    public String getType() {
        return PROTWORDS;
    }

    @Override
    public String getPath() {
        return path;
    }

    @Override
    public synchronized OptionalEntity<ProtwordsItem> get(final long id) {

    List<StopwordsItem> stopwordsItemList;

    public StopwordsFile(final String id, final String path, final Date timestamp) {
        super(id, path, timestamp);
    }

    @Override
    public String getType() {
        return STOPWORDS;
    }

    @Override
    public String getPath() {
        return path;
    }

    @Override
    public synchronized OptionalEntity<StopwordsItem> get(final long id) {

Swagger UI will handle it behind the scenes for you, but it needs this "redirect" helper.

///

### Create a *path operation* to test it

Now, to be able to test that everything works, create a *path operation*:

```Python hl_lines="36-38"
{!../../docs_src/custom_docs_ui/tutorial001.py!}
```

### Test it

from fastapi import FastAPI, Path, Query, status
from fastapi.testclient import TestClient

app = FastAPI()


@app.get("/{repeated_alias}")
def get_parameters_with_repeated_aliases(
    path: str = Path(..., alias="repeated_alias"),
    query: str = Query(..., alias="repeated_alias"),
):
    return {"path": path, "query": query}


client = TestClient(app)


def test_get_parameters():

    }

    public static Path getOrigPath(final String... names) {
        return getPath("WEB-INF/", "orig", names);
    }

    public static Path getMailTemplatePath(final String... names) {
        return getPath("WEB-INF/", "mail", names);
    }

    public static Path getViewTemplatePath(final String... names) {
        return getPath("WEB-INF/", "view", names);
    }

{!> ../../docs_src/header_params/tutorial001.py!}
```

////

/// note | "Technical Details"

`Header` is a "sister" class of `Path`, `Query` and `Cookie`. It also inherits from the same common `Param` class.

But remember that when you import `Query`, `Path`, `Header`, and others from `fastapi`, those are actually functions that return special classes.

///

/// info

    private static final String FESS_CONTEXT_PATH = "fess.context.path";

    private static final String FESS_PORT = "fess.port";

    private static final String FESS_TEMP_PATH = "fess.temp.path";

    private static final String FESS_VAR_PATH = "fess.var.path";

    private static final String FESS_WEBAPP_PATH = "fess.webapp.path";

    private static final String JAVA_IO_TMPDIR = "java.io.tmpdir";

func (o *ObjectKey) keyString() string {
	if o.Lit != nil {
		return string(*o.Lit)
	}
	return o.ID.String()
}

// getLastKeypathComponent checks if the given expression is a path
// expression, and if so extracts the last dot separated component of
// the path. Otherwise it returns false.
func getLastKeypathComponent(e *Expression) (string, bool) {
	if len(e.And) > 1 ||
		len(e.And[0].Condition) > 1 ||

from pathlib import Path

from fastapi.testclient import TestClient

from docs_src.custom_response import tutorial009
from docs_src.custom_response.tutorial009 import app

client = TestClient(app)


def test_get(tmp_path: Path):
    file_path: Path = tmp_path / "large-video-file.mp4"
    tutorial009.some_file_path = str(file_path)
    test_content = b"Fake video bytes"
    file_path.write_bytes(test_content)
    response = client.get("/")