//go:build darwin || dragonfly || freebsd || illumos || linux || netbsd || openbsd

// This program can be used as go_android_GOARCH_exec by the Go tool.
// It executes binaries on an android device using adb.
package main

import (
	"bytes"
	"errors"
	"fmt"
	"io"
	"log"
	"os"
	"os/exec"
	"os/signal"
	"path"
	"path/filepath"
	"regexp"
	"runtime"
	"strconv"
	"strings"
	"sync"
	"syscall"
)

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package main

import (
	"bytes"
	"crypto/md5"
	"encoding/base64"
	"encoding/binary"
	"encoding/hex"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"log"
	"os"
	"path/filepath"
	"regexp"
	"slices"

Klaus Post <******@****.***> 1756435188 +0200

jiuker <******@****.***> 1748359116 +0800

```Python hl_lines="1  3  7" title="app/main.py"
{!../../docs_src/bigger_applications/app/main.py!}
```

### 🗄 `APIRouter`

🔜 👥 🗄 🎏 🔁 👈 ✔️ `APIRouter`Ⓜ:

```Python hl_lines="5" title="app/main.py"
{!../../docs_src/bigger_applications/app/main.py!}
```

///

## The main `FastAPI` { #the-main-fastapi }

Now, let's see the module at `app/main.py`.

Here's where you import and use the class `FastAPI`.

This will be the main file in your application that ties everything together.

And as most of your logic will now live in its own specific module, the main file will be quite simple.

### Import `FastAPI` { #import-fastapi }

```
.
├── app
│   ├── __init__.py
│   └── main.py
```

Здесь файл `main.py` является "точкой входа" в Ваше приложение и содержит инициализацию Вашего приложения **FastAPI**:


{* ../../docs_src/app_testing/main.py *}

### Файл тестов

<div class="termy">

```console
// اینجا هنوز متغیر محیطی رو تنظیم نکردیم
$ python main.py

// چون متغیر محیطی رو تنظیم نکردیم، مقدار پیش‌فرض رو می‌گیریم

Hello World from Python

// ولی اگه اول یه متغیر محیطی بسازیم
$ export MY_NAME="Wade Wilson"

// و بعد دوباره برنامه رو صدا کنیم
$ python main.py

// حالا می‌تونه متغیر محیطی رو بخونه

Hello Wade Wilson from Python
```

</div>

```console
// Erstelle eine Umgebungsvariable MY_NAME inline für diesen Programmaufruf
$ MY_NAME="Wade Wilson" python main.py

// main.py kann jetzt diese Umgebungsvariable lesen

Hello Wade Wilson from Python

// Die Umgebungsvariable existiert danach nicht mehr
$ python main.py

Hello World from Python
```

</div>

/// tip | Tipp

```Python hl_lines="1  3  7" title="app/main.py"
{!../../docs_src/bigger_applications/app/main.py!}
```

### Импорт `APIRouter`

Теперь мы импортируем другие суб-модули, содержащие `APIRouter`:

```Python hl_lines="4-5" title="app/main.py"
{!../../docs_src/bigger_applications/app/main.py!}
```