from fastapi.testclient import TestClient

app = FastAPI()


@app.get("/")
async def read_main():
    return {"msg": "Hello World"}


client = TestClient(app)


def test_read_main():
    response = client.get("/")
    assert response.status_code == 200

import (
	"bufio"
	"bytes"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func ExampleWriter() {
	w := bufio.NewWriter(os.Stdout)
	fmt.Fprint(w, "Hello, ")
	fmt.Fprint(w, "world!")
	w.Flush() // Don't forget to flush!
	// Output: Hello, world!
}

func ExampleWriter_AvailableBuffer() {
	w := bufio.NewWriter(os.Stdout)
	for _, i := range []int64{1, 2, 3, 4} {
		b := w.AvailableBuffer()
		b = strconv.AppendInt(b, i, 10)

def test_path_operation():
    response = client.get("/headers-and-object/")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Hello World"}

client = TestClient(app)


def test_path_operation():
    response = client.get("/headers/")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Hello World"}
    assert response.headers["X-Cat-Dog"] == "alone in the world"

	if err = disk.AppendFile(t.Context(), testCase.volName, pathJoin("hello-world.txt", xlStorageFormatFile), []byte("Hello World")); err != nil {
		t.Fatalf("Create a file `test` failed with %s expected to pass.", err)
	}

	// CheckFile - stat the file.
	if _, err := disk.StatInfoFile(t.Context(), testCase.volName, "hello-world.txt/"+xlStorageFormatFile, false); err != nil {
		t.Fatalf("Stat failed with %s expected to pass.", err)

    assert response.json() == openapi_schema_main


def test_main():
    response = client.get("/app")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Hello World from main app"}


def test_openapi_schema_sub():
    response = client.get("/subapi/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == openapi_schema_sub

	"io"
	"os"
	"slices"
	"strconv"
	"unicode"
)

func ExampleBuffer() {
	var b bytes.Buffer // A Buffer needs no initialization.
	b.Write([]byte("Hello "))
	fmt.Fprintf(&b, "world!")
	b.WriteTo(os.Stdout)
	// Output: Hello world!
}

func ExampleBuffer_reader() {
	// A Buffer can turn a string or a []byte into an io.Reader.
	buf := bytes.NewBufferString("R29waGVycyBydWxlIQ==")

from fastapi import FastAPI
from fastapi.testclient import TestClient
from fastapi.websockets import WebSocket

app = FastAPI()


@app.get("/")
async def read_main():
    return {"msg": "Hello World"}


@app.websocket("/ws")
async def websocket(websocket: WebSocket):
    await websocket.accept()
    await websocket.send_json({"msg": "Hello WebSocket"})
    await websocket.close()


def test_read_main():

    assertEquals("Hello, World!", builder.toString());
  }

  public void testAppendMethods() throws IOException {
    StringBuilder builder = new StringBuilder();
    Writer writer = new AppendableWriter(builder);

    writer.append("Hello,");
    writer.append(' ');
    writer.append("The World Wide Web", 4, 9);
    writer.append("!");

    assertEquals("Hello, World!", builder.toString());
  }

```txt
Hello, World from Flask!
```

А если вы перейдёте по <a href="http://localhost:8000/v2" class="external-link" target="_blank">http://localhost:8000/v2</a>, вы увидите HTTP‑ответ от FastAPI:

```JSON
{
    "message": "Hello World"
}