app = FastAPI()


def get_db():
    db = DBSession()
    try:
        yield db
    finally:
        db.close()


DBDep = Annotated[DBSession, Depends(get_db)]


@app.get("/items/")
async def read_items(db: DBDep):
    return db.query(Item).all()
```

    testDistribution = providers.systemProperty('run.distribution').orElse('default').forUseAtConfigurationTime().get()
    if (providers.systemProperty('run.distribution').orElse('default').forUseAtConfigurationTime().get() == 'default') {
      String licenseType = providers.systemProperty("run.license_type").orElse("basic").forUseAtConfigurationTime().get()
      if (licenseType == 'trial') {
        setting 'xpack.ml.enabled', 'true'

        modelIds.add(modelId);

        return this;
    }

    @Override
    public Model getRawModel() {
        return rawModels.get(modelIds.get(0));
    }

    @Override
    public Model getRawModel(String modelId) {
        return rawModels.get(modelId);
    }

    public DefaultModelBuildingResult setRawModel(String modelId, Model rawModel) {

        Assertions.assertEquals("yes it is", invokerRequest.userProperties().get("user.property"));

        // maven installation
        Assertions.assertTrue(invokerRequest.systemProperties().containsKey("maven.property"));
        Assertions.assertEquals("yes it is", invokerRequest.systemProperties().get("maven.property"));
    }

    @Test
    void notHappy() {

  @Override
  protected abstract LoadingCache<K, V> delegate();

  @CanIgnoreReturnValue // TODO(b/27479612): consider removing this
  @Override
  public V get(K key) throws ExecutionException {
    return delegate().get(key);
  }

  @CanIgnoreReturnValue // TODO(b/27479612): consider removing this
  @Override
  public V getUnchecked(K key) {
    return delegate().getUnchecked(key);
  }

def test_openapi_schema(client: TestClient):
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == snapshot(
        {
            "openapi": "3.1.0",
            "info": {"title": "FastAPI", "version": "0.1.0"},
            "paths": {
                "/items/{item_id}": {
                    "get": {
                        "responses": {

@app.on_event("startup")
async def startup_event():
    items["foo"] = {"name": "Fighters"}
    items["bar"] = {"name": "Tenders"}


@app.get("/items/{item_id}")
async def read_items(item_id: str):
    return items[item_id]


def test_read_items():
    with TestClient(app) as client:
        response = client.get("/items/foo")
        assert response.status_code == 200

    return {"q": q, "skip": skip, "limit": limit}


CommonsDep = Annotated[dict, Depends(common_parameters)]


@app.get("/items/")
async def read_items(commons: CommonsDep):
    return commons


@app.get("/users/")
async def read_users(commons: CommonsDep):

    }

    @Override
    public boolean containsKey(@Nullable Object key) {
      return get(key) != null;
    }

    @Override
    public @Nullable V get(@Nullable Object key) {
      if (key instanceof Range) {
        Range<?> range = (Range<?>) key;
        RangeMapEntry<K, V> rangeMapEntry = entriesByLowerBound.get(range.lowerBound);
        if (rangeMapEntry != null && rangeMapEntry.getKey().equals(range)) {

{* ../../docs_src/first_steps/tutorial001_py310.py hl[6] *}

`@app.get("/")` 告訴 **FastAPI** 那個函式負責處理請求：

* 路徑 `/`
* 使用 <dfn title="HTTP GET 方法"><code>get</code> 操作</dfn>

/// info | `@decorator` 說明

Python 中的 `@something` 語法被稱為「裝飾器」。

你把它放在一個函式上面。像一個漂亮的裝飾帽子（我猜這是術語的來源）。

一個「裝飾器」會對下面的函式做一些事情。

在這種情況下，這個裝飾器告訴 **FastAPI** 那個函式對應於 **路徑** `/` 和 **操作** `get`。

這就是「**路徑操作裝飾器**」。

///

你也可以使用其他的操作：