func registerAPIRouter(router *mux.Router) {
	// Initialize API.
	api := objectAPIHandlers{
		ObjectAPI: newObjectLayerFn,
	}

	// API Router
	apiRouter := router.PathPrefix(SlashSeparator).Subrouter()

	var routers []*mux.Router
	for _, domainName := range globalDomainNames {
		if IsKubernetes() {

	kmsAPIVersion       = "v1"
	kmsAPIVersionPrefix = SlashSeparator + kmsAPIVersion
)

type kmsAPIHandlers struct{}

// registerKMSRouter - Registers KMS APIs
func registerKMSRouter(router *mux.Router) {
	kmsAPI := kmsAPIHandlers{}
	kmsRouter := router.PathPrefix(kmsPathPrefix).Subrouter()

	KMSVersions := []string{
		kmsAPIVersionPrefix,
	}

	gz, err := gzhttp.NewWrapper(gzhttp.MinSize(1000), gzhttp.CompressionLevel(gzip.BestSpeed))

const (
	prometheusJWT    prometheusAuthType = "jwt"
	prometheusPublic prometheusAuthType = "public"
)

// registerMetricsRouter - add handler functions for metrics.
func registerMetricsRouter(router *mux.Router) {
	// metrics router
	metricsRouter := router.NewRoute().PathPrefix(minioReservedBucketPath).Subrouter()
	authType := prometheusAuthType(strings.ToLower(env.Get(EnvPrometheusAuthType, string(prometheusJWT))))

	auth := AuthMiddleware

type adminAPIHandlers struct{}

// registerAdminRouter - Add handler functions for each service REST API routes.
func registerAdminRouter(router *mux.Router, enableConfigOps bool) {
	adminAPI := adminAPIHandlers{}
	// Admin router
	adminRouter := router.PathPrefix(adminPathPrefix).Subrouter()

	adminVersions := []string{
		adminAPIVersionPrefix,
	}

	// Add server metrics router
	registerMetricsRouter(router)

	// Add STS router always.
	registerSTSRouter(router)

	// Add KMS router
	registerKMSRouter(router)

	// Add API router
	registerAPIRouter(router)

	router.Use(globalMiddlewares...)

	return router, nil

    sub_router = APIRouter(lifespan=subrouter_lifespan)

    router = APIRouter(lifespan=router_lifespan)
    router.include_router(sub_router)

    app = FastAPI(lifespan=lifespan)
    app.include_router(router)

    @app.get("/")
    def main(request: Request) -> dict[str, str]:
        assert request.state.app
        assert request.state.router
        assert request.state.sub_router

from fastapi.testclient import TestClient
from pydantic import BaseModel


def custom_generate_unique_id(route: APIRoute):
    return f"foo_{route.name}"


def custom_generate_unique_id2(route: APIRoute):
    return f"bar_{route.name}"


def custom_generate_unique_id3(route: APIRoute):
    return f"baz_{route.name}"


class Item(BaseModel):
    name: str
    price: float


class Message(BaseModel):

@router.get("/router-depends/")
async def router_depends(commons: dict = Depends(common_parameters)):
    return {"in": "router-depends", "params": commons}


@router.get("/router-decorator-depends/", dependencies=[Depends(common_parameters)])
async def router_decorator_depends():
    return {"in": "router-decorator-depends"}


app.include_router(router)

client = TestClient(app)

        assert data == ["app", "index"]


def test_routerindex():
    client = TestClient(app)
    with client.websocket_connect("/router") as websocket:
        data = json.loads(websocket.receive_text())
        assert data == ["app", "router2", "router", "routerindex"]


def test_routerprefixindex():
    client = TestClient(app)
    with client.websocket_connect("/prefix/") as websocket:

We are importing the submodule `items` directly, instead of importing just its variable `router`.

This is because we also have another variable named `router` in the submodule `users`.

If we had imported one after the other, like:

```Python
from .routers.items import router
from .routers.users import router
```