您已经了解了如何使用 `TestClient` 测试 **FastAPI** 应用程序。但是到目前为止，您只了解了如何编写同步测试，而没有使用 `async` 异步函数。

在测试中能够使用异步函数可能会很有用，比如当您需要异步查询数据库的时候。想象一下，您想要测试向 FastAPI 应用程序发送请求，然后验证您的后端是否成功在数据库中写入了正确的数据，与此同时您使用了异步的数据库的库。

让我们看看如何才能实现这一点。

## pytest.mark.anyio

如果我们想在测试中调用异步函数，那么我们的测试函数必须是异步的。 AnyIO 为此提供了一个简洁的插件，它允许我们指定一些测试函数要异步调用。

## HTTPX

即使您的 **FastAPI** 应用程序使用普通的 `def` 函数而不是 `async def` ，它本质上仍是一个 `async` 异步应用程序。

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package dsync

import (
	"fmt"
	"io"
	"net/http"
	"net/http/httptest"
	"sync"
	"sync/atomic"
	"time"

	"github.com/minio/mux"
)

const numberOfNodes = 5

var (
	ds          *Dsync
	nodes       = make([]*httptest.Server, numberOfNodes) // list of node IP addrs or hostname with ports.

// 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 dsync

import (
	"bytes"
	"context"
	"errors"
	"net/http"
	"net/url"
	"time"

	xhttp "github.com/minio/minio/internal/http"
	"github.com/minio/minio/internal/rest"
)

// volume, path and operation ID.
func (n *nsLockMap) NewNSLock(lockers func() ([]dsync.NetLocker, string), volume string, paths ...string) RWLocker {
	sort.Strings(paths)
	opsID := mustGetUUID()
	if n.isDistErasure {
		drwmutex := dsync.NewDRWMutex(&dsync.Dsync{
			GetLockers: lockers,
			Timeouts:   dsync.DefaultTimeouts,
		}, pathsJoinPrefix(volume, paths...)...)
		return &distLockInstance{drwmutex, opsID}

}

func (g *Granted) isLocked() bool {
	return isLocked(g.lockUID)
}

func isLocked(uid string) bool {
	return len(uid) > 0
}

// NewDRWMutex - initializes a new dsync RW mutex.
func NewDRWMutex(clnt *Dsync, names ...string) *DRWMutex {
	restClnts, _ := clnt.GetLockers()
	sort.Strings(names)
	return &DRWMutex{
		writeLocks:           make([]string, len(restClnts)),

        "/class-instance-async-wrapped-gen-dependency/",
        "/class-instance-async-wrapped-gen-async-dependency/",
        "/wrapped-class-dependency/",
        "/wrapped-endpoint/",
        "/async-wrapped-endpoint/",
        "/wrapped-dependency-async-wrapper/",
        "/wrapped-gen-dependency-async-wrapper/",
        "/async-wrapped-dependency-async-wrapper/",

# "/path/bar". This script uses "gsutil rsync" instead, which acts on directory
# contents. About arguments to gsutil:
# "gsutil -m rsync" runs in parallel.
# "gsutil rsync -r" is recursive and makes directories work.
# "gsutil rsync -d" is "sync and delete files from destination if not present in source"

DOWNLOADS="$(mktemp -d)"
mkdir -p "$DOWNLOADS"
gsutil -m rsync -r "$TFCI_ARTIFACT_STAGING_GCS_URI" "$DOWNLOADS"

	return ies.loadMappedPolicy(ctx, name, userType, isGroup, m)
}

func (ies *IAMEtcdStore) loadMappedPolicy(ctx context.Context, name string, userType IAMUserType, isGroup bool, m *xsync.MapOf[string, MappedPolicy]) error {
	var p MappedPolicy

* Fix resync goroutine leak in ListAndWatch ([#35672](https://github.com/kubernetes/kubernetes/pull/35672), [@tatsuhiro-t](https://github.com/tatsuhiro-t))

#### client-go

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package lsync_test

import (
	"context"
	"fmt"
	"runtime"
	"sync"
	"sync/atomic"
	"testing"
	"time"

	. "github.com/minio/minio/internal/lsync"
)

func testSimpleWriteLock(t *testing.T, duration time.Duration) (locked bool) {
	ctx := t.Context()
	lrwm := NewLRWMutex()