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我是 ReactNative 的新手，我正在尝试将 MongoDB Atlas 连接到我的 RN 应用程序。default app client has not yet been initialized/set即使我正在调用该Stitch.initializeDefaultAppClient(MONGODB_APP_CLIENT)方法，我也会收到一条错误消息。

我遵循了本教程：https ://levelup.gitconnected.com/react-native-mongodb-stitch-building-a-crud-application-without-a-server-3e4ae0b34d67

在 App.js 中：

import { Stitch, AnonymousCredential } from "mongodb-stitch-react-native-sdk";
...
_loadClient() {
    Stitch.initializeDefaultAppClient(MONGODB_APP_CLIENT).then(client => {
      this.setState({ client });
      this.state.client.auth
        .loginWithCredential(new AnonymousCredential())
        .then(user => {
          console.log(`Successfully logged in as user ${user.id}`);
          this.setState({ currentUserId: user.id });
          this.setState({ currentUserId: client.auth.user.id });
        })
        .catch(err => {
          console.log(`Failed to log in anonymously: ${err}`);
          this.setState({ currentUserId: undefined });
        });
    });
  }
}
...

在 Contacts.js 中：

import { Stitch, RemoteMongoClient } from "mongodb-stitch-react-native-sdk";
..
constructor() {
        super();
        this.state = {
          isLoading: true,
          users: []
        };

        this._loadClient = this._loadClient.bind(this);
    }
    componentDidMount() {
        this._loadClient();
    }

_loadClient() {
        const stitchAppClient = Stitch.defaultAppClient;
        const mongoClient = stitchAppClient.getServiceClient(
          RemoteMongoClient.factory,
          "mongodb-atlas"
        );
        const db = mongoClient.db("dbapp");
        const users = db.collection("users");
        users
          .find({ status: "new" }, { sort: { date: -1 } })
          .asArray()
          .then(docs => {
            this.setState({ users });
          })
          .catch(err => {
            console.warn(err);
          });
    }
...

上面，我分享了这个工作所必需的代码。我的代码中包含所有内容，即使我初始化了应用程序客户端，我仍然收到错误消息。会喜欢我能在这里得到的所有帮助！

完整的错误信息：

Error: default app client has not yet been initialized/set

This error is located at:
    in Contacts (at SceneView.js:9)
    in SceneView (at StackViewLayout.tsx:910)
    in RCTView (at View.js:45)
    in View (at createAnimatedComponent.js:151)
    in AnimatedComponent (at StackViewCard.tsx:106)
    in RCTView (at View.js:45)
    in View (at createAnimatedComponent.js:151)
    in AnimatedComponent (at screens.native.js:71)
    in Screen (at StackViewCard.tsx:93)
    in Card (at createPointerEventsContainer.tsx:95)
    in Container (at StackViewLayout.tsx:985)
    in RCTView (at View.js:45)
    in View (at screens.native.js:101)
    in ScreenContainer (at StackViewLayout.tsx:394)
    in RCTView (at View.js:45)
    in View (at createAnimatedComponent.js:151)
    in AnimatedComponent (at StackViewLayout.tsx:384)
    in PanGestureHandler (at StackViewLayout.tsx:377)
    in StackViewLayout (at withOrientation.js:30)
    in withOrientation (at StackView.tsx:104)
    in RCTView (at View.js:45)
    in View (at Transitioner.tsx:267)
    in Transitioner (at StackView.tsx:41)
    in StackView (at createNavigator.js:81)
    in Navigator (at createKeyboardAwareNavigator.js:12)
    in KeyboardAwareNavigator (at SceneView.js:9)
    in SceneView (at createTabNavigator.js:39)
    in RCTView (at View.js:45)
    in View (at ResourceSavingScene.js:37)
    in RCTView (at View.js:45)
    in View (at ResourceSavingScene.js:26)
    in ResourceSavingScene (at createBottomTabNavigator.js:120)
    in RCTView (at View.js:45)
    in View (at screens.native.js:101)
    in ScreenContainer (at createBottomTabNavigator.js:110)
    in RCTView (at View.js:45)
    in View (at createBottomTabNavigator.js:109)
    in TabNavigationView (at createTabNavigator.js:197)
    in NavigationView (at createNavigator.js:81)
    in Navigator (at SceneView.js:9)
    in SceneView (at SwitchView.js:12)
    in SwitchView (at createNavigator.js:81)
    in Navigator (at createAppContainer.js:430)
    in NavigationContainer (at App.js:38)
    in RCTView (at View.js:45)
    in View (at App.js:36)
    in App (at withExpoRoot.js:20)
    in RootErrorBoundary (at withExpoRoot.js:19)
    in ExpoRootComponent (at renderApplication.js:35)
    in RCTView (at View.js:45)
    in View (at AppContainer.js:98)
    in RCTView (at View.js:45)
    in View (at AppContainer.js:115)
    in AppContainer (at renderApplication.js:34)

Function.get [as defaultAppClient]
    106aa394-9652-42d9-8b6b-cda0fd593b63:183243:17
Contacts._loadClient
    106aa394-9652-42d9-8b6b-cda0fd593b63:152692:67
Contacts.proxiedMethod
    106aa394-9652-42d9-8b6b-cda0fd593b63:47391:32
Contacts.componentDidMount
    106aa394-9652-42d9-8b6b-cda0fd593b63:152685:14
Contacts.proxiedComponentDidMount
    106aa394-9652-42d9-8b6b-cda0fd593b63:47404:42
commitLifeCycles
    106aa394-9652-42d9-8b6b-cda0fd593b63:21888:28
commitAllLifeCycles
    106aa394-9652-42d9-8b6b-cda0fd593b63:23239:13
Object.invokeGuardedCallbackImpl
    106aa394-9652-42d9-8b6b-cda0fd593b63:11985:16
invokeGuardedCallback
    106aa394-9652-42d9-8b6b-cda0fd593b63:12076:37
commitRoot
    106aa394-9652-42d9-8b6b-cda0fd593b63:23433:13

作为更新，此错误是随机发生的，并且随机不发生。一分钟加载我的数据，下次我保存文件（并且应用程序重新加载）时，我再次收到错误。重新加载一堆最终修复它。但是，当然，它会再次发生。

4

2 回答 2

1

我也遇到了这个错误。const stitchAppClient = Stitch.defaultAppClient;通过将Contacts.js替换为以下内容来解决它 ：

Stitch.initializeDefaultAppClient(MONGODB_APP_CLIENT).then(client => {
      const mongoClient = stitchAppClient.getServiceClient(
          RemoteMongoClient.factory,
          "mongodb-atlas"
        );

      client.auth
        .loginWithCredential(new AnonymousCredential())
        .then(user => {
           // Your code to connect to the database and collection
         });
}

我不确定是否存在导致该错误的错误。我对 React Native 也很陌生。

希望这会有所帮助，因为我在 MongoDB 的 MongoDB Stitch React Native SDK 博客上引用了这个解决方法

于 2019-09-16T14:19:02.053 回答
1

以下更改似乎奏效了：

应用程序.js：

_loadClient() {
    Stitch.initializeDefaultAppClient(MONGODB_APP_CLIENT)
    .then(client => {
      client.auth
        .loginWithCredential(new AnonymousCredential())
        .then(user => {
          console.log(`Successfully logged in as user ${user.id}`);
          this.setState({
            currentUserId: user.id,
            currentUserId: client.auth.user.id,
            client,
          });
        })
        .catch(err => {
          console.log(`Failed to log in anonymously: ${err}`);
          this.setState({
            currentUserId: undefined,
            client,
          });
        });
    })
    .catch(err => {
      console.error(err)
    });
  }

联系人.js：

_loadClient() {
        if (Stitch.hasAppClient(MONGODB_APP_CLIENT)) {
          const app = Stitch.getAppClient(MONGODB_APP_CLIENT);
          this._loadData(app);
        } else {
          Stitch.initializeAppClient(MONGODB_APP_CLIENT)
          .then(app => this._loadData(app))
          .catch(err => console.error(err));
        }
    }
_loadData(appClient) {
      const mongoClient = appClient.getServiceClient(
          RemoteMongoClient.factory,
          "mongodb-atlas"
        );
        const db = mongoClient.db("sidapp");
        const users = db.collection("users");
        users
          .find({ type: 2 })
          .asArray()
          .then(users => {
            this.setState({ users });
          })
          .catch(err => {
            console.warn(err);
          });
    }
于 2019-09-17T23:45:39.363 回答