函数@ lint 脚本失败答案

【问题标题】：Failed at the functions@ lint script函数@ lint 脚本失败
【发布时间】：2019-04-13 00:37:40
【问题描述】：

我正在尝试部署 Firebase，但出现此错误

error 每个 then() 都应该返回一个值或者抛出 promise/always-return

这是我的代码

'use strict'

const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);


exports.sendNotification = functions.database.ref('/notifications/{user_id}/{notification_id}').onWrite(event => {




  const user_id = event.params.user_id;
  const notification_id = event.params.notification_id;

  console.log('We have a notification from : ', user_id);



  if(!event.data.val()){

    return console.log('A Notification has been deleted from the database : ', notification_id);

  }


  const fromUser = admin.database().ref(`/notifications/${user_id}/${notification_id}`).once('value');

  return fromUser.then(fromUserResult => {

    const from_user_id = fromUserResult.val().from;

    console.log('You have new notification from  : ', from_user_id);


    const userQuery = admin.database().ref(`Users/${from_user_id}/name`).once('value');
    const deviceToken = admin.database().ref(`/Users/${user_id}/device_token`).once('value');

    return Promise.all([userQuery, deviceToken]).then(result => {

      const userName = result[0].val();
      const token_id = result[1].val();


      const payload = {
        notification: {
          title : "New Friend Request",
          body: `${userName} has sent you request`,
          icon: "default",
          click_action : "in.tvac.akshaye.lapitchat_TARGET_NOTIFICATION"
        },
        data : {
          from_user_id : from_user_id
        }
      };



      return admin.messaging().sendToDevice(token_id, payload).then(response => {

        console.log('This was the notification Feature');

      });

    });

  });

});

这是错误日志

npm 错误！代码生命周期 npm 错误！错误号 1 npm 错误！函数@ lint：eslint . npm 错误！退出状态 1 npm 错误！ npm 错误！ functions@lint 脚本失败。 npm 错误！这可能不是 npm 的问题。上面可能有额外的日志输出 npm 错误！可以在以下位置找到此运行的完整日志： npm 错误！ C:\Users\PC\AppData\Roaming\npm-cache_logs\2018-11-09T12_26_46_311Z-debug.log 错误：函数预部署错误：命令以非零退出代码终止1

【问题讨论】：

在console.log('This was the notification Feature');之后尝试return null;
@JamesPoag Omg，你是个超级英雄；）我怎样才能结束这个问题？
我发布了一个我通过 ESLint 运行的清理。请注意，我正在链接 then 而不是嵌套，并且我添加了 catch
@JamesPoag 非常感谢，问题解决了：D

标签： javascript function firebase android-studio

【解决方案1】：

链then而不是嵌套，包括catch块，总是从then返回。

'use strict'

const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);

exports.sendNotification =
    functions.database.ref('/notifications/{user_id}/{notification_id}')
        .onWrite(event => {

            const user_id = event.params.user_id;
            const notification_id = event.params.notification_id;

            console.log('We have a notification from : ', user_id);

            if (!event.data.val())
                return console.log(`A Notification has been deleted from the database : ${notification_id}`);

            return admin.database().ref(`/notifications/${user_id}/${notification_id}`).once('value')
                .then(fromUserResult => {

                    const from_user_id = fromUserResult.val().from;

                    console.log(`You have new notification from  : ${from_user_id}`);

                    const userQuery = admin.database().ref(`Users/${from_user_id}/name`).once('value');
                    const deviceToken = admin.database().ref(`/Users/${user_id}/device_token`).once('value');

                    return Promise.all([userQuery, deviceToken]);
                })
                .then(result => {

                    const userName = result[0].val();
                    const token_id = result[1].val();

                    const payload = {
                        notification: {
                            title: "New Friend Request",
                            body: `${userName} has sent you request`,
                            icon: "default",
                            click_action: "in.tvac.akshaye.lapitchat_TARGET_NOTIFICATION"
                        },
                        data: {
                            from_user_id: from_user_id
                        }
                    };

                    return admin.messaging().sendToDevice(token_id, payload);
                })
                .then(response => {
                    console.log('This was the notification Feature');
                    return null;
                })
                .catch(console.log);
        });

【讨论】：