Question

我最近编写了一个云函数，当文档中有特定的更新并且可以正常工作时，该函数将通知发送给特定的用户。但是，正如您在每个案例内部的代码中看到的那样，我添加了代码以在案例满足时触发通知，但即使所有切换案例都失败，用户也会收到通知。对于这个问题，我真的很困惑。

一个更好的解释： ServiceStatus 有五种类型

类型-1
类型-2
类型-3
类型-4
类型-5

我希望仅在ServiceStatus中更新类型-1、3、5时才将通知发送给用户，否则应忽略函数触发器。为此，我编写了一个switch案例，但是它不能正常工作，即使两个案例不能满足要求，它也会触发所有五种类型的通知。

我的代码：

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

exports.OrderUpdates = functions.firestore.document('orders/{ServiceID}').onWrite(async (event) =>{

    const service_id = event.after.get('ServiceID');
    const title = event.after.get('ServiceStatus');
    let body;
    const fcmToken = event.after.get('FCMToken');
    const technician_name = event.after.get('TechnicianName');

    switch(title){
        case "Service Raised":
            body = "Thanks for raising a service request with us. Please wait for sometime our customer care executive will respond to your request";
            var message = {
                token: fcmToken,
                notification: {
                    title: title,
                    body: body,
                },
                "android": {
                    "notification": {
                      "channel_id": "order_updates"
                    }
                  },
                data: {
                    "Service ID": service_id,
                },
            }
        
            let response = await admin.messaging().send(message);
            console.log(response);
            break;
        case "Technician Assigned":
            body = "Our Technician " + technician_name + " has been assigned to your service request. You can contact him now to proceed further";
            var message = {
                token: fcmToken,
                notification: {
                    title: title,
                    body: body,
                },
                "android": {
                    "notification": {
                      "channel_id": "order_updates"
                    }
                  },
                data: {
                    "Service ID": service_id,
                },
            }
        
            let response = await admin.messaging().send(message);
            console.log(response);
            break;
        case "Service Completed":
            body = "Your Service request has been successfully completed. Please rate and review our service and help us to serve better. \n Thanks for doing business with us..!!";
            var message = {
                token: fcmToken,
                notification: {
                    title: title,
                    body: body,
                },
                "android": {
                    "notification": {
                      "channel_id": "order_updates"
                    }
                  },
                data: {
                    "Service ID": service_id,
                },
            }
        
            let response = await admin.messaging().send(message);
            console.log(response);
            break;
    }
});

Answer 1

如果只想在状态字段被有效更改时发送一条消息，则需要比较该字段在写操作之前和写之后的值。

为此，请从centerFromTimeline(i){ google.maps.event.trigger(this.markers[i], 'click'); }和before快照中获取字段值：

after

您会注意到，我还检查了const beforeTitle = event.before ? event.before.get('ServiceStatus') : ""; const afterTitle = event.after ? event.after.get('ServiceStatus') : "";和event.before是否存在，因为您的Cloud Function也将在创建文档时触发（此时event.after将是未定义的），并且文档删除（届时event.before将是未定义的。）

现在有了这两个值，您可以检查event.after字段是否刚被赋予一个值，该值应该触发通过一系列ServiceStatus语句发送消息的消息，例如

if

如何在Firestore中针对特定字段更新从云功能触发FCM？

1 个答案: