如何使用firebase自动发送FCM消息？答案

【问题标题】：How to automatically send FCM message in flutter with firebase?如何使用firebase自动发送FCM消息？
【发布时间】：2022-01-17 23:25:33
【问题描述】：

我正在尝试使用以下代码自动向驱动程序发送通知：

static sendNotificationToDriver(String token, context, String ride_request_id) async
  {
    var destionation = Provider.of<AppData>(context, listen: false).dropOffLocation;
    print("this is the token: ");
    print(token);
    Map<String, String> headerMap =
    {
      'Content-Type': 'application/json',
      'Authorization': serverToken,
    };
    print(headerMap);
    Map notificationMap =
    {
      'body': 'DropOff Address, ${destionation!.placeName}',
      'title': 'New Ride Request'
    };
    print(notificationMap);
    Map dataMap =
    {
      'click_action': 'FLUTTER_NOTIFICATION_CLICK',
      'id': '1',
      'status': 'done',
      'ride_request_id': ride_request_id,
    };
    print(dataMap);
    Map sendNotificationMap =
    {
      "notification": notificationMap,
      "data": dataMap,
      "priority": "high",
      "to": token,
    };
    print(sendNotificationMap);
    var res = await http.post(
      Uri.parse('https://fcm.googleapis.com/fcm/send'),
      headers: headerMap,
      body: jsonEncode(sendNotificationMap),
    );
  }

但是，推送通知没有通过。

但是当我用这个代码使用邮递员时：

{"notification" : {"body" : "New Ride Request! Tap here to view in the app.", 
"title": "New Ride Request"}, "priority": "high", "data": {"click_action": "FLUTTER_NOTIFIATION_CLICK", 
"id": "1", "status": "done", "ride_request_id": "-MqrfzH5DKC8hTYQHy35"}, 
"to" : "dTlAVB_KTe-XZTLEYwZL10:APA91bF-D-Uh5Yb5p2uCwRr8oT90R_BXOw9qCUGMGsWqlp9RNc-WlyyNfJOKSwPArvAa3062F2XxlUJbY6xibWCYZCDPGqvaQG4xvfgByyyJ9SBxvhAgDmaP35Mqr3dfJADmprMQJ-aL"}

它有效。我不知道我做错了什么。

以下是上述打印语句的结果：

I/flutter ( 1288): {Content-Type: application/json, Authorization: AAAAUecji90:APA***********************}
I/flutter ( 1288): {body: DropOff Address, ACE Centerpoint Gen. San. Drive Wing, title: New Ride Request}
I/flutter ( 1288): {click_action: FLUTTER_NOTIFICATION_CLICK, id: 1, status: done, ride_request_id: -MqrfCLsW3Ncmfav7hdk}
I/flutter ( 1288): {notification: {body: DropOff Address, ACE Centerpoint Gen. San. Drive Wing, title: New Ride Request}, data: {click_action: FLUTTER_NOTIFICATION_CLICK, id: 1, status: done, ride_request_id: -MqrfCLsW3Ncmfav7hdk}, priority: high, to: dTlAVB_KTe-XZTLEYwZL10:APA91bF-D-Uh5Yb5p2uCwRr8oT90R_BXOw9qCUGMGsWqlp9RNc-WlyyNfJOKSwPArvAa3062F2XxlUJbY6xibWCYZCDPGqvaQG4xvfgByyyJ9SBxvhAgDmaP35Mqr3dfJADmprMQJ-aL}

【问题讨论】：

你试过在请求数据中不使用jsonEncode吗？
不，我没有尝试不使用它。是否有其他方法可以在应用内实现自动化？

标签： firebase flutter push-notification firebase-cloud-messaging http-post

【解决方案1】：

我终于设法让它工作了。我使用了以下代码：

 static sendNotificationToDriver(String token, context, String rideRequestId) async {
    if (token == null) {
      print('Unable to send FCM message, no token exists.');
      return;
    }

    try {
      await http.post(
        Uri.parse('https://fcm.googleapis.com/fcm/send'),
        headers: <String, String>{
          'Content-Type': 'application/json; charset=UTF-8',
          'Authorization': serverToken,
        },
        body: constructFCMPayload(token, rideRequestId),
      );
      print('FCM request for device sent!');
    } catch (e) {
      print(e);
    }
  }


static String constructFCMPayload(String token, String rideRequestId) {
  var res = jsonEncode({
    'token': token,
    'notification': {
      "body" : "You have a new ride request! Tap here to view in the app.",
      "title": "New Ride Request"
    },
    "priority": "high",
    'data': {
      "click_action": "FLUTTER_NOTIFIATION_CLICK",
      "id": "1",
      "status": "done",
      "ride_request_id": rideRequestId,
    },
    'to': token,

  });

  print(res.toString());
  return res;
}

但是，问题本身不是代码，而是serverToken 变量。难怪它为什么使用 Postman 而不是在应用程序中工作，因为我忘记将 "key=" 放在 serverToken 值的开头。现在，问题解决了。

【讨论】：