Unity调用Firebase云函数异常：请求数据始终为空

尝试运行Unity版Firebase Cloud Functions官方快速入门示例，但从Unity调用函数时传入的参数数据（对象字典）始终为空。已尝试更换不同版本的Firebase SDK，问题依旧，求排查方案。

Unity端代码 #

void Start()
{
        StartCoroutine(AddNumbers(7, 7));
}

protected IEnumerator AddNumbers(int firstNumber, int secondNumber) {
        var functions = FirebaseFunctions.GetInstance(FirebaseApp.DefaultInstance);
        var func = functions.GetHttpsCallableFromURL("https://getnumbers-dxhi3lnaew-uc.a.run.app");
        var data = new Dictionary<string, object>();
        data["firstNumber"] = firstNumber;
        data["secondNumber"] = secondNumber;
        var task = func.CallAsync(data).ContinueWithOnMainThread((callTask) => {
            if (callTask.IsFaulted) {
                // The function unexpectedly failed.
                Debug.Log("FAILED!");
                Debug.Log(String.Format("  Error: {0}", callTask.Exception));
                return;
            }

            // The function succeeded.
            var result = (IDictionary)callTask.Result.Data;
            Debug.Log(String.Format("AddNumbers: {0}", result["operationResult"]));
        });
        yield return new WaitUntil(() => task.IsCompleted);
}

云函数代码 #

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

// Adds two numbers to each other.
exports.getNumbers = functions.https.onCall((data) => {
  // Numbers passed from the client.
  const firstNumber = data.firstNumber;
  const secondNumber = data.secondNumber;

  // Checking that attributes are present and are numbers.
  if (Number.isFinite(firstNumber) || !Number.isFinite(secondNumber)) {
    // Throwing an HttpsError so that the client gets the error details.
    throw new functions.https.HttpsError('invalid-argument', '!The function ' +
        'must be called with two arguments "firstNumber" and "secondNumber" ' +
        'which must both be numbers.');
  }

  // returning result.
  return {
    firstNumber: firstNumber,
    secondNumber: secondNumber,
    operator: '+',
    operationResult: firstNumber + secondNumber,
  };
});

排查方案 #

• 调用方式不匹配：你当前用GetHttpsCallableFromURL直接调用HTTP URL，但云函数是onCall类型的Callable函数。这类函数要求客户端用SDK的标准Callable接口调用，直接URL访问会导致参数解析失败。
  解决：替换为functions.GetHttpsCallable("getNumbers")，确保函数名和云函数的exports.getNumbers一致。
• 参数校验逻辑错误：云函数里的判断条件写反了，原代码if (Number.isFinite(firstNumber) || !Number.isFinite(secondNumber))会在第一个参数是数字时就抛出错误，让你误以为参数为空。应改为：

  if (!Number.isFinite(firstNumber) || !Number.isFinite(secondNumber))
  

• Firebase初始化不完整：确保Unity端Firebase依赖初始化完成后再调用函数，修改Start方法：

  void Start()
  {
      FirebaseApp.CheckAndFixDependenciesAsync().ContinueWithOnMainThread(task => {
          if (task.Result == DependencyStatus.Available) {
              StartCoroutine(AddNumbers(7, 7));
          } else {
              Debug.LogError("Firebase dependencies failed to initialize");
          }
      });
  }
  

• 重新部署云函数：确认代码修改后重新部署，执行命令：firebase deploy --only functions:getNumbers

内容的提问来源于stack exchange，提问作者Timur Gudkov