无法使用 https callable return 来自云函数的数据

Question

我正在从我的 Angular 应用程序调用以下云函数，但返回的值始终为 null，即使云函数正确记录了结果。不确定我做错了什么。

我的Angular代码如下：

const data = {test: testToProcess};
const process = this.fns.httpsCallable("gprocess"); // fns is Angular Fire Functions
process(data)
  .toPromise() // since Angular Fire function returns an observable, Iam converting to a promise
  .then(
    (result) => {
      console.log("function called: " + JSON.stringify(result));
    },
    (err) => {
      console.log("Function call error " + JSON.stringify(err));
    }
  );

我的云函数代码如下：

import * as functions from "firebase-functions";
const fs = require("fs");
const { google } = require("googleapis");
const script = google.script("v1");
const scriptId = "MY_SCRIPT_ID";

export const gprocess = functions.https.onCall(async (data: any, context: any) => {
const test = data.test;

return fs.readFile("gapi_credentials.json", (err: any, content: string) => {
  if (err) {return err;}
  const credentials = JSON.parse(content); // load the credentials
  const { client_secret, client_id, redirect_uris } = credentials.web;
  const googleAuth = require("google-auth-library");
  const functionsOauth2Client = new googleAuth.OAuth2Client(client_id, client_secret, redirect_uris); // Constuct an auth client
  functionsOauth2Client.setCredentials({refresh_token: credentials.refresh_token,}); // Authorize a client with credentials
  
  return runScript(functionsOauth2Client,scriptId,JSON.stringify(test))
    .then((scriptData: any) => {
      console.log("Script data in main function is" + JSON.stringify(scriptData));
      return scriptData;
    })
    .catch((error) => {return error;}); 
   });
 });

function runScript(auth: any, scriptid: string, test: any) {
 return new Promise(function (resolve, reject) {
 script.scripts.run({
      auth: auth, 
      scriptId: scriptid,
      resource: {function: "doGet",devMode: true,parameters: test}
    })
  .then((err: any, respons: any) => {
    if (err) {
      console.log("API returned an error: " + JSON.stringify(err));
      resolve(err);
    } else if (respons) {
      console.log("Script is run and response is " + JSON.stringify(respons));
      resolve(respons);
    }
  });
});
}

angular 函数在完成对云函数的处理之前返回此结果。 IT 不等待云功能返回结果。

detailed.component.ts:691 function called: null

一段时间后，结果会记录在云函数控制台上，但不会返回到 angular 客户端。云函数上的日志如下，如下图记录了正确的结果：

5:53:32.633 PM  gpublish Function execution started
5:53:32.694 PM  gpublish Function execution took 61 ms, finished with status code: 204
5:53:33.185 PM  gpublish Function execution started
5:53:33.804 PM  gpublish Function execution took 620 ms, finished with status code: 200
5:54:31.494 PM  gpublish Script is run and response is : {"config":... some result}
5:54:31.593 PM  gpublish Script data in main function is{"config":... some result}

请帮忙！

Answer 1

您的函数未正确return承诺解析数据以序列化并发送给客户端。问题是 fs.readFile 实际上 return 并不是一个承诺。它是异步的，return什么都没有，这就是客户端将收到的内容。正在调用回调，但回调中的任何内容都不会影响客户端看到的内容。

您将需要找到另一种处理文件的方法 I/O，它可以是同步的（例如 fs.readFileSync），也可以实际使用 promises 而不仅仅是异步回调。

Answer 2

如上所述，我更改了代码以使用 readFileSync（谢谢 Doug！）此外，我对从云函数发送回 Angular 客户端的数据进行了字符串化处理。

我的云函数现在看起来像这样：

import * as functions from "firebase-functions";
const fs = require("fs");
const { google } = require("googleapis");
const script = google.script("v1");
const scriptId = "MY_SCRIPT_ID";

export const gprocess = functions.https.onCall(
   async (data: any, context: any) => {
   try {
     const test = data.test;
     const content = fs.readFileSync("credentials.json"); // CHANGED TO READFILESYNC
     const credentials = JSON.parse(content); 
     const { client_secret, client_id, redirect_uris } = credentials.web;
  
     const googleAuth = require("google-auth-library");
     const functionsOauth2Client = ... some code to construct an auth client and authorise it
  
    return runScript(functionsOauth2Client,scriptId,JSON.stringify(test)).then((scriptData: any) => {
    return JSON.stringify(scriptData); // STRINGIFIED THE DATA
    });
 } catch (err) {
  return JSON.stringify(err);
 }
});

  function runScript(auth: any, scriptid: string, test: any) {
    return new Promise(function (resolve, reject) {
   
    script.scripts.run({auth: auth,scriptId: scriptid,resource: {function: "doGet",parameters: test}})
     .then((respons: any) => {resolve(respons.data);})
     .catch((error: any) => {reject(error);});
  });
  }

无法使用 https callable return 来自云函数的数据

Unable to return data from cloud function using https callable

javascript

node.js

firebase

google-cloud-functions

angularfire2