javascript - 如何获取请求firebase云功能

Question

我正在开发一个应用程序，我想将我的用户坐标从 firestore 发送到 locationiq.com 以获取详细信息，然后将其写入 firestore 我正在使用 firebase 云功能发出 GET 请求，但我认为它失败了，有人可以帮我编写代码

我收到此错误

Function returned undefined, expected Promise or value

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

// Create and Deploy Your First Cloud Functions.
// https://firebase.google.com/docs/functions/write-firebase-functions

exports.geoCoder = functions.firestore
    .document('geocoder/{location}').onCreate((snap, context) => {
        const latitude = snap.data().coordinate.latitude;
        const longtude = snap.data().coordinate.longtude;
        var part1 = "https://us1.locationiq.com/v1/reverse.php?key=XXXXXXXXXXXXXX&lat=";
        var part2 = "&lon="
        var part3 = "&format=json"

        request(part1 + latitude + part2 + longtude + part3, { json: true }, (err, res, body) => {
          if (err) { 
          console.log(err); 
          }
          console.log(body.address);
        });
      });

更新我面临同样的错误。

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

exports.geoCoder = functions.firestore.document('geocoder/{location}').onCreate((snap, context) => {
      const latitude = snap.data().coordinate.latitude;
      const longtude = snap.data().coordinate.longtude;
      var part1 = "https://us1.locationiq.com/v1/reverse.php?key=XXXXXXXXXXXXXX&lat=";
      var part2 = "&lon="
      var part3 = "&format=json"

      request(part1 + latitude + part2 + longtude + part3, { json: true }, (err, res, body) => {
        if (err) { 
          console.log(err);
          return 0;
        }
        return admin.firestore().doc("geocoder/" + context.params.location).update({city: body.address.state})
      });
});

对不起我的英语

标签： javascriptnode.jsfirebasegoogle-cloud-firestoregoogle-cloud-functions

Answer 1

正如 Doug 在上面的评论中所解释的，你需要返回一个 Promise。

您使用的request库本机支持回调接口，但不返回 promise。

您可以使用request-promise（https://github.com/request/request-promise）和rp()“返回符合常规 Promises/A+ 的承诺”的方法，然后按如下方式调整您的代码：

const functions = require('firebase-functions');
const admin = require ('firebase-admin');
const rp = require('request-promise');
admin.initializeApp();

exports.geoCoder = functions.firestore
  .document('geocoder/{location}')
  .onCreate((snap, context) => {
    const latitude = snap.data().coordinate.latitude;
    const longtude = snap.data().coordinate.longtude;
    const part1 =
      'https://us1.locationiq.com/v1/reverse.php?key=XXXXXXXXXXXXXX&lat=';
    const part2 = '&lon=';
    const part3 = '&format=json';

    const options = {
      uri: part1 + latitude + part2 + longtude + part3,
      json: true // Automatically parses the JSON string in the response
    };

    return rp(options)
      .then(parsedBody => {
        return admin
          .firestore()
          .doc('geocoder/' + context.params.location)
          .update({ city: parsedBody.address.state });
      })
      .catch(err => {
        console.log(err);
        return null;
      });
  });