Firebase云函数中的嵌套HTTP请求

我怀疑这个问题是由于回调。当您使用firebase函数时,导出的函数应该等待所有内容执行,或者在所有内容完成执行后返回解析的承诺。在这种情况下,导出的函数将在其余执行完成之前返回。

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

const request = require("request-promise-native");

    exports.foo = functions.https.onRequest(async (req, res) => {
    const ref = admin.database().ref("/foo");
    try {
        const reqEventOptions = {
            url:
                "https://api.meetup.com/2/open_events?sign=true&photo-host=public&lat=39.747988&lon=-104.994945&page=20&key=xxxxxx",
            json: true
        };
        const bodyEventRequest = await request(reqEventOptions);
        if (!bodyEventRequest.results) {
            return res.status(200).end();
        }
        await Promise.all(
            bodyEventRequest.results.map(async result => {
                if (
                    result.name &&
                    result.description &&
                    result.group &&
                    result.group.urlname
                ) {
                    const event = {
                        name: result.name,
                        description: result.description
                    };

                    // get group information
                    const groupOptions = {
                        url:
                            "https://api.meetup.com/" +
                            result.group.urlname +
                            "?sign=true&photo-host=public&key=xxxxxx",
                        json: true
                    };

                    const categoryResultResponse = await request(groupOptions);
                    if (
                        categoryResultResponse.category &&
                        categoryResultResponse.category.name
                    ) {
                        event.category = categoryResultResponse.category.name;
                    }

                    // save to the databse
                    return ref.push(event);
                }
            })
        );
        return res.status(200).send("processed events");
    } catch (error) {
        console.error(error.message);
    }
});

快速概述更改-

• 变量使用const和let vs.var;这改进了变量的范围
• 不要像if(is good){do good things}那样进行检查,而要使用if(isbad){returnsome error}do good thin。这使得代码更易于阅读,并防止了很多嵌套的if,而您不知道它们的结尾
• 使用Promise.all()以便并行地检索每个事件的类别

您应该在代码中实现两个主要更改:

• 自 request 请求 request-promise 为了正确地链接不同的异步事件(参见Doug对您的问题的评论)
• 因为您将使用 请求承诺 Promise.all() 为了等所有的承诺都解决了再发回回复。对Firebase的不同调用也是如此 push()

因此,按照以下行修改代码应该是可行的。

我让你修改它,这样你就可以得到 name description 用于构建 event 对象。中项目的顺序 results 数组与 promises 名称 和 描述 在内部 results.forEach(groupBody => {})

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

var rp = require('request-promise');

exports.foo = functions.https.onRequest((req, res) => {
  var ref = admin.database().ref('/foo');
  var options = {
    url:
      'https://api.meetup.com/2/open_events?sign=true&photo-host=public&lat=39.747988&lon=-104.994945&page=20&key=****',
    json: true
  };
  rp(options)
    .then(body => {
      if ('results' in body) {
        const promises = [];
        for (var i = 0; i < body.results.length; i++) {
          var result = body.results[i];
          if (
            'name' in result &&
            'description' in result &&
            'group' in result &&
            'urlname' in result.group
          ) {
            var groupOptions = {
              url:
                'https://api.meetup.com/' +
                result.group.urlname +
                '?sign=true&photo-host=public&key=****',
              json: true
            };

            promises.push(rp(groupOptions));
          }
        }
        return Promise.all(promises);
      } else {
        throw new Error('err xxxx');
      }
    })
    .then(results => {
      const promises = [];

      results.forEach(groupBody => {
        if ('category' in groupBody && 'name' in groupBody.category) {
          var event = {
            name: '....',
            description: '...',
            category: groupBody.category.name
          };
          promises.push(ref.push(event));
        } else {
          throw new Error('err xxxx');
        }
      });
      return Promise.all(promises);
    })
    .then(() => {
      res.send('processed events');
    })
    .catch(error => {
      res.status(500).send(error);
    });
});

我做了一些修改,让它与节点8一起工作 package.json :

"engines": {
    "node": "8"
}

answer 以及一些Firebase云函数示例代码。

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

const request = require("request-promise-native");

exports.foo = functions.https.onRequest(
    async (req, res) => {
        var ref = admin.database().ref("/foo");
        var options = {
            url: "https://api.meetup.com/2/open_events?sign=true&photo-host=public&lat=39.747988&lon=-104.994945&page=20&key=****",
            json: true
        };
        await request(
            options,
            async (error, response, body) => {
                if (error) {
                    console.error(JSON.stringify(error));
                    res.status(500).end();
                } else if ("results" in body) {
                    for (var i = 0; i < body.results.length; i++) {
                        var result = body.results[i];
                        if ("name" in result &&
                            "description" in result &&
                            "group" in result &&
                            "urlname" in result.group
                        ) {
                            var groupOptions = {
                                url: "https://api.meetup.com/" + result.group.urlname + "?sign=true&photo-host=public&key=****",
                                json: true
                            };
                            var groupBody = await request(groupOptions);
                            if ("category" in groupBody && "name" in groupBody.category) {
                                var event = {
                                    name: result.name,
                                    description: result.description,
                                    category: groupBody.category.name
                                };
                                await ref.push(event);
                            }
                        }
                    }
                    res.status(200).send("processed events");
                }
            }
        );
    }
);