首页 > 解决方案 > 将消息发布到 PubSub 的云函数(由 HTTP 触发)

问题描述

我正在尝试在 Cloud Function 中创建 HTTP API - 最终发布了一条消息 t PubSub。了解,有 PubSub REST API - 但它强制我设置身份验证(在客户端) - 我想跳过并将其移动到服务器端。

下面的代码使用此命令部署为 Google Cloud Functiongcloud functions deploy helloGET --runtime nodejs8 --trigger-http

但是在浏览器中测试时,它会出错Error: could not handle the request 任何建议表示赞赏,谢谢!

"use strict";

// [START functions_pubsub_setup]
const { PubSub } = require("@google-cloud/pubsub");

// Instantiates a client
const pubsub = new PubSub();
// [END functions_pubsub_setup]

const Buffer = require("safe-buffer").Buffer;

exports.helloGET = (req, res) => {
  const topic = pubsub.topic("projects/myproject/topics/openit");

  const message = {
    data: {
      message: "req.body.message"
    }
  };

  // Publishes a message
  res.send(
    topic
      .publish(message)
      .then(() => res.status(200).send("Message published."))
      .catch(err => {
        err = `Catch block  ... ${err}`;
        console.error(err);
        res.status(500).send(err);
        return Promise.reject(err);
      })
  );
};

标签: google-cloud-platformgoogle-cloud-functionsgoogle-cloud-pubsub

解决方案


下面的代码将起作用。但是订阅者需要大约 30 秒或更长时间才能收到事件 - 对于我的用例来说太慢了:S

"use strict";
const { PubSub } = require("@google-cloud/pubsub");
const pubsub = new PubSub();
const Buffer = require("safe-buffer").Buffer;

exports.helloGET = async (req, res) => {
  var toPublish = `hello ${Date.now()}`;
  publishMessage("_REPLACE_WITH_TOPIC_NAME_", toPublish);
  res.send(`Published ${toPublish}`);
};

async function publishMessage(topicName, data) {
  console.log("=> publishMessage, data = ", data);
  const dataBuffer = Buffer.from(data);
  const topic = pubsub.topic(topicName);
  const publisher = topic.publisher();
  publisher.publish(dataBuffer, { a: "XYZ" }, function() {
    console.log("Published eventually ...");
  });
}

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