GCP 排程開關機-省錢大作戰

內容目錄

前言

客戶剛好今天升級了compute engine的主機，但又詢問我主機的費用與實際的使用時間落差有點大，畢竟下班時間主機都是閒置的狀況，GCP的 GCE是用多少付多少，如果用滿一個月可以有折扣，另外還有購買承諾折扣能打折，但目前這專案還是以用多少付多少的方式，試想能不能設定讓他依照上班時間自動開關機，這樣主機規格可以用好一點，但又能省錢也就有了這一篇文章的誕生。

翻找了一下Google 的技術文件，有一個可以設定排程的Node.js的範例，但我按照範例上面的程式碼與步驟設定了一次，發現完全不起作用，浪費了許多時間，整體架構圖如下。

設定Google Cloud Function

以往我們開發Web Serice都是開一台VPS的主機，然後在上面開發API，那Cloud Function 就跳過VPS這一段，我們可以直接部署一個Cloud Function，我們先確定Star / Stop Instance 是可以動作的，我們再把排程補上。

請到GCP的主控台找到Cloud Function 並「建立函式」

2. 設定相關參數
函式名稱(自己定義)
區域默認即可
觸發條件 Cloud Pub/Sub
建立主題

然後，點選頁面最下面的下一步，就可以開始撰寫程式碼，這邊的範例和官方的略有不同，至於為什麼呢？
因為我用官方的完全沒辦法正常執行…。

執行階段請選擇 Node.js 10，右邊進入點輸入stopInstancePubSub，右邊程式碼區塊我放在下面，直接貼上就可以用了。

const compute = require('@google-cloud/compute');
const instancesClient = new compute.InstancesClient({fallback: 'rest'});

/**
 * Stops Compute Engine instances.
 *
 * Expects a PubSub message with JSON-formatted event data containing the
 * following attributes:
 *  zone - the GCP zone the instances are located in.
 *  label - the label of instances to stop.
 *
 * @param {!object} event Cloud Function PubSub message event.
 * @param {!object} callback Cloud Function PubSub callback indicating completion.         
 */
exports.stopInstancePubSub = async (event, context, callback) => {
  try {
    const project = await instancesClient.getProjectId();
    const payload = _validatePayload(event);
    const options = {
      project,
      zone: payload.zone,
    };
    console.log(payload.zone);
    console.log(project);
    const [instances] = await instancesClient.list(options);

    if (instances.length > 0) {
          for (const instance of instances) {
              console.log(` - ${instance.name} (${instance.machineType})`);
              instancesClient.stop({
            project,
            zone: payload.zone,
            instance: instance.name,
          });
    }

    }else{
      console.log("instance not found");
    }

    // Operation complete. Instance successfully stopped.
    const message = 'Successfully stopped instance(s)';
    console.log(message);
    callback(null, message);
  } catch (err) {
    console.log(err);
    callback(err);
  }
};

/**
 * Validates that a request payload contains the expected fields.
 *
 * @param {!object} payload the request payload to validate.
 * @return {!object} the payload object.
 */
const _validatePayload = event => {
  let payload;
  try {
    payload = JSON.parse(Buffer.from(event.data, 'base64').toString());
  } catch (err) {
    throw new Error('Invalid Pub/Sub message: ' + err);
  }
  if (!payload.zone) {
    throw new Error("Attribute 'zone' missing from payload");
  } else if (!payload.label) {
    throw new Error("Attribute 'label' missing from payload");
  }
  return payload;
};

package.json

{
  "name": "cloud-functions-schedule-instance",
  "version": "0.1.0",
  "private": true,
  "license": "Apache-2.0",
  "author": "Google Inc.",
  "repository": {
    "type": "git",
    "url": "https://github.com/GoogleCloudPlatform/nodejs-docs-samples.git"
  },
  "engines": {
    "node": ">=12.0.0"
  },
  "scripts": {
    "test": "mocha test/*.test.js --timeout=20000"
  },
  "devDependencies": {
    "mocha": "^9.0.0",
    "proxyquire": "^2.0.0",
    "sinon": "^12.0.0"
  },
  "dependencies": {
    "@google-cloud/compute": "^3.0.0"
  }
}

依樣畫葫蘆我們建立一個關閉的function

const compute = require('@google-cloud/compute');
const instancesClient = new compute.InstancesClient({fallback: 'rest'});

/**
 * Stops Compute Engine instances.
 *
 * Expects a PubSub message with JSON-formatted event data containing the
 * following attributes:
 *  zone - the GCP zone the instances are located in.
 *  label - the label of instances to stop.
 *
 * @param {!object} event Cloud Function PubSub message event.
 * @param {!object} callback Cloud Function PubSub callback indicating completion.         
 */
exports.stopInstancePubSub = async (event, context, callback) => {
  try {
    const project = await instancesClient.getProjectId();
    const payload = _validatePayload(event);
    const options = {
      project,
      zone: payload.zone,
    };
    console.log(payload.zone);
    console.log(project);
    const [instances] = await instancesClient.list(options);

    if (instances.length > 0) {
          for (const instance of instances) {
      console.log(` - ${instance.name} (${instance.machineType})`);
      instancesClient.stop({
            project,
            zone: payload.zone,
            instance: instance.name,
          });
    }

    }else{
      console.log("instance not found");
    }

    // Operation complete. Instance successfully stopped.
    const message = 'Successfully stopped instance(s)';
    console.log(message);
    callback(null, message);
  } catch (err) {
    console.log(err);
    callback(err);
  }
};

/**
 * Validates that a request payload contains the expected fields.
 *
 * @param {!object} payload the request payload to validate.
 * @return {!object} the payload object.
 */
const _validatePayload = event => {
  let payload;
  try {
    payload = JSON.parse(Buffer.from(event.data, 'base64').toString());
  } catch (err) {
    throw new Error('Invalid Pub/Sub message: ' + err);
  }
  if (!payload.zone) {
    throw new Error("Attribute 'zone' missing from payload");
  } else if (!payload.label) {
    throw new Error("Attribute 'label' missing from payload");
  }
  return payload;
};

package.json 一樣要編輯，跟上面的一模一樣，就不再貼上來了。