使用 Cloud Functions 扩展 Remote Config

您可以触发一个函数来响应 Remote Config 事件（包括发布新的配置版本或回滚到旧版本）。本指南介绍如何创建 Remote Config 后台函数，以便对两个模板版本执行差异比较。

触发 Remote Config 函数

如需触发 Remote Config 函数，请先导入所需的模块：

Node.js

 // The Cloud Functions for Firebase SDK to set up triggers and logging. const {onConfigUpdated} = require("firebase-functions/remoteConfig"); const logger = require("firebase-functions/logger"); // The Firebase Admin SDK to obtain access tokens. const admin = require("firebase-admin"); const app = admin.initializeApp(); const jsonDiff = require("json-diff");
index.js

Python

 # The Cloud Functions for Firebase SDK to set up triggers and logging. from firebase_functions import remote_config_fn # The Firebase Admin SDK to obtain access tokens. import firebase_admin app = firebase_admin.initialize_app() import deepdiff import requests
main.py

然后，为更新事件定义处理程序。传递给此函数的事件对象包含模板更新的相关元数据，例如新版本号和更新时间。您还可以检索执行更新的用户的电子邮件地址，以及姓名和图片（如果有）。

下面是一个 Remote Config 函数示例，该函数会记录每个更新版本与所替换掉的版本之间的差异。该函数会检查模板对象的版本号字段，并检索当前版本（最近更新版本）以及前一个版本：

Node.js

 exports.showconfigdiff = onConfigUpdated(async (event) => {  try {  // Obtain the access token from the Admin SDK  const accessTokenObj = await admin.credential.applicationDefault()  .getAccessToken();  const accessToken = accessTokenObj.access_token;  // Get the version number from the event object  const remoteConfigApi = "https://firebaseremoteconfig.googleapis.com/v1/" +  `projects/${app.options.projectId}/remoteConfig`;  const currentVersion = event.data.versionNumber;  const prevVersion = currentVersion - 1;  const templatePromises = [];  templatePromises.push(fetch(  remoteConfigApi,  {  method: "POST",  body: new URLSearchParams([["versionNumber", currentVersion + ""]]),  headers: {Authorization: "Bearer " + accessToken},  },  ));  templatePromises.push(fetch(  remoteConfigApi,  {  method: "POST",  body: new URLSearchParams([["versionNumber", prevVersion + ""]]),  headers: {Authorization: "Bearer " + accessToken},  },  ));  // Get the templates  const responses = await Promise.all(templatePromises);  const results = responses.map((r) => r.json());  const currentTemplate = results[0];  const previousTemplate = results[1];  // Figure out the differences of the templates  const diff = jsonDiff.diffString(previousTemplate, currentTemplate);  // Log the difference  logger.log(diff);  } catch (error) {  logger.error(error);  } });
index.js

此示例使用 json-diff 和 request-promise 模块来创建差异比较并构建获取模板对象的请求。

Python

 @remote_config_fn.on_config_updated() def showconfigdiff(event: remote_config_fn.CloudEvent[remote_config_fn.ConfigUpdateData]) -> None:  """Log the diff of the most recent Remote Config template change.""" # Obtain an access token from the Admin SDK access_token = app.credential.get_access_token().access_token # Get the version number from the event object current_version = int(event.data.version_number) # Figure out the differences between templates remote_config_api = ("https://firebaseremoteconfig.googleapis.com/v1/" f"projects/{app.project_id}/remoteConfig") current_template = requests.get(remote_config_api, params={"versionNumber": current_version}, headers={"Authorization": f"Bearer {access_token}"}) previous_template = requests.get(remote_config_api, params={"versionNumber": current_version - 1}, headers={"Authorization": f"Bearer {access_token}"}) diff = deepdiff.DeepDiff(previous_template, current_template) # Log the difference print(diff.pretty())
main.py

此示例使用 deepdiff 创建差异比较，并使用 requests 构建和发送请求以获取模板对象。