Canary 脚本的示例代码 - Amazon CloudWatch
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Canary 脚本的示例代码

本节包含代码示例,这些示例说明了 CloudWatch Synthetics Canary 脚本的一些可能函数。

Node.js 和 Puppeteer 的示例

设置 Cookie

网站依靠 Cookie 来提供自定义功能或跟踪用户。通过在 CloudWatch Synthetics 脚本中设置 Cookie,您可以模拟此自定义行为并进行验证。

例如,网站可能会显示重新访问用户的 Login (登录) 链接,而不是 Register (注册) 链接。

var synthetics = require('Synthetics'); const log = require('SyntheticsLogger'); const pageLoadBlueprint = async function () { let url = "http://smile.amazon.com/"; let page = await synthetics.getPage(); // Set cookies. I found that name, value, and either url or domain are required fields. const cookies = [{ 'name': 'cookie1', 'value': 'val1', 'url': url },{ 'name': 'cookie2', 'value': 'val2', 'url': url },{ 'name': 'cookie3', 'value': 'val3', 'url': url }]; await page.setCookie(...cookies); // Navigate to the url await synthetics.executeStep('pageLoaded_home', async function (timeoutInMillis = 30000) { var response = await page.goto(url, {waitUntil: ['load', 'networkidle0'], timeout: timeoutInMillis}); // Log cookies for this page and this url const cookiesSet = await page.cookies(url); log.info("Cookies for url: " + url + " are set to: " + JSON.stringify(cookiesSet)); }); }; exports.handler = async () => { return await pageLoadBlueprint(); };

设备模拟

您可以编写模拟各种设备的脚本,以便大致了解页面对这些设备的观看和行为。

以下示例模拟 iPhone 6 台设备。有关模拟的更多信息,请参阅 Puppeteer 文档中的 page.emulate(options)。

var synthetics = require('Synthetics'); const log = require('SyntheticsLogger'); const puppeteer = require('puppeteer-core'); const pageLoadBlueprint = async function () { const iPhone = puppeteer.devices['iPhone 6']; // INSERT URL here const URL = "https://amazon.com"; let page = await synthetics.getPage(); await page.emulate(iPhone); //You can customize the wait condition here. For instance, //using 'networkidle2' may be less restrictive. const response = await page.goto(URL, {waitUntil: 'domcontentloaded', timeout: 30000}); if (!response) { throw "Failed to load page!"; } await page.waitFor(15000); await synthetics.takeScreenshot('loaded', 'loaded'); //If the response status code is not a 2xx success code if (response.status() < 200 || response.status() :gt; 299) { throw "Failed to load page!"; } }; exports.handler = async () => { return await pageLoadBlueprint(); };

多步骤 API Canary

此示例代码演示一个带两个 HTTP 步骤的 API Canary:测试同一 API 中的正负测试用例。传递步骤配置以启用请求/响应标头的报告。此外,它隐藏 Authorization 标头和 X-Amz-Security-Token,因为它们包含用户凭证。

当此脚本用作 Canary 时,您可以查看有关每个步骤和关联的 HTTP 请求(如步骤通过/失败、持续时间和性能指标(如 DNS 查找时间和第一个字节时间))的详细信息。您可以查看 Canary 运行的 2xx、44xx 和 5xx 数。

var synthetics = require('Synthetics'); const log = require('SyntheticsLogger'); const apiCanaryBlueprint = async function () { // Handle validation for positive scenario const validatePositiveCase = async function(res) { return new Promise((resolve, reject) => { if (res.statusCode < 200 || res.statusCode > 299) { throw res.statusCode + ' ' + res.statusMessage; } let responseBody = ''; res.on('data', (d) => { responseBody += d; }); res.on('end', () => { // Add validation on 'responseBody' here if required. For ex, your status code is 200 but data might be empty resolve(); }); }); }; // Handle validation for negative scenario const validateNegativeCase = async function(res) { return new Promise((resolve, reject) => { if (res.statusCode < 400) { throw res.statusCode + ' ' + res.statusMessage; } }); }; let requestOptionsStep1 = { 'hostname': 'myproductsEndpoint.com', 'method': 'GET', 'path': '/test/product/validProductName', 'port': 443, 'protocol': 'https:' }; let headers = {}; headers['User-Agent'] = [synthetics.getCanaryUserAgentString(), headers['User-Agent']].join(' '); requestOptionsStep1['headers'] = headers; // By default headers, post data and response body are not included in the report for security reasons. // Change the configuration at global level or add as step configuration for individual steps let stepConfig = { includeRequestHeaders: true, includeResponseHeaders: true, restrictedHeaders: ['X-Amz-Security-Token', 'Authorization'], // Restricted header values do not appear in report generated. includeRequestBody: true, includeResponseBody: true }; await synthetics.executeHttpStep('Verify GET products API with valid name', requestOptionsStep1, validatePositiveCase, stepConfig); let requestOptionsStep2 = { 'hostname': ‘myproductsEndpoint.com', 'method': 'GET', 'path': '/test/canary/InvalidName(', 'port': 443, 'protocol': 'https:' }; headers = {}; headers['User-Agent'] = [synthetics.getCanaryUserAgentString(), headers['User-Agent']].join(' '); requestOptionsStep2['headers'] = headers; // By default headers, post data and response body are not included in the report for security reasons. // Change the configuration at global level or add as step configuration for individual steps stepConfig = { includeRequestHeaders: true, includeResponseHeaders: true, restrictedHeaders: ['X-Amz-Security-Token', 'Authorization'], // Restricted header values do not appear in report generated. includeRequestBody: true, includeResponseBody: true }; await synthetics.executeHttpStep('Verify GET products API with invalid name', requestOptionsStep2, validateNegativeCase, stepConfig); }; exports.handler = async () => { return await apiCanaryBlueprint(); };

Python 和 Selenium 的示例

以下示例 Selenium 代码是一个在未加载目标元素时失败并显示自定义错误消息的 Canary。

from aws_synthetics.selenium import synthetics_webdriver as webdriver from aws_synthetics.common import synthetics_logger as logger from selenium.webdriver.support.ui import WebDriverWait from selenium.webdriver.support import expected_conditions as EC from selenium.webdriver.common.by import By def custom_selenium_script(): # create a browser instance browser = webdriver.Chrome() browser.get('https://www.example.com/') logger.info('navigated to home page') # set cookie browser.add_cookie({'name': 'foo', 'value': 'bar'}) browser.get('https://www.example.com/') # save screenshot browser.save_screenshot('signed.png') # expected status of an element button_condition = EC.element_to_be_clickable((By.CSS_SELECTOR, '.submit-button')) # add custom error message on failure WebDriverWait(browser, 5).until(button_condition, message='Submit button failed to load').click() logger.info('Submit button loaded successfully') # browser will be quit automatically at the end of canary run, # quit action is not necessary in the canary script browser.quit() # entry point for the canary def handler(event, context): return custom_selenium_script()