Browser Synthetic Testing

Detailed explanation

Browser Synthetic Testing, also known as synthetic monitoring or proactive monitoring, involves using scripts or bots to simulate user interactions with a website or web application. Unlike real user monitoring (RUM), which passively collects data from actual users, synthetic testing actively probes the system to identify potential issues before they impact real users. This proactive approach allows teams to identify and resolve problems related to performance, availability, and functionality before they lead to negative user experiences.

The core idea behind browser synthetic testing is to create a controlled and repeatable environment to mimic user behavior. These synthetic tests can be scheduled to run at regular intervals from various geographic locations and using different browsers and devices. By simulating user journeys, synthetic tests can detect issues such as slow page load times, broken links, JavaScript errors, and API failures.

Practical Implementation

Implementing browser synthetic testing involves several key steps:

1. Define User Journeys: Identify the critical user flows that need to be monitored. These could include actions such as logging in, searching for a product, adding items to a cart, and completing a checkout process. Prioritize journeys based on their importance to the business and their frequency of use.

2. Create Test Scripts: Develop automated scripts that simulate the defined user journeys. These scripts should accurately mimic user behavior, including navigating through pages, entering data into forms, and clicking on buttons. Tools like Selenium, Puppeteer, and Playwright are commonly used for creating these scripts.

   Example using Playwright (JavaScript):

   const { chromium } = require('playwright');
    
   (async () => {
     const browser = await chromium.launch();
     const page = await browser.newPage();
     await page.goto('https://www.example.com');
     await page.fill('#search-input', 'product');
     await page.click('#search-button');
     await page.waitForSelector('.product-list');
     console.log('Search completed successfully');
     await browser.close();
   })();

3. Configure Monitoring Locations: Choose the geographic locations from which the synthetic tests will be executed. These locations should reflect the target audience of the website or application. Using multiple locations helps to identify regional performance issues.

4. Schedule Tests: Schedule the synthetic tests to run at regular intervals. The frequency of testing should be determined based on the criticality of the user journeys and the acceptable level of risk. More critical journeys may require more frequent testing.

5. Analyze Results: Monitor the results of the synthetic tests and identify any performance issues or errors. Set up alerts to notify the team when critical thresholds are exceeded. Analyze the data to identify the root cause of the problems and implement corrective actions.

Best Practices

• Realistic Simulations: Ensure that the synthetic tests accurately simulate real user behavior. Use realistic data and mimic user interactions as closely as possible.
• Comprehensive Coverage: Cover all critical user journeys and key functionalities of the website or application.
• Regular Maintenance: Regularly update the synthetic tests to reflect changes in the website or application. Outdated tests can provide inaccurate results.
• Alerting and Reporting: Set up alerts to notify the team when critical thresholds are exceeded. Generate reports to track performance trends and identify areas for improvement.
• Integration with CI/CD: Integrate synthetic testing into the CI/CD pipeline to automatically test new releases before they are deployed to production. This helps to identify and resolve issues early in the development cycle.
• Use a Variety of Browsers and Devices: Test on different browsers (Chrome, Firefox, Safari, Edge) and devices (desktop, mobile, tablet) to ensure compatibility and optimal performance across various platforms.

Common Tools

Several tools are available for browser synthetic testing, each with its own strengths and weaknesses. Some popular options include:

• Selenium: A widely used open-source framework for automating web browsers. Selenium provides a flexible and powerful platform for creating complex synthetic tests.
• Puppeteer: A Node.js library developed by Google for controlling headless Chrome or Chromium. Puppeteer is lightweight and efficient, making it a good choice for performance testing.
• Playwright: A Node.js library developed by Microsoft that enables reliable end-to-end testing for modern web apps. Playwright supports multiple browsers, including Chrome, Firefox, Safari, and Edge.
• New Relic Synthetics: A cloud-based synthetic monitoring solution that provides a comprehensive set of features for testing and monitoring web applications.
• Datadog Synthetic Monitoring: A synthetic monitoring solution that integrates with Datadog's broader monitoring platform.
• Uptrends: A web performance monitoring tool that offers synthetic monitoring capabilities, including browser checks, API monitoring, and real user monitoring.

Benefits of Browser Synthetic Testing

• Proactive Issue Detection: Identifies performance issues and errors before they impact real users.
• Improved User Experience: Ensures that the website or application is performing optimally, leading to a better user experience.
• Reduced Downtime: Helps to prevent downtime by identifying and resolving issues before they cause outages.
• Faster Time to Resolution: Provides detailed information about the root cause of performance issues, enabling faster time to resolution.
• Continuous Monitoring: Provides continuous monitoring of the website or application, ensuring that it is always performing as expected.

Conclusion

Browser Synthetic Testing is a valuable tool for ensuring the performance, availability, and functionality of websites and web applications. By proactively simulating user interactions, synthetic tests can identify potential issues before they impact real users, leading to improved user experiences, reduced downtime, and faster time to resolution. By following best practices and using the right tools, teams can effectively implement browser synthetic testing and reap its many benefits.

Further reading

• Selenium Documentation
• Puppeteer Documentation
• Playwright Documentation
• New Relic Synthetics
• Datadog Synthetic Monitoring
• Uptrends Website Monitoring