API Inspection Best Practices: Ensuring API Gateway Stability and Efficiency
Published: 2024-04-12 10:17:44

## Introduction

In today's digital age, Application Programming Interfaces (APIs) undoubtedly play a crucial role. It is these interfaces that make our digital lives more convenient and efficient. However, like any complex system, APIs also require regular maintenance and inspection to ensure their stability and security. This leads us to the topic we're discussing today — API testing.

## API Testing

### 1. What Is API Testing?

API testing involves regularly inspecting and evaluating application programming interfaces to ensure they function correctly. The testing cycle refers to the interval between API tests, which can be flexibly adjusted based on actual circumstances. Common testing cycles may include weekly, monthly, quarterly, or annual intervals. For particularly critical APIs, daily testing may even be necessary. Importantly, the testing cycle is not fixed and should be adjusted based on actual conditions. For example, if an API undergoes significant updates recently, it may be necessary to increase the testing frequency initially to ensure everything runs smoothly.

### 2. Common API Issues and Impacts

Common issues discovered during regular API testing, conducted based on API gateways, mainly include performance bottlenecks and security issues. Through regular API testing, these issues can be promptly identified and addressed, thereby enhancing the availability, stability, and security of APIs. Additionally, the testing process allows for optimization and improvement of APIs based on real-world scenarios to meet evolving business needs and technological challenges.

### 3. Difference Between Testing and Monitoring

While testing and [monitoring](https://api7.ai/blog/api7-customized-monitoring) are both important means to ensure the normal operation of APIs, there are significant differences between them. Monitoring is a real-time, continuous process of data collection and analysis aimed at promptly detecting and responding to abnormal situations, such as performance degradation or security threats.

In contrast, testing can be a periodic, comprehensive inspection process that focuses more on evaluating the overall health of APIs and providing recommendations for improvement. Testing may include aspects such as code reviews, performance testing, and security vulnerability scanning, aiming to identify and resolve potential issues to enhance the overall quality of APIs.

In summary, monitoring serves as a real-time "guard", while testing serves as a periodic "check-up".

![Detecting APIs regularly](https://static.apiseven.com/uploads/2024/04/12/qGr5bl10_11668340_20945203.jpg)

## How to Conduct API Testing Using APISIX/API7 Enterprise

Using APIs of banking clients as an example, regular testing is crucial, given that banking APIs involve financial transactions and sensitive data, requiring high levels of security and stability. Here are recommendations for best practices in testing APIs for banking clients:

### 1. Establish Testing Objectives and Scope

- Security Checks: Ensure APIs have no security vulnerabilities, such as injection attacks or cross-site scripting.

- Performance Evaluation: Check if APIs' response time and throughput meet business requirements.

- Data Integrity Verification: Ensure data transmitted through APIs is complete and not tampered with.

### 2. Develop Detailed Testing Plans

- Testing Cycle: Set testing intervals based on business requirements and system importance, such as weekly, monthly, or quarterly testing.

- Testing Personnel: Assign dedicated testing teams, including security experts and performance testers.

- Testing Tools: Select suitable automated testing tools, such as [OWASP Zap](https://en.wikipedia.org/wiki/OWASP_ZAP) and [Postman](https://www.postman.com/), for security and functionality testing.

### 3. Execute Testing Steps

#### 1. Security Testing

- Use automated tools for common web security vulnerability scans, such as SQL injection and cross-site scripting.

- Utilize APISIX/API7 Enterprise's [`fault injection`](https://docs.api7.ai/cloud/references/plugins/traffic-management/fault-injection) plugin to simulate responses to extreme risk scenarios for specific APIs.

- Check the completeness of API authentication and authorization mechanisms, ensuring each API in APISIX/API7 Enterprise has authentication plugins enabled, such as [`key-auth`](https://docs.api7.ai/hub/key-auth), basic-auth, and [`jwt-auth`](https://docs.api7.ai/hub/jwt-auth).

- Verify API rate limiting and protection measures, ensuring each API in APISIX/API7 Enterprise has rate limiting plugins enabled, such as [`limit-count`](https://docs.api7.ai/hub/limit-count), [`limit-req`](https://docs.api7.ai/hub/limit-req), and limit-conn.

- Review API sensitive data protection measures (e.g., user personal information, transaction data) by enabling plugins like [`data-mask`](https://docs.api7.ai/hub/data-mask) in APISIX/API7 Enterprise or considering integration with vault.

#### 2. Performance Testing

- Simulate multiple user concurrent requests to test API throughput and response time, reporting performance metrics through integration with monitoring systems like [`Prometheus`](https://docs.api7.ai/hub/prometheus) or [`Datadog`](https://docs.api7.ai/hub/datadog) via APISIX/API7 Enterprise.

- Assess API performance under different loads, ensuring the system can handle sudden high traffic and implementing appropriate API degradation strategies through plugins like [`api-breaker`](https://apisix.apache.org/docs/apisix/plugins/api-breaker/) in APISIX/API7 Enterprise.

#### 3. Data Integrity Checks

- Request data through APIs and compare it with raw data in the database to ensure data integrity.

- Utilize APISIX/API7 Enterprise to integrate with logging systems like [`Kafka`](https://docs.api7.ai/hub/kafka-logger), [`ClickHouse`](https://docs.api7.ai/hub/clickhouse-logger), or [`Skywalking`](https://apisix.apache.org/docs/apisix/plugins/skywalking/) to report API logs and verify all data transmissions are correctly recorded.

#### 4. Functionality Validation

- Verify the proper functioning of various API features using automated testing tools.

- Use APISIX/API7 Enterprise's fault injection plugin to simulate common fault scenarios and observe API responses.

- Check if API responses meet expectations, including error handling and exception processing.

### 4. Analysis and Reporting of Testing Results

- Result Analysis: Conduct in-depth analysis of issues

 discovered during testing to determine their causes and scope of impact.

- Testing Report: Compile detailed testing reports, including testing time, personnel, discovered issues, analysis of issues, and improvement recommendations.

- Issue Tracking and Resolution: Establish a problem tracking mechanism to ensure discovered issues are promptly resolved.

### 5. Continuous Improvement and Iteration

- Feedback Loop: Adjust testing plans and steps based on testing results and business requirements.

- Technology Updates: Stay updated on the latest API security, API gateway, and related technologies to continuously update testing tools and strategies for better integration with APISIX/API7 Enterprise.

- Personnel Training: Regularly train testing personnel to enhance their professional skills and security awareness.

## Conclusion

API testing is an essential step in ensuring the healthy operation of APIs. Through regular testing, handling testing results, and subsequent optimization, the quality of APIs can be continuously improved to provide users with a better experience. For clients using API management tools like [Apache APISIX](https://api7.ai/apisix) / [API7 Enterprise](https://api7.ai/enterprise), the testing process can be more convenient and efficient. These tools provide rich features and plugins to comprehensively inspect various aspects of APIs and provide detailed testing reports and data analysis.