Software Testing Real Time Examples

 Classification of Software Testing:

Techniques of Black Box Testing:

1. Equivalence Partitioning

2. Boundary Value

3. Decision Table

4. State Transition

5. Error Guessing

Equivalence Partitioning VS Boundary Value Analysis

Types of Testing Methods:

Black Box VS White Box

Performance Testing Real Time Examples

 Performance Testing:

Types of Performance Testing:

1. Load Test

2. Stress Test

3. Scalability Test

4. Soak Test

5. Load vs Stress

JMeter Works:

Thread Group

Thread count vs Loop count

Duration Assertion

Introduction to Postman API Testing

 Postman API:

• Postman is an API Development Environment that helps developers easily test and work with APIs.
• It is used for backend testing where we enter the end-point URL, send the request to the server, and receive the response back from the server.
• It provides an easy-to-use interface for developing, testing and debugging REST APIs.
• Postman also includes a comprehensive library of pre-defined requests and response objects, making it an ideal tool for quickly testing and prototyping APIs.

Request Methods:

• GET - Get requests are used to retrieve information from the given URL.
• POST - To send the new data to an API.
• PUT - This method is used to update the existing data.
• DELETE - This is used to remove or delete the existing data.

API test actions:

1. Verify the correct HTTP status code.
2. Verify response payload: Check valid JSON body and correct field names, types, and values - including in error responses.
3. Verify response headers: HTTP server headers have implications on both security and performance.
4. Verify correct application state: This is optional and applies mainly to manual testing, or when a UI or another interface can be easily inspected.
5. Verify basic performance sanity: If an operation was completed successfully but took an unreasonable amount of time, the test fails.

HTTP Status Codes:

The Essential Performance Testing Metrics Every Developer Should Know

1.  Processor Usage: Time spent by the processor to execute non-idle threads.
2. Memory use: The available physical memory to process on a system.
3. Disk time: It is the time taken by the disk to read or write a request.
4. Bandwidth: Bits per second used by a network interface.
5. Private bytes: A specific number of bytes allocated to a particular process.
6. Response time: The time between the user’s request and the first response character.
7. Throughput: Rate of requests received per second by a network. (The formula is Throughput = (number of requests) / (total time). )
8. Maximum active sessions: Maximum number of sessions that may stay active at once.
9. Thread (user) counts: Determining the well-being of the application by checking the number of running and active threads.
10. Latency - JMeter measures the latency from just before sending the request to just after the first response has been received.
11. Think Time - the time between two transactions of user actions. 
    (Login -> Think Time -> Search -> Think Time -> Logout). 
    The average thinking time could be in the range of 3 to 10 seconds for a normal user.
12. Error rate - Measures the number of errors that occur in each request.
13. Network latency - Measures the time it takes for a request to travel from the client to the server.
14. Transaction time: Measures the time it takes for a transaction to complete.
15. Resource utilization: Measures the number of resources used by the server to handle requests.
16. Memory usage: Measures the amount of memory used by the server to process requests.
17. Load test scalability: Measures how well the server can handle an increasing amount of requests.
18. Page load time: Measures the time it takes for a web page to load.

Basic concepts of Performance Testing

 Performance Testing

• Performance testing is a type of software testing that is used to evaluate the speed, scalability, and stability of a system. It is used to ensure that the system can handle the expected load and volume of traffic.

Types:

1. Load Testing
2. Stress Testing
3. Data/Volume Testing
4. Scalability testing
5. Endurance testing
6. Spike testing

Load Testing:

• Load testing is a generic term covering Performance Testing and Stress Testing.
• Testing the app with the maximum number of users.
• To measure the performance under the expected load.

Stress Testing:

• The system is under extreme load conditions, such as peak user activity or maximum transaction throughput.
• Testing the application with MORE than the maximum number of users.
• To measure performance under a load much higher than expected.

Endurance Testing:

• Endurance Testing is done to ensure the software can handle the EXPECTED load over a long period.

Spike Testing:

• System by SUDDENLY increasing the load (e.g. the number of users or transactions) to check how it responds.

Data/Volume Testing:

• System by increasing the number of users or transactions over a PERIOD OF TIME.

Scalability testing:

• The system performs when the workload increases or decreases.

Common Performance Problem:

• Most performance problems revolve around speed, response time, load time, and poor scalability.
• A slow-running application will lose potential users.
• Long Load time - While some applications are impossible to make load in under a minute, Load time should be kept under a few seconds if possible.
• Poor response time - Response time is the time it takes from when a user inputs data into the application until the application outputs a response to that input. Generally, this should be very quick. Again if a user has to wait too long, they lose interest.
• Poor scalability - A software product suffers from poor scalability when it cannot handle the expected number of users or when it does not accommodate a wide enough range of users.
• Bottlenecking  - Bottlenecking is when either coding errors or hardware issues cause a decrease in throughput under certain loads.

Common performance bottlenecks are:

• CPU utilization
• Memory utilization
• Network utilization
• Operating System limitations
• Disk usage