How would you create a custom HTTP handler struct in Go?

  • Using a function with a specific signature.
  • By extending the http.Handler interface.
  • Implementing the http.ResponseWriter interface.
  • Defining a new route in the main function.
In Go, you create a custom HTTP handler by defining a struct that implements the http.Handler interface. This interface requires implementing the ServeHTTP method, which allows you to specify how the handler should respond to HTTP requests. By using this method, you have full control over handling requests, parsing data, and crafting responses within your custom handler.

In SQL, the _____ statement is used to extract data from a database.

  • SELECT
  • INSERT
  • UPDATE
  • DELETE
The correct answer is "SELECT." In SQL, the SELECT statement is used to extract data from a database. It allows you to retrieve specific columns or all columns from one or more tables. You can also use various clauses and keywords with the SELECT statement to filter, aggregate, and manipulate the data you retrieve. This statement is fundamental for querying and retrieving data from a database.

Explain how you would implement JWT (JSON Web Tokens) authentication in a Gin application.

  • Create middleware for JWT authentication
  • Use basic authentication with username and password
  • Implement OAuth2 for user authentication
  • Enable HTTPS for secure communication
Implementing JWT authentication in a Gin application involves creating middleware to validate JWT tokens. This middleware can be used to check the token's validity, verify the signature, and extract user information. When a request is made to a protected endpoint, this middleware can be used to authenticate and authorize users based on the JWT token. It's a secure way to handle user authentication without transmitting sensitive data like passwords.

How would you handle URL parameters in a Go web application?

  • Accessing them directly from the URL as strings.
  • Using the Request.Params() function to retrieve them.
  • Parsing the request body to extract parameters.
  • Utilizing the net/url package to parse the URL and retrieve parameters.
In a Go web application, you typically handle URL parameters by utilizing the net/url package to parse the URL and extract parameters from it. This package provides functions to parse query parameters, form data, and other URL components. You can access these parameters using the Request.URL.Query() method, making it a convenient way to handle user input from URLs.

Explain how benchmarking can be used to identify performance bottlenecks in a Go application.

  • By comparing the Go application to applications in other programming languages.
  • By measuring the memory usage of the application.
  • By measuring the execution time of specific code segments.
  • By analyzing the syntax and structure of the code.
Benchmarking in Go involves measuring the execution time of specific code segments or functions. By profiling different parts of the application, you can identify which parts are consuming the most time and resources. These identified bottlenecks can then be optimized to improve overall performance. Benchmarking allows you to focus on actual performance metrics, such as execution time, rather than subjective factors like syntax or language choice.

Describe a scenario where it would be appropriate to use a switch statement over multiple if-else statements in Go.

  • When dealing with asynchronous code that involves callbacks.
  • When evaluating a single expression against multiple constant values with distinct actions.
  • When you need to handle complex conditions that require multiple levels of nesting.
  • When you want to handle input from a user in a console application.
In Go, a switch statement is appropriate when you need to evaluate a single expression against multiple constant values, and each constant value corresponds to a distinct action or behavior. This helps to keep the code concise and easier to read compared to using multiple nested if-else statements. It's particularly useful when you have a clear mapping between the input value and the desired outcome, making the code more maintainable and efficient.

The _______ package in Go provides functionality for measuring and displaying test coverage.

  • coverage
  • testing/coverage
  • test_coverage
  • cover
The "testing/cover" package in Go provides functionality for measuring and displaying test coverage. It allows you to analyze how much of your codebase is covered by your tests. Test coverage is a crucial metric for assessing the effectiveness of your test suite and identifying areas of your code that may not be adequately tested. It helps ensure the reliability and robustness of your Go programs.

What is an SQL injection, and how can it be prevented in Go?

  • A method to inject SQL code into the database.
  • A technique to encrypt database queries for security.
  • A way to improve database performance in Go.
  • A mechanism to create database backups.
SQL injection is a malicious technique where an attacker inserts malicious SQL code into a query, potentially gaining unauthorized access to the database or altering its contents. In Go, you can prevent SQL injection by using prepared statements and parameterized queries. These techniques ensure that user inputs are treated as data, not executable code, making it much harder for attackers to manipulate your queries. Proper input validation and sanitization are also important.

What is the purpose of the fmt.Println() function in debugging Go code?

  • To print the current date and time.
  • To print a message to the console.
  • To start the debugger.
  • To clear the screen.
The fmt.Println() function in Go is used for printing messages to the console. It's a valuable tool in debugging because it allows you to inspect the values of variables, control flow, and other information during program execution. By strategically placing fmt.Println() statements in your code, you can print out the values of variables at specific points in your code to understand what's happening and identify issues. This is often referred to as "printf-style debugging."

How does Go's type system enhance code safety and maintainability?

  • It adds complexity to the code.
  • It allows implicit type conversions.
  • It enforces static typing and catches errors early.
  • It permits dynamic typing for flexibility.
Go's type system enhances code safety and maintainability by enforcing static typing. This means that variable types are known at compile-time, catching type-related errors early in the development process. It prevents runtime type errors, making the code more reliable. Static typing also improves code maintainability by providing clear type information, making the code self-documenting and easier to understand, especially in large codebases.