You are designing a system where a function needs to accept an arbitrary number of arguments and process them. Which type of function would you use?
- Anonymous function
- Callback function
- Recursive function
- Variadic function
Variadic functions in Go allow you to define functions that can accept a variable number of arguments. They are declared using an ellipsis (...) before the type of the last parameter in the function signature.
The size of the '_______' data type in Go on a 64-bit system is 8 bytes.
- float64
- int64
- string
- uint64
The float64 data type in Go occupies 8 bytes on a 64-bit system. It's used to represent decimal numbers with double-precision floating-point precision, making it suitable for a wide range of numerical values.
How can you create an instance of a struct in Go?
- Using the := operator
- Using the make function
- Using the new keyword
- Using the struct keyword
In Go, you can create an instance of a struct using the := operator followed by the struct name and then initializing the struct fields. This creates a new instance of the struct and assigns it to the variable.
Which testing framework in Go is commonly used for writing unit tests?
- go test
- gunit
- testify
- testing
The "go test" command is a standard and widely used testing framework in Go specifically designed for writing unit tests. It simplifies the process of writing and executing tests for individual functions or packages.
The _______ keyword in Go is used to create a closure.
- defer
- func
- package
- return
The "func" keyword in Go is used to declare functions. Closures in Go are anonymous functions that can access variables declared in their surrounding scope. By using the "func" keyword, developers can create closures, which are useful for handling tasks like callbacks.
In Go, what is a closure?
- A closure is a function value that references variables from outside its body.
- A function that has no parameters.
- A function that operates only on strings.
- A function that returns an error.
A closure in Go refers to a function value that references variables from outside its body. This allows the function to access and manipulate variables defined outside its own scope, even after the enclosing function has finished executing.
Code coverage measures the extent to which your _______ is covered by your test suite.
- Functions
- Logic branches
- Source code
- Variables
Code coverage measures the extent to which your source code is covered by your test suite. This means that it evaluates how much of your actual code is executed by your tests, ensuring comprehensive testing.
The json.Marshal function in Go returns a ________ and an error.
- map
- slice
- byte
- []byte
The correct answer is option 4, "[]byte". The json.Marshal function in Go converts a Go data structure to JSON format and returns a []byte slice containing the JSON representation of the data along with an error, if any.
The _______ middleware in Go is commonly used for handling tasks such as logging, authentication, and rate limiting.
- Context Middleware
- Gorilla Mux
- Logger Middleware
- Negroni
Negroni is a popular middleware package in Go, often used for tasks like logging, authentication, and rate limiting. Middleware like Negroni simplifies the handling of common concerns across different parts of a web application.
Anonymous functions in Go can access and modify variables from the _______ scope.
- block
- global
- local
- package
Anonymous functions in Go can access and modify variables from the enclosing block's scope. This is often used in closures, where the function captures variables from the surrounding context.
Suppose you are building a web application in Go, and you need to store user sessions efficiently. How would you utilize maps for this purpose, and what considerations would you take into account?
- Using a map with session IDs as keys and session data as values
- Using a map with session IDs as keys and user IDs as values
- Using a map with user IDs as keys and session data as values
- Using a map with user IDs as keys and user data as values
Storing user sessions efficiently can be achieved by using a map with session IDs as keys and session data as values. This allows for quick access to session data using the session ID. Additionally, consider managing session expiration and cleanup to avoid memory leaks.
Suppose you're building an API that requires authentication using OAuth 2.0. Walk through the flow of how a client would obtain an access token and use it to access protected resources.
- Client directly requests an access token from the resource server, which verifies client credentials and returns an access token if valid. The client then uses this token to access protected resources.
- Client includes its API key in requests to the resource server, which validates the key and returns an access token for accessing protected resources.
- Client requests authorization from the authorization server, receives an authorization code, exchanges it for an access token, and uses the access token to access protected resources by including it in the Authorization header of API requests.
- Client sends username and password to the authorization server, which returns an access token directly. The client then uses this token to access protected resources.
The OAuth 2.0 authorization flow involves the client obtaining an authorization code from the authorization server, exchanging it for an access token, and then using the access token to access protected resources. This flow ensures secure authentication and authorization for API access.