The key to installing Go is to select the correct version, configure environment variables, and verify the installation. 1. Go to the official website to download the installation package of the corresponding system. Windows uses .msi files, macOS uses .pkg files, Linux uses .tar.gz files and unzip them to /usr/local directory; 2. Configure environment variables, edit ~/.bashrc or ~/.zshrc in Linux/macOS to add PATH and GOPATH, and Windows set PATH to Go in the system properties; 3. Use the government command to verify the installation, and run the test program hello.go to confirm that the compilation and execution are normal. PATH settings and loops throughout the process

sync.WaitGroup is used to wait for a group of goroutines to complete the task. Its core is to work together through three methods: Add, Done, and Wait. 1.Add(n) Set the number of goroutines to wait; 2.Done() is called at the end of each goroutine, and the count is reduced by one; 3.Wait() blocks the main coroutine until all tasks are completed. When using it, please note: Add should be called outside the goroutine, avoid duplicate Wait, and be sure to ensure that Don is called. It is recommended to use it with defer. It is common in concurrent crawling of web pages, batch data processing and other scenarios, and can effectively control the concurrency process.

Using Go's embed package can easily embed static resources into binary, suitable for web services to package HTML, CSS, pictures and other files. 1. Declare the embedded resource to add //go:embed comment before the variable, such as embedding a single file hello.txt; 2. It can be embedded in the entire directory such as static/*, and realize multi-file packaging through embed.FS; 3. It is recommended to switch the disk loading mode through buildtag or environment variables to improve efficiency; 4. Pay attention to path accuracy, file size limitations and read-only characteristics of embedded resources. Rational use of embed can simplify deployment and optimize project structure.

How to quickly implement a RESTAPI example written in Go? The answer is to use the net/http standard library, which can be completed in accordance with the following three steps: 1. Set up the project structure and initialize the module; 2. Define the data structure and processing functions, including obtaining all data, obtaining single data based on the ID, and creating new data; 3. Register the route in the main function and start the server. The entire process does not require a third-party library. The basic RESTAPI function can be realized through the standard library and can be tested through the browser or Postman.

The purpose of select plus default is to allow select to perform default behavior when no other branches are ready to avoid program blocking. 1. When receiving data from the channel without blocking, if the channel is empty, it will directly enter the default branch; 2. In combination with time. After or ticker, try to send data regularly. If the channel is full, it will not block and skip; 3. Prevent deadlocks, avoid program stuck when uncertain whether the channel is closed; when using it, please note that the default branch will be executed immediately and cannot be abused, and default and case are mutually exclusive and will not be executed at the same time.

When using context.WithValue, immutable metadata within the request scope, such as user identity, request identity, etc.; it should not be used for parameter transfer or process control; 1. Appropriately pass meta information such as user ID, traceID, etc.; 2. Avoid abuse of transferring too much content such as database connection; 3. Use custom key types to prevent conflicts; 4. Do not modify the existing context value, and create a new context when it needs to be updated.

In Go language, interface{} and any are exactly the same type. Since Go1.18, any has been introduced as an alias for interface{}. The main purpose is to improve the readability and semantic clarity of the code; 1. Any is more suitable for scenarios that express "arbitrary types", such as function parameters, map/slice element types, general logic implementations, etc.; 2. Interface{} is more suitable for defining interface behavior, emphasizing interface types, or compatible with old code; 3. The performance of the two is exactly the same as the underlying mechanism, and the compiler will replace any with interface{}, which will not cause additional overhead; 4. Pay attention to type safety issues when using it, and may need to cooperate with type assertions or

It is not difficult to build a web server written in Go. The core lies in using the net/http package to implement basic services. 1. Use net/http to start the simplest server: register processing functions and listen to ports through a few lines of code; 2. Routing management: Use ServeMux to organize multiple interface paths for easy structured management; 3. Common practices: group routing by functional modules, and use third-party libraries to support complex matching; 4. Static file service: provide HTML, CSS and JS files through http.FileServer; 5. Performance and security: enable HTTPS, limit the size of the request body, and set timeout to improve security and performance. After mastering these key points, it will be easier to expand functionality.