How to implement log message deduplication and rate limiting in Go?

To implement log message deduplication and rate limiting in Go, you can use a combination of data structures and algorithms. Here's a step-by-step guide:

Import the required packages:

import (
    "sync"
    "time"
)

Create a struct to store your log messages and related metadata:

type LogMessage struct {
    Message    string
    Timestamp  time.Time
    SeenBefore bool
}

Create a map to store the log messages:

var mutex sync.Mutex
logMessages := make(map[string]*LogMessage)

Create a function to deduplicate the log messages by checking if a log message with the same content has been seen before within a certain time window:

func isDuplicateLog(message string, duration time.Duration) bool {
    // Lock the map to prevent concurrent access
    mutex.Lock()
    defer mutex.Unlock()

    // Check if the log message is a duplicate within the time window
    if logMessage, ok := logMessages[message]; ok && logMessage.SeenBefore && time.Since(logMessage.Timestamp) <= duration {
        return true
    }

    // If it's not a duplicate, update the map with the new log message
    logMessages[message] = &LogMessage{
        Message:    message,
        Timestamp:  time.Now(),
        SeenBefore: true,
    }

    return false
}

Use the isDuplicateLog function to determine if a log message is a duplicate before logging it:

func logMessage(message string) {
    // Check if the log message is a duplicate
    if isDuplicateLog(message, time.Minute) {
        // Rate limit the duplicate log messages
        return
    }

    // Log the non-duplicate log messages
    fmt.Println(message)
}

This implementation uses a map to store the log messages, where the key is the log message content and the value is a struct that contains the message, timestamp, and a boolean flag indicating whether the message has been seen before. The isDuplicateLog function checks if the log message is a duplicate based on the elapsed time since it was last seen. If it's not a duplicate, it updates the map accordingly. The logMessage function uses isDuplicateLog to determine if a log message is a duplicate and rate limits it if necessary.