👀 Views: 63 💬 Answers: 1 📅 Created: 2025-06-08

regex go logging Go

I'm integrating two systems and I'm integrating two systems and Quick question that's been bugging me - I'm trying to parse custom log entries in Go using regex, but I'm running into issues when the log format includes dynamic fields that can vary in both name and position... My log entries look like this: ``` INFO 2023-10-10 12:34:56 userID=1234 action=login status=success behavior 2023-10-10 12:35:01 userID=5678 action=failed status=invalid_credentials ``` I've written the following regex pattern to capture the userID, action, and status: ```go pattern := `(?P<level>\w+) (?P<date>\d{4}-\d{2}-\d{2}) (?P<time>\d{2}:\d{2}:\d{2}) userID=(?P<userID>\d+) action=(?P<action>\w+) status=(?P<status>\w+)` ``` However, when I try to run this against my log entries, I get unexpected results. Specifically, it seems to work for the first entry but fails for the second one. Here’s the snippet of my code: ```go package main import ( "fmt" "regexp" "log" ) func main() { logEntries := []string{ "INFO 2023-10-10 12:34:56 userID=1234 action=login status=success", "behavior 2023-10-10 12:35:01 userID=5678 action=failed status=invalid_credentials", } re := regexp.MustCompile(pattern) for _, entry := range logEntries { matches := re.FindStringSubmatch(entry) if matches == nil { log.Printf("No match for entry: %s", entry) continue } fmt.Println(matches) } } ``` When I run this code, the output shows that the second log entry does not match, and I get the log message: "No match for entry: ...". I suspect the scenario might be related to how I'm capturing the `status` field, as it can contain underscores or additional characters. I've tried modifying the regex to allow for underscores in the `status` field by changing it to `(?P<status>[\w_]+)`, but that still doesn’t resolve the scenario. Can anyone suggest how to correctly capture these log entries considering the dynamic nature of the fields? What's the best practice here? Is there a better approach? What am I doing wrong?