Unmarshal logs marshaled by `logrus.TextFormatter`

main.go

package main

import (
	"encoding/json"
	"fmt"
	"regexp"
)

func main() {
	s := `time="2022-12-29T14:42:24Z" level=info msg="starting \"n=ew\" restore" logSource='pkg/co=ntroller/restore_controller.go:478' restore=velero/test-13`
	m := parse(s)
	p, _ := json.Marshal(m)
	fmt.Printf("%s\n", p)
	fmt.Printf("message=%s\n", m["msg"])
}

func parse(s string) map[string]string {
	reKV := regexp.MustCompile(`(?P<key>\w+)=["'](?P<value>(?:[^"'])+)["']|(?P<key2>\w+)=(?P<value2>\w+)`)
	re := regexp.MustCompile(`time="(?P<time>.*)" level=(?P<level>\w+) msg=(?P<msg>".*") logSource='(?P<logSource>.*)' (?P<extra>.*)`)

	matches := re.FindAllStringSubmatch(s, -1)

	output := map[string]string{}
	for _, match := range matches {
		time := match[1]
		level := match[2]
		strMsg := ""
		json.Unmarshal([]byte(match[3]), &strMsg)
		logSource := match[4]
		output["time"] = time
		output["level"] = level
		output["msg"] = strMsg
		output["logSource"] = logSource

		extra := match[5]
		extraMatches := reKV.FindAllStringSubmatch(extra, -1)
		for _, m := range extraMatches {
			if len(m[1]) == 0 {
				output[m[3]] = m[4]
			} else {
				output[m[1]] = m[2]
			}
		}
	}
	return output
}