repo_description: CoreDNS is a DNS server that chains plugins
repo_topics: cncf coredns dns-server go plugin service-discovery
code: //go:build ignore
  
  // generates plugin/chaos/zowners.go.
  
  package main
  
  import (
  	"bufio"
  	"fmt"
  	"log"
  	"os"
  	"sort"
  	"strings"
  )
  
  func main() {
  	// top-level OWNERS file
  	o, err := owners("CODEOWNERS")
  	if err != nil {
  		log.Fatal(err)
  	}
  
  	golist := `package chaos
  
  // Owners are all GitHub handlers of all maintainers.
  var Owners = []string{`
  	c := ", "
  	for i, a := range o {
  		if i == len(o)-1 {
  			c = "}"
  		}
  		golist += fmt.Sprintf("%q%s", a, c)
  	}
  	// to prevent `No newline at end of file` with gofmt
  	golist += "\n"
  
  	if err := os.WriteFile("plugin/chaos/zowners.go", []byte(golist), 0644); err != nil {
  		log.Fatal(err)
  	}
  	return
  }
  
  func owners(path string) ([]string, error) {
  	// simple line, by line based format
  	//
  	// # In this example, @doctocat owns any files in the build/logs
  	// # directory at the root of the repository and any of its
  	// # subdirectories.
  	// /build/logs/ @doctocat
  	f, err := os.Open(path)
  	if err != nil {
  		return nil, err
  	}
  	scanner := bufio.NewScanner(f)
  	users := map[string]struct{}{}
  	for scanner.Scan() {
  		text := scanner.Text()
  		if len(text) == 0 {
  			continue
  		}
  		if text[0] == '#' {
  			continue
  		}
  		ele := strings.Fields(text)
  		if len(ele) == 0 {
  			continue
  		}
  
  		// ok ele[0] is the path, the rest are (in our case) github usernames prefixed with @
  		for _, s := range ele[1:] {
  			if len(s) <= 1 {
  				continue
  			}
  			users[s[1:]] = struct{}{}
  		}
  	}
  	if err := scanner.Err(); err != nil {
  		return nil, err
  	}
  	u := []string{}
  	for k := range users {
  		if strings.HasPrefix(k, "@") {
  			k = k[1:]
  		}
  		u = append(u, k)
  	}
  	sort.Strings(u)
  	return u, nil
  }
  