github.com/jandre/docker@v1.7.0/graph/tags/tags.go (about)

     1  package tags
     2  
     3  import (
     4  	"fmt"
     5  	"regexp"
     6  )
     7  
     8  const DEFAULTTAG = "latest"
     9  
    10  var (
    11  	//FIXME this regex also exists in registry/v2/regexp.go
    12  	validTagName = regexp.MustCompile(`^[\w][\w.-]{0,127}$`)
    13  )
    14  
    15  // ValidateTagName validates the name of a tag
    16  func ValidateTagName(name string) error {
    17  	if name == "" {
    18  		return fmt.Errorf("tag name can't be empty")
    19  	}
    20  	if !validTagName.MatchString(name) {
    21  		return fmt.Errorf("Illegal tag name (%s): only [A-Za-z0-9_.-] are allowed, minimum 1, maximum 128 in length", name)
    22  	}
    23  	return nil
    24  }