github.com/SUSE/skuba@v1.4.17/pkg/skuba/actions/validate/validate.go (about)

     1  /*
     2   * Copyright (c) 2019 SUSE LLC.
     3   *
     4   * Licensed under the Apache License, Version 2.0 (the "License");
     5   * you may not use this file except in compliance with the License.
     6   * You may obtain a copy of the License at
     7   *
     8   *     http://www.apache.org/licenses/LICENSE-2.0
     9   *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   *
    16   */
    17  
    18  package validate
    19  
    20  import (
    21  	"fmt"
    22  	"regexp"
    23  
    24  	"github.com/SUSE/skuba/pkg/skuba"
    25  )
    26  
    27  var nodeNameRegex = regexp.MustCompile(`^[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*$`)
    28  
    29  // NodeName checks whether the node name is valid and acceptable for kubelet.
    30  func NodeName(nodename string) error {
    31  	if len(nodename) > skuba.MaxNodeNameLength {
    32  		return fmt.Errorf(
    33  			"invalid node name \"%s\": must be no more than %d characters",
    34  			nodename, skuba.MaxNodeNameLength)
    35  	}
    36  
    37  	if !nodeNameRegex.MatchString(nodename) {
    38  		return fmt.Errorf(
    39  			"invalid node name \"%s\": must consist of lower case alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character",
    40  			nodename)
    41  	}
    42  	return nil
    43  }