github.com/timstclair/heapster@v0.20.0-alpha1/Godeps/_workspace/src/k8s.io/kubernetes/pkg/util/node/node.go (about)

     1  /*
     2  Copyright 2015 The Kubernetes Authors All rights reserved.
     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  package node
    18  
    19  import (
    20  	"fmt"
    21  	"net"
    22  	"os/exec"
    23  	"strings"
    24  
    25  	"github.com/golang/glog"
    26  	"k8s.io/kubernetes/pkg/api"
    27  )
    28  
    29  func GetHostname(hostnameOverride string) string {
    30  	hostname := hostnameOverride
    31  	if string(hostname) == "" {
    32  		nodename, err := exec.Command("uname", "-n").Output()
    33  		if err != nil {
    34  			glog.Fatalf("Couldn't determine hostname: %v", err)
    35  		}
    36  		hostname = string(nodename)
    37  	}
    38  	return strings.ToLower(strings.TrimSpace(hostname))
    39  }
    40  
    41  // GetNodeHostIP returns the provided node's IP, based on the priority:
    42  // 1. NodeInternalIP
    43  // 2. NodeExternalIP
    44  // 3. NodeLegacyHostIP
    45  func GetNodeHostIP(node *api.Node) (net.IP, error) {
    46  	addresses := node.Status.Addresses
    47  	addressMap := make(map[api.NodeAddressType][]api.NodeAddress)
    48  	for i := range addresses {
    49  		addressMap[addresses[i].Type] = append(addressMap[addresses[i].Type], addresses[i])
    50  	}
    51  	if addresses, ok := addressMap[api.NodeInternalIP]; ok {
    52  		return net.ParseIP(addresses[0].Address), nil
    53  	}
    54  	if addresses, ok := addressMap[api.NodeExternalIP]; ok {
    55  		return net.ParseIP(addresses[0].Address), nil
    56  	}
    57  	if addresses, ok := addressMap[api.NodeLegacyHostIP]; ok {
    58  		return net.ParseIP(addresses[0].Address), nil
    59  	}
    60  	return nil, fmt.Errorf("host IP unknown; known addresses: %v", addresses)
    61  }