github.com/google/cloudprober@v0.11.3/targets/statictargets.go (about)

     1  // Copyright 2021 The Cloudprober Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package targets
    16  
    17  import (
    18  	"fmt"
    19  	"net"
    20  	"strconv"
    21  	"strings"
    22  
    23  	"github.com/google/cloudprober/targets/endpoint"
    24  )
    25  
    26  func staticTargets(hosts string) (Targets, error) {
    27  	t, _ := baseTargets(nil, nil, nil)
    28  	sl := &staticLister{}
    29  
    30  	for _, host := range strings.Split(hosts, ",") {
    31  		host = strings.TrimSpace(host)
    32  
    33  		// Make sure there is no "/" in the host name. That typically happens
    34  		// when users accidentally add URLs in hostnames.
    35  		if strings.IndexByte(host, '/') >= 0 {
    36  			return nil, fmt.Errorf("invalid host (%s), contains '/'", host)
    37  		}
    38  
    39  		hostColonParts := strings.Split(host, ":")
    40  
    41  		// There is no colon in host name.
    42  		if len(hostColonParts) == 1 {
    43  			sl.list = append(sl.list, endpoint.Endpoint{Name: host})
    44  			continue
    45  		}
    46  
    47  		// There is only 1 colon, assume it is for the port. An IPv6 address will
    48  		// more than 1 colon.
    49  		if len(hostColonParts) == 2 {
    50  			portNum, err := strconv.Atoi(hostColonParts[1])
    51  			if err != nil {
    52  				return nil, fmt.Errorf("error parsing port(%s): %v", hostColonParts[1], err)
    53  			}
    54  			sl.list = append(sl.list, endpoint.Endpoint{Name: hostColonParts[0], Port: portNum})
    55  			continue
    56  		}
    57  
    58  		// More than 1 colon. It should include an IPv6 address.
    59  		// 1. Parses as an IP address. If that fails,
    60  		// 2. Parse for IPv6 and port.
    61  		if ip := net.ParseIP(host); ip != nil {
    62  			sl.list = append(sl.list, endpoint.Endpoint{Name: host})
    63  			continue
    64  		}
    65  		hostname, port, err := net.SplitHostPort(host)
    66  		if err != nil {
    67  			return nil, fmt.Errorf("error parsing host(%s) as hostport: %v", host, err)
    68  		}
    69  		portNum, err := strconv.Atoi(port)
    70  		if err != nil {
    71  			return nil, fmt.Errorf("error parsing port(%s): %v", port, err)
    72  		}
    73  		sl.list = append(sl.list, endpoint.Endpoint{Name: hostname, Port: portNum})
    74  	}
    75  
    76  	t.lister = sl
    77  	t.resolver = globalResolver
    78  	return t, nil
    79  }