github.com/containerd/nerdctl@v1.7.7/pkg/testutil/nettestutil/nettestutil.go (about)

     1  /*
     2     Copyright The containerd Authors.
     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 nettestutil
    18  
    19  import (
    20  	"crypto/rand"
    21  	"crypto/tls"
    22  	"fmt"
    23  	"net"
    24  	"net/http"
    25  	"time"
    26  
    27  	"github.com/containerd/errdefs"
    28  )
    29  
    30  func HTTPGet(urlStr string, attempts int, insecure bool) (*http.Response, error) {
    31  	var (
    32  		resp *http.Response
    33  		err  error
    34  	)
    35  	if attempts < 1 {
    36  		return nil, errdefs.ErrInvalidArgument
    37  	}
    38  	client := &http.Client{
    39  		Timeout: 3 * time.Second,
    40  		Transport: &http.Transport{
    41  			TLSClientConfig: &tls.Config{
    42  				InsecureSkipVerify: insecure,
    43  			},
    44  		},
    45  	}
    46  	for i := 0; i < attempts; i++ {
    47  		resp, err = client.Get(urlStr)
    48  		if err == nil {
    49  			return resp, nil
    50  		}
    51  		time.Sleep(100 * time.Millisecond)
    52  	}
    53  	return nil, fmt.Errorf("error after %d attempts: %w", attempts, err)
    54  }
    55  
    56  func NonLoopbackIPv4() (net.IP, error) {
    57  	addrs, err := net.InterfaceAddrs()
    58  	if err != nil {
    59  		return nil, err
    60  	}
    61  	for _, addr := range addrs {
    62  		ip, _, err := net.ParseCIDR(addr.String())
    63  		if err != nil {
    64  			continue
    65  		}
    66  		ipv4 := ip.To4()
    67  		if ipv4 == nil {
    68  			continue
    69  		}
    70  		if ipv4.IsLoopback() {
    71  			continue
    72  		}
    73  		return ipv4, nil
    74  	}
    75  	return nil, fmt.Errorf("non-loopback IPv4 address not found, attempted=%+v: %w", addrs, errdefs.ErrNotFound)
    76  }
    77  
    78  func GenerateMACAddress() (string, error) {
    79  	buf := make([]byte, 6)
    80  	if _, err := rand.Read(buf); err != nil {
    81  		return "", err
    82  	}
    83  	// make sure byte 0 (broadcast) of the first byte is not set
    84  	// and byte 1 (local) is set
    85  	buf[0] = buf[0]&254 | 2
    86  	return fmt.Sprintf("%02x:%02x:%02x:%02x:%02x:%02x", buf[0], buf[1], buf[2], buf[3], buf[4], buf[5]), nil
    87  }