run_network_test.go

/*
   Copyright The containerd Authors.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

package main

import (
	"fmt"
	"io/ioutil"
	"net"
	"net/http"
	"strings"
	"testing"
	"time"

	"github.com/containerd/containerd/errdefs"
	"github.com/containerd/nerdctl/pkg/testutil"
	"github.com/pkg/errors"
	"gotest.tools/v3/assert"
)

// TestRunInternetConnectivity tests Internet connectivity with `apk update`
func TestRunInternetConnectivity(t *testing.T) {
	base := testutil.NewBase(t)
	customNet := "customnet1"
	base.Cmd("network", "create", customNet).AssertOK()
	defer base.Cmd("network", "rm", customNet).Run()

	type testCase struct {
		args []string
	}
	testCases := []testCase{
		{
			args: []string{"--net", "bridge"},
		},
		{
			args: []string{"--net", customNet},
		},
		{
			args: []string{"--net", "host"},
		},
	}
	for _, tc := range testCases {
		tc := tc // IMPORTANT
		name := "default"
		if len(tc.args) > 0 {
			name = strings.Join(tc.args, "_")
		}
		t.Run(name, func(t *testing.T) {
			args := []string{"run", "--rm"}
			args = append(args, tc.args...)
			args = append(args, testutil.AlpineImage, "apk", "update")
			cmd := base.Cmd(args...)
			cmd.AssertOut("OK")
		})
	}
}

// TestRunHostLookup tests hostname lookup
func TestRunHostLookup(t *testing.T) {
	base := testutil.NewBase(t)
	// key: container name, val: network name
	m := map[string]string{
		"c0-in-n0":     "n0",
		"c1-in-n0":     "n0",
		"c2-in-n1":     "n1",
		"c3-in-bridge": "bridge",
	}
	customNets := valuesOfMapStringString(m)
	defer func() {
		for name := range m {
			base.Cmd("rm", "-f", name).Run()
		}
		for netName := range customNets {
			if netName == "bridge" {
				continue
			}
			base.Cmd("network", "rm", netName).Run()
		}
	}()

	// Create networks
	for netName := range customNets {
		if netName == "bridge" {
			continue
		}
		base.Cmd("network", "create", netName).AssertOK()
	}

	// Create nginx containers
	for name, netName := range m {
		base.Cmd("run",
			"-d",
			"--name", name,
			"--hostname", name+"-foobar",
			"--net", netName,
			testutil.NginxAlpineImage,
		).AssertOK()
	}

	testWget := func(srcContainer, targetHostname string, expected bool) {
		t.Logf("resolving %q in container %q (should success: %+v)", targetHostname, srcContainer, expected)
		cmd := base.Cmd("exec", srcContainer, "wget", "-qO-", "http://"+targetHostname)
		if expected {
			cmd.AssertOut(testutil.NginxAlpineIndexHTMLSnippet)
		} else {
			cmd.AssertFail()
		}
	}

	// Tests begin
	testWget("c0-in-n0", "c1-in-n0", true)
	testWget("c0-in-n0", "c1-in-n0.n0", true)
	testWget("c0-in-n0", "c1-in-n0-foobar", true)
	testWget("c0-in-n0", "c1-in-n0-foobar.n0", true)
	testWget("c0-in-n0", "c2-in-n1", false)
	testWget("c0-in-n0", "c2-in-n1.n1", false)
	testWget("c0-in-n0", "c3-in-bridge", false)
	testWget("c1-in-n0", "c0-in-n0", true)
	testWget("c1-in-n0", "c0-in-n0.n0", true)
	testWget("c1-in-n0", "c0-in-n0-foobar", true)
	testWget("c1-in-n0", "c0-in-n0-foobar.n0", true)
}

func valuesOfMapStringString(m map[string]string) map[string]struct{} {
	res := make(map[string]struct{})
	for _, v := range m {
		res[v] = struct{}{}
	}
	return res
}

func TestRunPort(t *testing.T) {
	hostIP, err := getNonLoopbackIPv4()
	assert.NilError(t, err)
	type testCase struct {
		listenIP  net.IP
		connectIP net.IP
		port      int
		err       string
	}
	lo := net.ParseIP("127.0.0.1")
	zeroIP := net.ParseIP("0.0.0.0")
	testCases := []testCase{
		{
			listenIP:  lo,
			connectIP: lo,
			port:      8080,
		},
		{
			// for https://github.com/containerd/nerdctl/issues/88
			listenIP:  hostIP,
			connectIP: hostIP,
			port:      8080,
		},
		{
			listenIP:  hostIP,
			connectIP: lo,
			port:      8080,
			err:       "connection refused",
		},
		{
			listenIP:  lo,
			connectIP: hostIP,
			port:      8080,
			err:       "connection refused",
		},
		{
			listenIP:  zeroIP,
			connectIP: lo,
			port:      8080,
		},
		{
			listenIP:  zeroIP,
			connectIP: hostIP,
			port:      8080,
		},
	}
	for i, tc := range testCases {
		i := i
		tc := tc
		tcName := fmt.Sprintf("%+v", tc)
		t.Run(tcName, func(t *testing.T) {
			testContainerName := fmt.Sprintf("nerdctl-test-nginx-%d", i)
			base := testutil.NewBase(t)
			defer base.Cmd("rm", "-f", testContainerName).Run()
			pFlag := fmt.Sprintf("%s:%d:80", tc.listenIP.String(), tc.port)
			connectURL := fmt.Sprintf("http://%s:%d", tc.connectIP.String(), tc.port)
			t.Logf("pFlag=%q, connectURL=%q", pFlag, connectURL)
			base.Cmd("run", "-d",
				"--name", testContainerName,
				"-p", pFlag,
				testutil.NginxAlpineImage).AssertOK()

			resp, err := httpGet(connectURL, 30)
			if tc.err != "" {
				assert.ErrorContains(t, err, tc.err)
				return
			}
			assert.NilError(t, err)
			respBody, err := ioutil.ReadAll(resp.Body)
			assert.NilError(t, err)
			assert.Assert(t, strings.Contains(string(respBody), testutil.NginxAlpineIndexHTMLSnippet))
		})
	}
}

func httpGet(urlStr string, attempts int) (*http.Response, error) {
	var (
		resp *http.Response
		err  error
	)
	if attempts < 1 {
		return nil, errdefs.ErrInvalidArgument
	}
	client := &http.Client{
		Timeout: 3 * time.Second,
	}
	for i := 0; i < attempts; i++ {
		resp, err = client.Get(urlStr)
		if err == nil {
			return resp, nil
		}
		time.Sleep(100 * time.Millisecond)
	}
	return nil, errors.Wrapf(err, "error after %d attempts", attempts)
}