moby/integration/network/bridge_test.go

package network

import (
	"context"
	"strings"
	"testing"
	"time"

	networktypes "github.com/docker/docker/api/types/network"
	"github.com/docker/docker/api/types/versions"
	ctr "github.com/docker/docker/integration/internal/container"
	"github.com/docker/docker/integration/internal/network"
	"gotest.tools/v3/assert"
	"gotest.tools/v3/skip"
)

func TestCreateWithMultiNetworks(t *testing.T) {
	skip.If(t, testEnv.DaemonInfo.OSType == "windows")
	skip.If(t, versions.LessThan(testEnv.DaemonAPIVersion(), "1.44"), "requires API v1.44")

	ctx := setupTest(t)
	apiClient := testEnv.APIClient()

	network.CreateNoError(ctx, t, apiClient, "testnet1")
	defer network.RemoveNoError(ctx, t, apiClient, "testnet1")

	network.CreateNoError(ctx, t, apiClient, "testnet2")
	defer network.RemoveNoError(ctx, t, apiClient, "testnet2")

	attachCtx, cancel := context.WithTimeout(ctx, 1*time.Second)
	defer cancel()
	res := ctr.RunAttach(attachCtx, t, apiClient,
		ctr.WithCmd("ip", "-o", "-4", "addr", "show"),
		ctr.WithNetworkMode("testnet1"),
		ctr.WithEndpointSettings("testnet1", &networktypes.EndpointSettings{}),
		ctr.WithEndpointSettings("testnet2", &networktypes.EndpointSettings{}))

	assert.Equal(t, res.ExitCode, 0)
	assert.Equal(t, res.Stderr.String(), "")

	// Only interfaces with an IPv4 address are printed by iproute2 when flag -4 is specified. Here, we should have two
	// interfaces for testnet1 and testnet2, plus lo.
	ifacesWithAddress := strings.Count(res.Stdout.String(), "\n")
	assert.Equal(t, ifacesWithAddress, 3)
}