open-nomad/client/driver/docker_test.go

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package driver
import (
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"fmt"
"io/ioutil"
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"math/rand"
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"os"
"os/exec"
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"path/filepath"
"reflect"
"runtime/debug"
"strings"
"testing"
"time"
docker "github.com/fsouza/go-dockerclient"
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"github.com/hashicorp/go-plugin"
"github.com/hashicorp/nomad/client/config"
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"github.com/hashicorp/nomad/client/driver/env"
cstructs "github.com/hashicorp/nomad/client/driver/structs"
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"github.com/hashicorp/nomad/helper/discover"
"github.com/hashicorp/nomad/nomad/structs"
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"github.com/hashicorp/nomad/testutil"
)
// dockerIsConnected checks to see if a docker daemon is available (local or remote)
func dockerIsConnected(t *testing.T) bool {
client, err := docker.NewClientFromEnv()
if err != nil {
return false
}
// Creating a client doesn't actually connect, so make sure we do something
// like call Version() on it.
env, err := client.Version()
if err != nil {
t.Logf("Failed to connect to docker daemon: %s", err)
return false
}
t.Logf("Successfully connected to docker daemon running version %s", env.Get("Version"))
return true
}
func dockerIsRemote(t *testing.T) bool {
client, err := docker.NewClientFromEnv()
if err != nil {
return false
}
// Technically this could be a local tcp socket but for testing purposes
// we'll just assume that tcp is only used for remote connections.
if client.Endpoint()[0:3] == "tcp" {
return true
}
return false
}
// Ports used by tests
var (
docker_reserved = 32768 + int(rand.Int31n(25000))
docker_dynamic = 32768 + int(rand.Int31n(25000))
)
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// Returns a task with a reserved and dynamic port. The ports are returned
// respectively.
func dockerTask() (*structs.Task, int, int) {
docker_reserved += 1
docker_dynamic += 1
return &structs.Task{
Name: "redis-demo",
Config: map[string]interface{}{
"image": "redis",
},
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LogConfig: &structs.LogConfig{
MaxFiles: 10,
MaxFileSizeMB: 10,
},
Resources: &structs.Resources{
MemoryMB: 256,
CPU: 512,
Networks: []*structs.NetworkResource{
&structs.NetworkResource{
IP: "127.0.0.1",
ReservedPorts: []structs.Port{{"main", docker_reserved}},
DynamicPorts: []structs.Port{{"REDIS", docker_dynamic}},
},
},
},
}, docker_reserved, docker_dynamic
}
// dockerSetup does all of the basic setup you need to get a running docker
// process up and running for testing. Use like:
//
// task := taskTemplate()
// // do custom task configuration
// client, handle, cleanup := dockerSetup(t, task)
// defer cleanup()
// // do test stuff
//
// If there is a problem during setup this function will abort or skip the test
// and indicate the reason.
func dockerSetup(t *testing.T, task *structs.Task) (*docker.Client, DriverHandle, func()) {
if !dockerIsConnected(t) {
t.SkipNow()
}
client, err := docker.NewClientFromEnv()
if err != nil {
t.Fatalf("Failed to initialize client: %s\nStack\n%s", err, debug.Stack())
}
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driverCtx, execCtx := testDriverContexts(task)
driver := NewDockerDriver(driverCtx)
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handle, err := driver.Start(execCtx, task)
if err != nil {
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execCtx.AllocDir.Destroy()
t.Fatalf("Failed to start driver: %s\nStack\n%s", err, debug.Stack())
}
if handle == nil {
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execCtx.AllocDir.Destroy()
t.Fatalf("handle is nil\nStack\n%s", debug.Stack())
}
cleanup := func() {
handle.Kill()
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execCtx.AllocDir.Destroy()
}
return client, handle, cleanup
}
func TestDockerDriver_Handle(t *testing.T) {
t.Parallel()
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bin, err := discover.NomadExecutable()
if err != nil {
t.Fatalf("got an err: %v", err)
}
f, _ := ioutil.TempFile(os.TempDir(), "")
defer f.Close()
defer os.Remove(f.Name())
pluginConfig := &plugin.ClientConfig{
Cmd: exec.Command(bin, "syslog", f.Name()),
}
exec, pluginClient, err := createExecutor(pluginConfig, os.Stdout, &config.Config{})
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if err != nil {
t.Fatalf("got an err: %v", err)
}
defer pluginClient.Kill()
h := &DockerHandle{
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version: "version",
imageID: "imageid",
executor: exec,
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pluginClient: pluginClient,
containerID: "containerid",
killTimeout: 5 * time.Nanosecond,
maxKillTimeout: 15 * time.Nanosecond,
doneCh: make(chan struct{}),
waitCh: make(chan *cstructs.WaitResult, 1),
}
actual := h.ID()
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expected := fmt.Sprintf("DOCKER:{\"Version\":\"version\",\"ImageID\":\"imageid\",\"ContainerID\":\"containerid\",\"KillTimeout\":5,\"MaxKillTimeout\":15,\"PluginConfig\":{\"Pid\":%d,\"AddrNet\":\"unix\",\"AddrName\":\"%s\"}}",
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pluginClient.ReattachConfig().Pid, pluginClient.ReattachConfig().Addr.String())
if actual != expected {
t.Errorf("Expected `%s`, found `%s`", expected, actual)
}
}
// This test should always pass, even if docker daemon is not available
func TestDockerDriver_Fingerprint(t *testing.T) {
t.Parallel()
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driverCtx, _ := testDriverContexts(&structs.Task{Name: "foo"})
d := NewDockerDriver(driverCtx)
node := &structs.Node{
Attributes: make(map[string]string),
}
apply, err := d.Fingerprint(&config.Config{}, node)
if err != nil {
t.Fatalf("err: %v", err)
}
if apply != dockerIsConnected(t) {
t.Fatalf("Fingerprinter should detect when docker is available")
}
if node.Attributes["driver.docker"] != "1" {
t.Log("Docker daemon not available. The remainder of the docker tests will be skipped.")
}
t.Logf("Found docker version %s", node.Attributes["driver.docker.version"])
}
func TestDockerDriver_StartOpen_Wait(t *testing.T) {
t.Parallel()
if !dockerIsConnected(t) {
t.SkipNow()
}
task := &structs.Task{
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Name: "redis-demo",
Config: map[string]interface{}{
"image": "redis",
},
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LogConfig: &structs.LogConfig{
MaxFiles: 10,
MaxFileSizeMB: 10,
},
Resources: basicResources,
}
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driverCtx, execCtx := testDriverContexts(task)
defer execCtx.AllocDir.Destroy()
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d := NewDockerDriver(driverCtx)
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handle, err := d.Start(execCtx, task)
if err != nil {
t.Fatalf("err: %v", err)
}
if handle == nil {
t.Fatalf("missing handle")
}
defer handle.Kill()
// Attempt to open
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handle2, err := d.Open(execCtx, handle.ID())
if err != nil {
t.Fatalf("err: %v", err)
}
if handle2 == nil {
t.Fatalf("missing handle")
}
}
func TestDockerDriver_Start_Wait(t *testing.T) {
t.Parallel()
task := &structs.Task{
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Name: "redis-demo",
Config: map[string]interface{}{
"image": "redis",
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"command": "redis-server",
"args": []string{"-v"},
},
Resources: &structs.Resources{
MemoryMB: 256,
CPU: 512,
},
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LogConfig: &structs.LogConfig{
MaxFiles: 10,
MaxFileSizeMB: 10,
},
}
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_, handle, cleanup := dockerSetup(t, task)
defer cleanup()
// Update should be a no-op
err := handle.Update(task)
if err != nil {
t.Fatalf("err: %v", err)
}
select {
case res := <-handle.WaitCh():
if !res.Successful() {
t.Fatalf("err: %v", res)
}
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case <-time.After(time.Duration(testutil.TestMultiplier()*5) * time.Second):
t.Fatalf("timeout")
}
}
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func TestDockerDriver_Start_Wait_AllocDir(t *testing.T) {
t.Parallel()
// This test requires that the alloc dir be mounted into docker as a volume.
// Because this cannot happen when docker is run remotely, e.g. when running
// docker in a VM, we skip this when we detect Docker is being run remotely.
if !dockerIsConnected(t) || dockerIsRemote(t) {
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t.SkipNow()
}
exp := []byte{'w', 'i', 'n'}
file := "output.txt"
task := &structs.Task{
Name: "redis-demo",
Config: map[string]interface{}{
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"image": "redis",
"command": "/bin/bash",
"args": []string{
"-c",
fmt.Sprintf(`sleep 1; echo -n %s > $%s/%s`,
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string(exp), env.AllocDir, file),
},
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},
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LogConfig: &structs.LogConfig{
MaxFiles: 10,
MaxFileSizeMB: 10,
},
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Resources: &structs.Resources{
MemoryMB: 256,
CPU: 512,
},
}
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driverCtx, execCtx := testDriverContexts(task)
defer execCtx.AllocDir.Destroy()
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d := NewDockerDriver(driverCtx)
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handle, err := d.Start(execCtx, task)
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if err != nil {
t.Fatalf("err: %v", err)
}
if handle == nil {
t.Fatalf("missing handle")
}
defer handle.Kill()
select {
case res := <-handle.WaitCh():
if !res.Successful() {
t.Fatalf("err: %v", res)
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}
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case <-time.After(time.Duration(testutil.TestMultiplier()*5) * time.Second):
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t.Fatalf("timeout")
}
// Check that data was written to the shared alloc directory.
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outputFile := filepath.Join(execCtx.AllocDir.SharedDir, file)
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act, err := ioutil.ReadFile(outputFile)
if err != nil {
t.Fatalf("Couldn't read expected output: %v", err)
}
if !reflect.DeepEqual(act, exp) {
t.Fatalf("Command outputted %v; want %v", act, exp)
}
}
func TestDockerDriver_Start_Kill_Wait(t *testing.T) {
t.Parallel()
task := &structs.Task{
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Name: "redis-demo",
Config: map[string]interface{}{
"image": "redis",
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"command": "/bin/sleep",
"args": []string{"10"},
},
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LogConfig: &structs.LogConfig{
MaxFiles: 10,
MaxFileSizeMB: 10,
},
Resources: basicResources,
}
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_, handle, cleanup := dockerSetup(t, task)
defer cleanup()
go func() {
time.Sleep(100 * time.Millisecond)
err := handle.Kill()
if err != nil {
t.Fatalf("err: %v", err)
}
}()
select {
case res := <-handle.WaitCh():
if res.Successful() {
t.Fatalf("should err: %v", res)
}
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case <-time.After(time.Duration(testutil.TestMultiplier()*10) * time.Second):
t.Fatalf("timeout")
}
}
func TestDocker_StartN(t *testing.T) {
t.Parallel()
if !dockerIsConnected(t) {
t.SkipNow()
}
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task1, _, _ := dockerTask()
task2, _, _ := dockerTask()
task3, _, _ := dockerTask()
taskList := []*structs.Task{task1, task2, task3}
handles := make([]DriverHandle, len(taskList))
t.Logf("==> Starting %d tasks", len(taskList))
// Let's spin up a bunch of things
var err error
for idx, task := range taskList {
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driverCtx, execCtx := testDriverContexts(task)
defer execCtx.AllocDir.Destroy()
d := NewDockerDriver(driverCtx)
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handles[idx], err = d.Start(execCtx, task)
if err != nil {
t.Errorf("Failed starting task #%d: %s", idx+1, err)
}
}
t.Log("==> All tasks are started. Terminating...")
for idx, handle := range handles {
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if handle == nil {
t.Errorf("Bad handle for task #%d", idx+1)
continue
}
err := handle.Kill()
if err != nil {
t.Errorf("Failed stopping task #%d: %s", idx+1, err)
}
}
t.Log("==> Test complete!")
}
func TestDocker_StartNVersions(t *testing.T) {
t.Parallel()
if !dockerIsConnected(t) {
t.SkipNow()
}
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task1, _, _ := dockerTask()
task1.Config["image"] = "redis"
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task2, _, _ := dockerTask()
task2.Config["image"] = "redis:latest"
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task3, _, _ := dockerTask()
task3.Config["image"] = "redis:3.0"
taskList := []*structs.Task{task1, task2, task3}
handles := make([]DriverHandle, len(taskList))
t.Logf("==> Starting %d tasks", len(taskList))
// Let's spin up a bunch of things
var err error
for idx, task := range taskList {
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driverCtx, execCtx := testDriverContexts(task)
defer execCtx.AllocDir.Destroy()
d := NewDockerDriver(driverCtx)
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handles[idx], err = d.Start(execCtx, task)
if err != nil {
t.Errorf("Failed starting task #%d: %s", idx+1, err)
}
}
t.Log("==> All tasks are started. Terminating...")
for idx, handle := range handles {
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if handle == nil {
t.Errorf("Bad handle for task #%d", idx+1)
continue
}
err := handle.Kill()
if err != nil {
t.Errorf("Failed stopping task #%d: %s", idx+1, err)
}
}
t.Log("==> Test complete!")
}
func TestDockerHostNet(t *testing.T) {
t.Parallel()
expected := "host"
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task := &structs.Task{
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Name: "redis-demo",
Config: map[string]interface{}{
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"image": "redis",
"network_mode": expected,
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},
Resources: &structs.Resources{
MemoryMB: 256,
CPU: 512,
},
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LogConfig: &structs.LogConfig{
MaxFiles: 10,
MaxFileSizeMB: 10,
},
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}
client, handle, cleanup := dockerSetup(t, task)
defer cleanup()
container, err := client.InspectContainer(handle.(*DockerHandle).ContainerID())
if err != nil {
t.Fatalf("err: %v", err)
}
actual := container.HostConfig.NetworkMode
if actual != expected {
t.Errorf("DNS Network mode doesn't match.\nExpected:\n%s\nGot:\n%s\n", expected, actual)
}
}
func TestDockerLabels(t *testing.T) {
t.Parallel()
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task, _, _ := dockerTask()
task.Config["labels"] = []map[string]string{
map[string]string{
"label1": "value1",
"label2": "value2",
},
}
client, handle, cleanup := dockerSetup(t, task)
defer cleanup()
container, err := client.InspectContainer(handle.(*DockerHandle).ContainerID())
if err != nil {
t.Fatalf("err: %v", err)
}
if want, got := 2, len(container.Config.Labels); want != got {
t.Errorf("Wrong labels count for docker job. Expect: %d, got: %d", want, got)
}
if want, got := "value1", container.Config.Labels["label1"]; want != got {
t.Errorf("Wrong label value docker job. Expect: %s, got: %s", want, got)
}
}
func TestDockerDNS(t *testing.T) {
t.Parallel()
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task, _, _ := dockerTask()
task.Config["dns_servers"] = []string{"8.8.8.8", "8.8.4.4"}
task.Config["dns_search_domains"] = []string{"example.com", "example.org", "example.net"}
client, handle, cleanup := dockerSetup(t, task)
defer cleanup()
container, err := client.InspectContainer(handle.(*DockerHandle).ContainerID())
if err != nil {
t.Fatalf("err: %v", err)
}
if !reflect.DeepEqual(task.Config["dns_servers"], container.HostConfig.DNS) {
t.Errorf("DNS Servers don't match.\nExpected:\n%s\nGot:\n%s\n", task.Config["dns_servers"], container.HostConfig.DNS)
}
if !reflect.DeepEqual(task.Config["dns_search_domains"], container.HostConfig.DNSSearch) {
t.Errorf("DNS Servers don't match.\nExpected:\n%s\nGot:\n%s\n", task.Config["dns_search_domains"], container.HostConfig.DNSSearch)
}
}
func inSlice(needle string, haystack []string) bool {
for _, h := range haystack {
if h == needle {
return true
}
}
return false
}
func TestDockerPortsNoMap(t *testing.T) {
t.Parallel()
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task, res, dyn := dockerTask()
client, handle, cleanup := dockerSetup(t, task)
defer cleanup()
container, err := client.InspectContainer(handle.(*DockerHandle).ContainerID())
if err != nil {
t.Fatalf("err: %v", err)
}
// Verify that the correct ports are EXPOSED
expectedExposedPorts := map[docker.Port]struct{}{
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docker.Port(fmt.Sprintf("%d/tcp", res)): struct{}{},
docker.Port(fmt.Sprintf("%d/udp", res)): struct{}{},
docker.Port(fmt.Sprintf("%d/tcp", dyn)): struct{}{},
docker.Port(fmt.Sprintf("%d/udp", dyn)): struct{}{},
// This one comes from the redis container
docker.Port("6379/tcp"): struct{}{},
}
if !reflect.DeepEqual(container.Config.ExposedPorts, expectedExposedPorts) {
t.Errorf("Exposed ports don't match.\nExpected:\n%s\nGot:\n%s\n", expectedExposedPorts, container.Config.ExposedPorts)
}
// Verify that the correct ports are FORWARDED
expectedPortBindings := map[docker.Port][]docker.PortBinding{
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docker.Port(fmt.Sprintf("%d/tcp", res)): []docker.PortBinding{docker.PortBinding{HostIP: "127.0.0.1", HostPort: fmt.Sprintf("%d", res)}},
docker.Port(fmt.Sprintf("%d/udp", res)): []docker.PortBinding{docker.PortBinding{HostIP: "127.0.0.1", HostPort: fmt.Sprintf("%d", res)}},
docker.Port(fmt.Sprintf("%d/tcp", dyn)): []docker.PortBinding{docker.PortBinding{HostIP: "127.0.0.1", HostPort: fmt.Sprintf("%d", dyn)}},
docker.Port(fmt.Sprintf("%d/udp", dyn)): []docker.PortBinding{docker.PortBinding{HostIP: "127.0.0.1", HostPort: fmt.Sprintf("%d", dyn)}},
}
if !reflect.DeepEqual(container.HostConfig.PortBindings, expectedPortBindings) {
t.Errorf("Forwarded ports don't match.\nExpected:\n%s\nGot:\n%s\n", expectedPortBindings, container.HostConfig.PortBindings)
}
expectedEnvironment := map[string]string{
"NOMAD_ADDR_main": fmt.Sprintf("127.0.0.1:%d", res),
"NOMAD_ADDR_REDIS": fmt.Sprintf("127.0.0.1:%d", dyn),
}
for key, val := range expectedEnvironment {
search := fmt.Sprintf("%s=%s", key, val)
if !inSlice(search, container.Config.Env) {
t.Errorf("Expected to find %s in container environment: %+v", search, container.Config.Env)
}
}
}
func TestDockerPortsMapping(t *testing.T) {
t.Parallel()
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task, res, dyn := dockerTask()
task.Config["port_map"] = []map[string]string{
map[string]string{
"main": "8080",
"REDIS": "6379",
},
}
client, handle, cleanup := dockerSetup(t, task)
defer cleanup()
container, err := client.InspectContainer(handle.(*DockerHandle).ContainerID())
if err != nil {
t.Fatalf("err: %v", err)
}
// Verify that the correct ports are EXPOSED
expectedExposedPorts := map[docker.Port]struct{}{
docker.Port("8080/tcp"): struct{}{},
docker.Port("8080/udp"): struct{}{},
docker.Port("6379/tcp"): struct{}{},
docker.Port("6379/udp"): struct{}{},
}
if !reflect.DeepEqual(container.Config.ExposedPorts, expectedExposedPorts) {
t.Errorf("Exposed ports don't match.\nExpected:\n%s\nGot:\n%s\n", expectedExposedPorts, container.Config.ExposedPorts)
}
// Verify that the correct ports are FORWARDED
expectedPortBindings := map[docker.Port][]docker.PortBinding{
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docker.Port("8080/tcp"): []docker.PortBinding{docker.PortBinding{HostIP: "127.0.0.1", HostPort: fmt.Sprintf("%d", res)}},
docker.Port("8080/udp"): []docker.PortBinding{docker.PortBinding{HostIP: "127.0.0.1", HostPort: fmt.Sprintf("%d", res)}},
docker.Port("6379/tcp"): []docker.PortBinding{docker.PortBinding{HostIP: "127.0.0.1", HostPort: fmt.Sprintf("%d", dyn)}},
docker.Port("6379/udp"): []docker.PortBinding{docker.PortBinding{HostIP: "127.0.0.1", HostPort: fmt.Sprintf("%d", dyn)}},
}
if !reflect.DeepEqual(container.HostConfig.PortBindings, expectedPortBindings) {
t.Errorf("Forwarded ports don't match.\nExpected:\n%s\nGot:\n%s\n", expectedPortBindings, container.HostConfig.PortBindings)
}
expectedEnvironment := map[string]string{
"NOMAD_ADDR_main": "127.0.0.1:8080",
"NOMAD_ADDR_REDIS": "127.0.0.1:6379",
"NOMAD_HOST_PORT_main": "8080",
}
for key, val := range expectedEnvironment {
search := fmt.Sprintf("%s=%s", key, val)
if !inSlice(search, container.Config.Env) {
t.Errorf("Expected to find %s in container environment: %+v", search, container.Config.Env)
}
}
}
func TestDockerUser(t *testing.T) {
t.Parallel()
task := &structs.Task{
Name: "redis-demo",
User: "alice",
Config: map[string]interface{}{
"image": "redis",
"command": "sleep",
"args": []string{"10000"},
},
Resources: &structs.Resources{
MemoryMB: 256,
CPU: 512,
},
LogConfig: &structs.LogConfig{
MaxFiles: 10,
MaxFileSizeMB: 10,
},
}
if !dockerIsConnected(t) {
t.SkipNow()
}
driverCtx, execCtx := testDriverContexts(task)
driver := NewDockerDriver(driverCtx)
defer execCtx.AllocDir.Destroy()
// It should fail because the user "alice" does not exist on the given
// image.
handle, err := driver.Start(execCtx, task)
if err == nil {
handle.Kill()
t.Fatalf("Should've failed")
}
msg := "System error: Unable to find user alice"
if !strings.Contains(err.Error(), msg) {
t.Fatalf("Expecting '%v' in '%v'", msg, err)
}
}