traefik/provider/docker.go
2017-02-03 09:46:27 +01:00

658 lines
20 KiB
Go

package provider
import (
"context"
"errors"
"math"
"net"
"net/http"
"strconv"
"strings"
"text/template"
"time"
"github.com/BurntSushi/ty/fun"
"github.com/cenk/backoff"
"github.com/containous/traefik/job"
"github.com/containous/traefik/log"
"github.com/containous/traefik/safe"
"github.com/containous/traefik/types"
"github.com/containous/traefik/version"
"github.com/docker/engine-api/client"
dockertypes "github.com/docker/engine-api/types"
dockercontainertypes "github.com/docker/engine-api/types/container"
eventtypes "github.com/docker/engine-api/types/events"
"github.com/docker/engine-api/types/filters"
"github.com/docker/engine-api/types/swarm"
swarmtypes "github.com/docker/engine-api/types/swarm"
"github.com/docker/go-connections/nat"
"github.com/docker/go-connections/sockets"
"github.com/vdemeester/docker-events"
)
const (
// DockerAPIVersion is a constant holding the version of the Docker API traefik will use
DockerAPIVersion string = "1.21"
// SwarmAPIVersion is a constant holding the version of the Docker API traefik will use
SwarmAPIVersion string = "1.24"
// SwarmDefaultWatchTime is the duration of the interval when polling docker
SwarmDefaultWatchTime = 15 * time.Second
)
var _ Provider = (*Docker)(nil)
// Docker holds configurations of the Docker provider.
type Docker struct {
BaseProvider `mapstructure:",squash"`
Endpoint string `description:"Docker server endpoint. Can be a tcp or a unix socket endpoint"`
Domain string `description:"Default domain used"`
TLS *ClientTLS `description:"Enable Docker TLS support"`
ExposedByDefault bool `description:"Expose containers by default"`
UseBindPortIP bool `description:"Use the ip address from the bound port, rather than from the inner network"`
SwarmMode bool `description:"Use Docker on Swarm Mode"`
}
// dockerData holds the need data to the Docker provider
type dockerData struct {
Name string
Labels map[string]string // List of labels set to container or service
NetworkSettings networkSettings
Health string
}
// NetworkSettings holds the networks data to the Docker provider
type networkSettings struct {
NetworkMode dockercontainertypes.NetworkMode
Ports nat.PortMap
Networks map[string]*networkData
}
// Network holds the network data to the Docker provider
type networkData struct {
Name string
Addr string
Port int
Protocol string
ID string
}
func (provider *Docker) createClient() (client.APIClient, error) {
var httpClient *http.Client
httpHeaders := map[string]string{
"User-Agent": "Traefik " + version.Version,
}
if provider.TLS != nil {
config, err := provider.TLS.CreateTLSConfig()
if err != nil {
return nil, err
}
tr := &http.Transport{
TLSClientConfig: config,
}
proto, addr, _, err := client.ParseHost(provider.Endpoint)
if err != nil {
return nil, err
}
sockets.ConfigureTransport(tr, proto, addr)
httpClient = &http.Client{
Transport: tr,
}
}
var version string
if provider.SwarmMode {
version = SwarmAPIVersion
} else {
version = DockerAPIVersion
}
return client.NewClient(provider.Endpoint, version, httpClient, httpHeaders)
}
// Provide allows the provider to provide configurations to traefik
// using the given configuration channel.
func (provider *Docker) Provide(configurationChan chan<- types.ConfigMessage, pool *safe.Pool, constraints types.Constraints) error {
provider.Constraints = append(provider.Constraints, constraints...)
// TODO register this routine in pool, and watch for stop channel
safe.Go(func() {
operation := func() error {
var err error
dockerClient, err := provider.createClient()
if err != nil {
log.Errorf("Failed to create a client for docker, error: %s", err)
return err
}
ctx := context.Background()
version, err := dockerClient.ServerVersion(ctx)
log.Debugf("Docker connection established with docker %s (API %s)", version.Version, version.APIVersion)
var dockerDataList []dockerData
if provider.SwarmMode {
dockerDataList, err = listServices(ctx, dockerClient)
if err != nil {
log.Errorf("Failed to list services for docker swarm mode, error %s", err)
return err
}
} else {
dockerDataList, err = listContainers(ctx, dockerClient)
if err != nil {
log.Errorf("Failed to list containers for docker, error %s", err)
return err
}
}
configuration := provider.loadDockerConfig(dockerDataList)
configurationChan <- types.ConfigMessage{
ProviderName: "docker",
Configuration: configuration,
}
if provider.Watch {
ctx, cancel := context.WithCancel(ctx)
if provider.SwarmMode {
// TODO: This need to be change. Linked to Swarm events docker/docker#23827
ticker := time.NewTicker(SwarmDefaultWatchTime)
pool.Go(func(stop chan bool) {
for {
select {
case <-ticker.C:
services, err := listServices(ctx, dockerClient)
if err != nil {
log.Errorf("Failed to list services for docker, error %s", err)
return
}
configuration := provider.loadDockerConfig(services)
if configuration != nil {
configurationChan <- types.ConfigMessage{
ProviderName: "docker",
Configuration: configuration,
}
}
case <-stop:
ticker.Stop()
cancel()
return
}
}
})
} else {
pool.Go(func(stop chan bool) {
for {
select {
case <-stop:
cancel()
return
}
}
})
f := filters.NewArgs()
f.Add("type", "container")
options := dockertypes.EventsOptions{
Filters: f,
}
eventHandler := events.NewHandler(events.ByAction)
startStopHandle := func(m eventtypes.Message) {
log.Debugf("Docker event received %+v", m)
containers, err := listContainers(ctx, dockerClient)
if err != nil {
log.Errorf("Failed to list containers for docker, error %s", err)
// Call cancel to get out of the monitor
cancel()
return
}
configuration := provider.loadDockerConfig(containers)
if configuration != nil {
configurationChan <- types.ConfigMessage{
ProviderName: "docker",
Configuration: configuration,
}
}
}
eventHandler.Handle("start", startStopHandle)
eventHandler.Handle("die", startStopHandle)
eventHandler.Handle("health_status: healthy", startStopHandle)
eventHandler.Handle("health_status: unhealthy", startStopHandle)
eventHandler.Handle("health_status: starting", startStopHandle)
errChan := events.MonitorWithHandler(ctx, dockerClient, options, eventHandler)
if err := <-errChan; err != nil {
return err
}
}
}
return nil
}
notify := func(err error, time time.Duration) {
log.Errorf("Docker connection error %+v, retrying in %s", err, time)
}
err := backoff.RetryNotify(safe.OperationWithRecover(operation), job.NewBackOff(backoff.NewExponentialBackOff()), notify)
if err != nil {
log.Errorf("Cannot connect to docker server %+v", err)
}
})
return nil
}
func (provider *Docker) loadDockerConfig(containersInspected []dockerData) *types.Configuration {
var DockerFuncMap = template.FuncMap{
"getBackend": provider.getBackend,
"getIPAddress": provider.getIPAddress,
"getPort": provider.getPort,
"getWeight": provider.getWeight,
"getDomain": provider.getDomain,
"getProtocol": provider.getProtocol,
"getPassHostHeader": provider.getPassHostHeader,
"getPriority": provider.getPriority,
"getEntryPoints": provider.getEntryPoints,
"getFrontendRule": provider.getFrontendRule,
"hasCircuitBreakerLabel": provider.hasCircuitBreakerLabel,
"getCircuitBreakerExpression": provider.getCircuitBreakerExpression,
"hasLoadBalancerLabel": provider.hasLoadBalancerLabel,
"getLoadBalancerMethod": provider.getLoadBalancerMethod,
"hasMaxConnLabels": provider.hasMaxConnLabels,
"getMaxConnAmount": provider.getMaxConnAmount,
"getMaxConnExtractorFunc": provider.getMaxConnExtractorFunc,
"getSticky": provider.getSticky,
}
// filter containers
filteredContainers := fun.Filter(func(container dockerData) bool {
return provider.containerFilter(container)
}, containersInspected).([]dockerData)
frontends := map[string][]dockerData{}
backends := map[string]dockerData{}
servers := map[string][]dockerData{}
for _, container := range filteredContainers {
frontendName := provider.getFrontendName(container)
frontends[frontendName] = append(frontends[frontendName], container)
backendName := provider.getBackend(container)
backends[backendName] = container
servers[backendName] = append(servers[backendName], container)
}
templateObjects := struct {
Containers []dockerData
Frontends map[string][]dockerData
Backends map[string]dockerData
Servers map[string][]dockerData
Domain string
}{
filteredContainers,
frontends,
backends,
servers,
provider.Domain,
}
configuration, err := provider.getConfiguration("templates/docker.tmpl", DockerFuncMap, templateObjects)
if err != nil {
log.Error(err)
}
return configuration
}
func (provider *Docker) hasCircuitBreakerLabel(container dockerData) bool {
if _, err := getLabel(container, "traefik.backend.circuitbreaker.expression"); err != nil {
return false
}
return true
}
func (provider *Docker) hasLoadBalancerLabel(container dockerData) bool {
_, errMethod := getLabel(container, "traefik.backend.loadbalancer.method")
_, errSticky := getLabel(container, "traefik.backend.loadbalancer.sticky")
if errMethod != nil && errSticky != nil {
return false
}
return true
}
func (provider *Docker) hasMaxConnLabels(container dockerData) bool {
if _, err := getLabel(container, "traefik.backend.maxconn.amount"); err != nil {
return false
}
if _, err := getLabel(container, "traefik.backend.maxconn.extractorfunc"); err != nil {
return false
}
return true
}
func (provider *Docker) getCircuitBreakerExpression(container dockerData) string {
if label, err := getLabel(container, "traefik.backend.circuitbreaker.expression"); err == nil {
return label
}
return "NetworkErrorRatio() > 1"
}
func (provider *Docker) getLoadBalancerMethod(container dockerData) string {
if label, err := getLabel(container, "traefik.backend.loadbalancer.method"); err == nil {
return label
}
return "wrr"
}
func (provider *Docker) getMaxConnAmount(container dockerData) int64 {
if label, err := getLabel(container, "traefik.backend.maxconn.amount"); err == nil {
i, errConv := strconv.ParseInt(label, 10, 64)
if errConv != nil {
log.Errorf("Unable to parse traefik.backend.maxconn.amount %s", label)
return math.MaxInt64
}
return i
}
return math.MaxInt64
}
func (provider *Docker) getMaxConnExtractorFunc(container dockerData) string {
if label, err := getLabel(container, "traefik.backend.maxconn.extractorfunc"); err == nil {
return label
}
return "request.host"
}
func (provider *Docker) containerFilter(container dockerData) bool {
_, err := strconv.Atoi(container.Labels["traefik.port"])
if len(container.NetworkSettings.Ports) == 0 && err != nil {
log.Debugf("Filtering container without port and no traefik.port label %s", container.Name)
return false
}
if !isContainerEnabled(container, provider.ExposedByDefault) {
log.Debugf("Filtering disabled container %s", container.Name)
return false
}
constraintTags := strings.Split(container.Labels["traefik.tags"], ",")
if ok, failingConstraint := provider.MatchConstraints(constraintTags); !ok {
if failingConstraint != nil {
log.Debugf("Container %v pruned by '%v' constraint", container.Name, failingConstraint.String())
}
return false
}
if container.Health != "" && container.Health != "healthy" {
log.Debugf("Filtering unhealthy or starting container %s", container.Name)
return false
}
return true
}
func (provider *Docker) getFrontendName(container dockerData) string {
// Replace '.' with '-' in quoted keys because of this issue https://github.com/BurntSushi/toml/issues/78
return normalize(provider.getFrontendRule(container))
}
// GetFrontendRule returns the frontend rule for the specified container, using
// it's label. It returns a default one (Host) if the label is not present.
func (provider *Docker) getFrontendRule(container dockerData) string {
if label, err := getLabel(container, "traefik.frontend.rule"); err == nil {
return label
}
return "Host:" + provider.getSubDomain(container.Name) + "." + provider.Domain
}
func (provider *Docker) getBackend(container dockerData) string {
if label, err := getLabel(container, "traefik.backend"); err == nil {
return normalize(label)
}
return normalize(container.Name)
}
func (provider *Docker) getIPAddress(container dockerData) string {
if label, err := getLabel(container, "traefik.docker.network"); err == nil && label != "" {
networkSettings := container.NetworkSettings
if networkSettings.Networks != nil {
network := networkSettings.Networks[label]
if network != nil {
return network.Addr
}
}
}
// If net==host, quick n' dirty, we return 127.0.0.1
// This will work locally, but will fail with swarm.
if "host" == container.NetworkSettings.NetworkMode {
return "127.0.0.1"
}
if provider.UseBindPortIP {
port := provider.getPort(container)
for netport, portBindings := range container.NetworkSettings.Ports {
if string(netport) == port+"/TCP" || string(netport) == port+"/UDP" {
for _, p := range portBindings {
return p.HostIP
}
}
}
}
for _, network := range container.NetworkSettings.Networks {
return network.Addr
}
return ""
}
func (provider *Docker) getPort(container dockerData) string {
if label, err := getLabel(container, "traefik.port"); err == nil {
return label
}
for key := range container.NetworkSettings.Ports {
return key.Port()
}
return ""
}
func (provider *Docker) getWeight(container dockerData) string {
if label, err := getLabel(container, "traefik.weight"); err == nil {
return label
}
return "0"
}
func (provider *Docker) getSticky(container dockerData) string {
if _, err := getLabel(container, "traefik.backend.loadbalancer.sticky"); err == nil {
return "true"
}
return "false"
}
func (provider *Docker) getDomain(container dockerData) string {
if label, err := getLabel(container, "traefik.domain"); err == nil {
return label
}
return provider.Domain
}
func (provider *Docker) getProtocol(container dockerData) string {
if label, err := getLabel(container, "traefik.protocol"); err == nil {
return label
}
return "http"
}
func (provider *Docker) getPassHostHeader(container dockerData) string {
if passHostHeader, err := getLabel(container, "traefik.frontend.passHostHeader"); err == nil {
return passHostHeader
}
return "true"
}
func (provider *Docker) getPriority(container dockerData) string {
if priority, err := getLabel(container, "traefik.frontend.priority"); err == nil {
return priority
}
return "0"
}
func (provider *Docker) getEntryPoints(container dockerData) []string {
if entryPoints, err := getLabel(container, "traefik.frontend.entryPoints"); err == nil {
return strings.Split(entryPoints, ",")
}
return []string{}
}
func isContainerEnabled(container dockerData, exposedByDefault bool) bool {
return exposedByDefault && container.Labels["traefik.enable"] != "false" || container.Labels["traefik.enable"] == "true"
}
func getLabel(container dockerData, label string) (string, error) {
for key, value := range container.Labels {
if key == label {
return value, nil
}
}
return "", errors.New("Label not found:" + label)
}
func getLabels(container dockerData, labels []string) (map[string]string, error) {
var globalErr error
foundLabels := map[string]string{}
for _, label := range labels {
foundLabel, err := getLabel(container, label)
// Error out only if one of them is defined.
if err != nil {
globalErr = errors.New("Label not found: " + label)
continue
}
foundLabels[label] = foundLabel
}
return foundLabels, globalErr
}
func listContainers(ctx context.Context, dockerClient client.ContainerAPIClient) ([]dockerData, error) {
containerList, err := dockerClient.ContainerList(ctx, dockertypes.ContainerListOptions{})
if err != nil {
return []dockerData{}, err
}
containersInspected := []dockerData{}
// get inspect containers
for _, container := range containerList {
containerInspected, err := dockerClient.ContainerInspect(ctx, container.ID)
if err != nil {
log.Warnf("Failed to inspect container %s, error: %s", container.ID, err)
} else {
dockerData := parseContainer(containerInspected)
containersInspected = append(containersInspected, dockerData)
}
}
return containersInspected, nil
}
func parseContainer(container dockertypes.ContainerJSON) dockerData {
dockerData := dockerData{
NetworkSettings: networkSettings{},
}
if container.ContainerJSONBase != nil {
dockerData.Name = container.ContainerJSONBase.Name
if container.ContainerJSONBase.HostConfig != nil {
dockerData.NetworkSettings.NetworkMode = container.ContainerJSONBase.HostConfig.NetworkMode
}
if container.State != nil && container.State.Health != nil {
dockerData.Health = container.State.Health.Status
}
}
if container.Config != nil && container.Config.Labels != nil {
dockerData.Labels = container.Config.Labels
}
if container.NetworkSettings != nil {
if container.NetworkSettings.Ports != nil {
dockerData.NetworkSettings.Ports = container.NetworkSettings.Ports
}
if container.NetworkSettings.Networks != nil {
dockerData.NetworkSettings.Networks = make(map[string]*networkData)
for name, containerNetwork := range container.NetworkSettings.Networks {
dockerData.NetworkSettings.Networks[name] = &networkData{
ID: containerNetwork.NetworkID,
Name: name,
Addr: containerNetwork.IPAddress,
}
}
}
}
return dockerData
}
// Escape beginning slash "/", convert all others to dash "-"
func (provider *Docker) getSubDomain(name string) string {
return strings.Replace(strings.TrimPrefix(name, "/"), "/", "-", -1)
}
func listServices(ctx context.Context, dockerClient client.APIClient) ([]dockerData, error) {
serviceList, err := dockerClient.ServiceList(ctx, dockertypes.ServiceListOptions{})
if err != nil {
return []dockerData{}, err
}
networkListArgs := filters.NewArgs()
networkListArgs.Add("driver", "overlay")
networkList, err := dockerClient.NetworkList(ctx, dockertypes.NetworkListOptions{Filters: networkListArgs})
networkMap := make(map[string]*dockertypes.NetworkResource)
if err != nil {
log.Debug("Failed to network inspect on client for docker, error: %s", err)
return []dockerData{}, err
}
for _, network := range networkList {
networkToAdd := network
networkMap[network.ID] = &networkToAdd
}
var dockerDataList []dockerData
for _, service := range serviceList {
dockerData := parseService(service, networkMap)
dockerDataList = append(dockerDataList, dockerData)
}
return dockerDataList, err
}
func parseService(service swarmtypes.Service, networkMap map[string]*dockertypes.NetworkResource) dockerData {
dockerData := dockerData{
Name: service.Spec.Annotations.Name,
Labels: service.Spec.Annotations.Labels,
NetworkSettings: networkSettings{},
}
if service.Spec.EndpointSpec != nil {
switch service.Spec.EndpointSpec.Mode {
case swarm.ResolutionModeDNSRR:
log.Debug("Ignored endpoint-mode not supported, service name: %s", dockerData.Name)
case swarm.ResolutionModeVIP:
dockerData.NetworkSettings.Networks = make(map[string]*networkData)
for _, virtualIP := range service.Endpoint.VirtualIPs {
networkService := networkMap[virtualIP.NetworkID]
if networkService != nil {
ip, _, _ := net.ParseCIDR(virtualIP.Addr)
network := &networkData{
Name: networkService.Name,
ID: virtualIP.NetworkID,
Addr: ip.String(),
}
dockerData.NetworkSettings.Networks[network.Name] = network
} else {
log.Debug("Network not found, id: %s", virtualIP.NetworkID)
}
}
}
}
return dockerData
}