traefik/provider/docker.go
Emile Vauge bcc5f24c0f
Add GoSafe goroutine launch
Signed-off-by: Emile Vauge <emile@vauge.com>
2016-04-01 14:01:31 +02:00

269 lines
8.3 KiB
Go

package provider
import (
"errors"
"strconv"
"strings"
"text/template"
"time"
"github.com/BurntSushi/ty/fun"
log "github.com/Sirupsen/logrus"
"github.com/cenkalti/backoff"
"github.com/containous/traefik/safe"
"github.com/containous/traefik/types"
"github.com/fsouza/go-dockerclient"
)
// Docker holds configurations of the Docker provider.
type Docker struct {
BaseProvider `mapstructure:",squash"`
Endpoint string
Domain string
TLS *DockerTLS
}
// DockerTLS holds TLS specific configurations
type DockerTLS struct {
CA string
Cert string
Key string
InsecureSkipVerify bool
}
// Provide allows the provider to provide configurations to traefik
// using the given configuration channel.
func (provider *Docker) Provide(configurationChan chan<- types.ConfigMessage) error {
safe.Go(func() {
operation := func() error {
var dockerClient *docker.Client
var err error
if provider.TLS != nil {
dockerClient, err = docker.NewTLSClient(provider.Endpoint,
provider.TLS.Cert, provider.TLS.Key, provider.TLS.CA)
if err == nil {
dockerClient.TLSConfig.InsecureSkipVerify = provider.TLS.InsecureSkipVerify
}
} else {
dockerClient, err = docker.NewClient(provider.Endpoint)
}
if err != nil {
log.Errorf("Failed to create a client for docker, error: %s", err)
return err
}
err = dockerClient.Ping()
if err != nil {
log.Errorf("Docker connection error %+v", err)
return err
}
log.Debug("Docker connection established")
configuration := provider.loadDockerConfig(listContainers(dockerClient))
configurationChan <- types.ConfigMessage{
ProviderName: "docker",
Configuration: configuration,
}
if provider.Watch {
dockerEvents := make(chan *docker.APIEvents)
dockerClient.AddEventListener(dockerEvents)
log.Debug("Docker listening")
for {
event := <-dockerEvents
if event == nil {
return errors.New("Docker event nil")
// log.Fatalf("Docker connection error")
}
if event.Status == "start" || event.Status == "die" {
log.Debugf("Docker event receveived %+v", event)
configuration := provider.loadDockerConfig(listContainers(dockerClient))
if configuration != nil {
configurationChan <- types.ConfigMessage{
ProviderName: "docker",
Configuration: configuration,
}
}
}
}
}
return nil
}
notify := func(err error, time time.Duration) {
log.Errorf("Docker connection error %+v, retrying in %s", err, time)
}
err := backoff.RetryNotify(operation, backoff.NewExponentialBackOff(), notify)
if err != nil {
log.Fatalf("Cannot connect to docker server %+v", err)
}
})
return nil
}
func (provider *Docker) loadDockerConfig(containersInspected []docker.Container) *types.Configuration {
var DockerFuncMap = template.FuncMap{
"getBackend": provider.getBackend,
"getPort": provider.getPort,
"getWeight": provider.getWeight,
"getDomain": provider.getDomain,
"getProtocol": provider.getProtocol,
"getPassHostHeader": provider.getPassHostHeader,
"getEntryPoints": provider.getEntryPoints,
"getFrontendRule": provider.getFrontendRule,
"replace": replace,
}
// filter containers
filteredContainers := fun.Filter(containerFilter, containersInspected).([]docker.Container)
frontends := map[string][]docker.Container{}
for _, container := range filteredContainers {
frontends[provider.getFrontendName(container)] = append(frontends[provider.getFrontendName(container)], container)
}
templateObjects := struct {
Containers []docker.Container
Frontends map[string][]docker.Container
Domain string
}{
filteredContainers,
frontends,
provider.Domain,
}
configuration, err := provider.getConfiguration("templates/docker.tmpl", DockerFuncMap, templateObjects)
if err != nil {
log.Error(err)
}
return configuration
}
func containerFilter(container docker.Container) bool {
if len(container.NetworkSettings.Ports) == 0 {
log.Debugf("Filtering container without port %s", container.Name)
return false
}
_, err := strconv.Atoi(container.Config.Labels["traefik.port"])
if len(container.NetworkSettings.Ports) > 1 && err != nil {
log.Debugf("Filtering container with more than 1 port and no traefik.port label %s", container.Name)
return false
}
if container.Config.Labels["traefik.enable"] == "false" {
log.Debugf("Filtering disabled container %s", container.Name)
return false
}
return true
}
func (provider *Docker) getFrontendName(container docker.Container) 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 docker.Container) string {
// ⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠
// TODO: backwards compatibility with DEPRECATED rule.Value
if value, ok := container.Config.Labels["traefik.frontend.value"]; ok {
log.Warnf("Label traefik.frontend.value=%s is DEPRECATED (will be removed in v1.0.0), please refer to the rule label: https://github.com/containous/traefik/blob/master/docs/index.md#docker", value)
rule, _ := container.Config.Labels["traefik.frontend.rule"]
return rule + ":" + value
}
// ⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠
if label, err := getLabel(container, "traefik.frontend.rule"); err == nil {
return label
}
return "Host:" + getEscapedName(container.Name) + "." + provider.Domain
}
func (provider *Docker) getBackend(container docker.Container) string {
if label, err := getLabel(container, "traefik.backend"); err == nil {
return label
}
return normalize(container.Name)
}
func (provider *Docker) getPort(container docker.Container) 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 docker.Container) string {
if label, err := getLabel(container, "traefik.weight"); err == nil {
return label
}
return "1"
}
func (provider *Docker) getDomain(container docker.Container) string {
if label, err := getLabel(container, "traefik.domain"); err == nil {
return label
}
return provider.Domain
}
func (provider *Docker) getProtocol(container docker.Container) string {
if label, err := getLabel(container, "traefik.protocol"); err == nil {
return label
}
return "http"
}
func (provider *Docker) getPassHostHeader(container docker.Container) string {
if passHostHeader, err := getLabel(container, "traefik.frontend.passHostHeader"); err == nil {
return passHostHeader
}
return "false"
}
func (provider *Docker) getEntryPoints(container docker.Container) []string {
if entryPoints, err := getLabel(container, "traefik.frontend.entryPoints"); err == nil {
return strings.Split(entryPoints, ",")
}
return []string{}
}
func getLabel(container docker.Container, label string) (string, error) {
for key, value := range container.Config.Labels {
if key == label {
return value, nil
}
}
return "", errors.New("Label not found:" + label)
}
func getLabels(container docker.Container, 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(dockerClient *docker.Client) []docker.Container {
containerList, _ := dockerClient.ListContainers(docker.ListContainersOptions{})
containersInspected := []docker.Container{}
// get inspect containers
for _, container := range containerList {
containerInspected, _ := dockerClient.InspectContainer(container.ID)
containersInspected = append(containersInspected, *containerInspected)
}
return containersInspected
}