package main import ( "bytes" "errors" "strconv" "strings" "text/template" "time" "fmt" "github.com/BurntSushi/toml" "github.com/BurntSushi/ty/fun" log "github.com/Sirupsen/logrus" "github.com/cenkalti/backoff" "github.com/fsouza/go-dockerclient" ) type DockerProvider struct { Watch bool Endpoint string Filename string Domain string } func (provider *DockerProvider) Provide(configurationChan chan<- configMessage) error { if dockerClient, err := docker.NewClient(provider.Endpoint); err != nil { log.Errorf("Failed to create a client for docker, error: %s", err) return err } else { err := dockerClient.Ping() if err != nil { log.Errorf("Docker connection error %+v", err) return err } log.Debug("Docker connection established") if provider.Watch { dockerEvents := make(chan *docker.APIEvents) dockerClient.AddEventListener(dockerEvents) log.Debug("Docker listening") go func() { operation := func() error { 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(dockerClient) if configuration != nil { configurationChan <- configMessage{"docker", configuration} } } } } 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) } }() } configuration := provider.loadDockerConfig(dockerClient) configurationChan <- configMessage{"docker", configuration} } return nil } func (provider *DockerProvider) loadDockerConfig(dockerClient *docker.Client) *Configuration { var DockerFuncMap = template.FuncMap{ "getBackend": func(container docker.Container) string { if label, err := provider.getLabel(container, "traefik.backend"); err == nil { return label } return provider.getEscapedName(container.Name) }, "getPort": func(container docker.Container) string { if label, err := provider.getLabel(container, "traefik.port"); err == nil { return label } for key := range container.NetworkSettings.Ports { return key.Port() } return "" }, "getWeight": func(container docker.Container) string { if label, err := provider.getLabel(container, "traefik.weight"); err == nil { return label } return "0" }, "getDomain": func(container docker.Container) string { if label, err := provider.getLabel(container, "traefik.domain"); err == nil { return label } return provider.Domain }, "getProtocol": func(container docker.Container) string { if label, err := provider.getLabel(container, "traefik.protocol"); err == nil { return label } return "http" }, "getPassHostHeader": func(container docker.Container) string { if passHostHeader, err := provider.getLabel(container, "traefik.frontend.passHostHeader"); err == nil { return passHostHeader } return "false" }, "getFrontendValue": provider.GetFrontendValue, "getFrontendRule": provider.GetFrontendRule, "replace": func(s1 string, s2 string, s3 string) string { return strings.Replace(s3, s1, s2, -1) }, } configuration := new(Configuration) containerList, _ := dockerClient.ListContainers(docker.ListContainersOptions{}) containersInspected := []docker.Container{} frontends := map[string][]docker.Container{} // get inspect containers for _, container := range containerList { containerInspected, _ := dockerClient.InspectContainer(container.ID) containersInspected = append(containersInspected, *containerInspected) } // filter containers filteredContainers := fun.Filter(func(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 } if _, err := provider.getLabels(container, []string{"traefik.frontend.rule", "traefik.frontend.value"}); err != nil { log.Debugf("Filtering bad labeled container %s", container.Name) return false } return true }, containersInspected).([]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, } tmpl := template.New(provider.Filename).Funcs(DockerFuncMap) if len(provider.Filename) > 0 { _, err := tmpl.ParseFiles(provider.Filename) if err != nil { log.Error("Error reading file", err) return nil } } else { buf, err := Asset("templates/docker.tmpl") if err != nil { log.Error("Error reading file", err) } _, err = tmpl.Parse(string(buf)) if err != nil { log.Error("Error reading file", err) return nil } } var buffer bytes.Buffer err := tmpl.Execute(&buffer, templateObjects) if err != nil { log.Error("Error with docker template", err) return nil } if _, err := toml.Decode(buffer.String(), configuration); err != nil { log.Error("Error creating docker configuration ", err) return nil } return configuration } func (provider *DockerProvider) getFrontendName(container docker.Container) string { // Replace '.' with '-' in quoted keys because of this issue https://github.com/BurntSushi/toml/issues/78 frontendName := fmt.Sprintf("%s-%s", provider.GetFrontendRule(container), provider.GetFrontendValue(container)) return strings.Replace(frontendName, ".", "-", -1) } func (provider *DockerProvider) getEscapedName(name string) string { return strings.Replace(name, "/", "", -1) } func (provider *DockerProvider) 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 (provider *DockerProvider) getLabels(container docker.Container, labels []string) (map[string]string, error) { foundLabels := map[string]string{} for _, label := range labels { if foundLabel, err := provider.getLabel(container, label); err != nil { return nil, errors.New("Label not found: " + label) } else { foundLabels[label] = foundLabel } } return foundLabels, nil } func (provider *DockerProvider) GetFrontendValue(container docker.Container) string { if label, err := provider.getLabel(container, "traefik.frontend.value"); err == nil { return label } return provider.getEscapedName(container.Name) + "." + provider.Domain } func (provider *DockerProvider) GetFrontendRule(container docker.Container) string { if label, err := provider.getLabel(container, "traefik.frontend.rule"); err == nil { return label } return "Host" }