traefik/provider/marathon/marathon.go
Timo Reimann 099d605aed Check for explicitly defined Marathon port first.
Previously, we did the check too late resulting in the traefik.port
label not being effective.

The change comes with additional refactorings in production and tests.
2017-04-25 23:18:30 +02:00

546 lines
17 KiB
Go

package marathon
import (
"errors"
"fmt"
"math"
"net"
"net/http"
"net/url"
"strconv"
"strings"
"text/template"
"time"
"github.com/BurntSushi/ty/fun"
"github.com/cenk/backoff"
"github.com/containous/flaeg"
"github.com/containous/traefik/job"
"github.com/containous/traefik/log"
"github.com/containous/traefik/provider"
"github.com/containous/traefik/safe"
"github.com/containous/traefik/types"
"github.com/gambol99/go-marathon"
)
const (
labelPort = "traefik.port"
labelPortIndex = "traefik.portIndex"
)
var _ provider.Provider = (*Provider)(nil)
// Provider holds configuration of the provider.
type Provider struct {
provider.BaseProvider
Endpoint string `description:"Marathon server endpoint. You can also specify multiple endpoint for Marathon"`
Domain string `description:"Default domain used"`
ExposedByDefault bool `description:"Expose Marathon apps by default"`
GroupsAsSubDomains bool `description:"Convert Marathon groups to subdomains"`
DCOSToken string `description:"DCOSToken for DCOS environment, This will override the Authorization header"`
MarathonLBCompatibility bool `description:"Add compatibility with marathon-lb labels"`
TLS *provider.ClientTLS `description:"Enable Docker TLS support"`
DialerTimeout flaeg.Duration `description:"Set a non-default connection timeout for Marathon"`
KeepAlive flaeg.Duration `description:"Set a non-default TCP Keep Alive time in seconds"`
Basic *Basic
marathonClient marathon.Marathon
}
// Basic holds basic authentication specific configurations
type Basic struct {
HTTPBasicAuthUser string
HTTPBasicPassword string
}
type lightMarathonClient interface {
AllTasks(v url.Values) (*marathon.Tasks, error)
Applications(url.Values) (*marathon.Applications, error)
}
// Provide allows the marathon provider to provide configurations to traefik
// using the given configuration channel.
func (p *Provider) Provide(configurationChan chan<- types.ConfigMessage, pool *safe.Pool, constraints types.Constraints) error {
p.Constraints = append(p.Constraints, constraints...)
operation := func() error {
config := marathon.NewDefaultConfig()
config.URL = p.Endpoint
config.EventsTransport = marathon.EventsTransportSSE
if p.Basic != nil {
config.HTTPBasicAuthUser = p.Basic.HTTPBasicAuthUser
config.HTTPBasicPassword = p.Basic.HTTPBasicPassword
}
if len(p.DCOSToken) > 0 {
config.DCOSToken = p.DCOSToken
}
TLSConfig, err := p.TLS.CreateTLSConfig()
if err != nil {
return err
}
config.HTTPClient = &http.Client{
Transport: &http.Transport{
DialContext: (&net.Dialer{
KeepAlive: time.Duration(p.KeepAlive),
Timeout: time.Duration(p.DialerTimeout),
}).DialContext,
TLSClientConfig: TLSConfig,
},
}
client, err := marathon.NewClient(config)
if err != nil {
log.Errorf("Failed to create a client for marathon, error: %s", err)
return err
}
p.marathonClient = client
if p.Watch {
update, err := client.AddEventsListener(marathon.EventIDApplications)
if err != nil {
log.Errorf("Failed to register for events, %s", err)
return err
}
pool.Go(func(stop chan bool) {
defer close(update)
for {
select {
case <-stop:
return
case event := <-update:
log.Debug("Provider event receveived", event)
configuration := p.loadMarathonConfig()
if configuration != nil {
configurationChan <- types.ConfigMessage{
ProviderName: "marathon",
Configuration: configuration,
}
}
}
}
})
}
configuration := p.loadMarathonConfig()
configurationChan <- types.ConfigMessage{
ProviderName: "marathon",
Configuration: configuration,
}
return nil
}
notify := func(err error, time time.Duration) {
log.Errorf("Provider 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 Provider server %+v", err)
}
return nil
}
func (p *Provider) loadMarathonConfig() *types.Configuration {
var MarathonFuncMap = template.FuncMap{
"getBackend": p.getBackend,
"getBackendServer": p.getBackendServer,
"getPort": p.getPort,
"getWeight": p.getWeight,
"getDomain": p.getDomain,
"getProtocol": p.getProtocol,
"getPassHostHeader": p.getPassHostHeader,
"getPriority": p.getPriority,
"getEntryPoints": p.getEntryPoints,
"getFrontendRule": p.getFrontendRule,
"getFrontendBackend": p.getFrontendBackend,
"hasCircuitBreakerLabels": p.hasCircuitBreakerLabels,
"hasLoadBalancerLabels": p.hasLoadBalancerLabels,
"hasMaxConnLabels": p.hasMaxConnLabels,
"getMaxConnExtractorFunc": p.getMaxConnExtractorFunc,
"getMaxConnAmount": p.getMaxConnAmount,
"getLoadBalancerMethod": p.getLoadBalancerMethod,
"getCircuitBreakerExpression": p.getCircuitBreakerExpression,
"getSticky": p.getSticky,
}
applications, err := p.marathonClient.Applications(nil)
if err != nil {
log.Errorf("Failed to create a client for marathon, error: %s", err)
return nil
}
tasks, err := p.marathonClient.AllTasks(&marathon.AllTasksOpts{Status: "running"})
if err != nil {
log.Errorf("Failed to create a client for marathon, error: %s", err)
return nil
}
//filter tasks
filteredTasks := fun.Filter(func(task marathon.Task) bool {
return p.taskFilter(task, applications, p.ExposedByDefault)
}, tasks.Tasks).([]marathon.Task)
//filter apps
filteredApps := fun.Filter(func(app marathon.Application) bool {
return p.applicationFilter(app, filteredTasks)
}, applications.Apps).([]marathon.Application)
templateObjects := struct {
Applications []marathon.Application
Tasks []marathon.Task
Domain string
}{
filteredApps,
filteredTasks,
p.Domain,
}
configuration, err := p.GetConfiguration("templates/marathon.tmpl", MarathonFuncMap, templateObjects)
if err != nil {
log.Error(err)
}
return configuration
}
func (p *Provider) taskFilter(task marathon.Task, applications *marathon.Applications, exposedByDefaultFlag bool) bool {
application, err := getApplication(task, applications.Apps)
if err != nil {
log.Errorf("Unable to get Marathon application %s for task %s", task.AppID, task.ID)
return false
}
if _, err = processPorts(application, task); err != nil {
log.Errorf("Filtering Marathon task %s from application %s without port: %s", task.ID, application.ID, err)
return false
}
// Filter illegal port label specification.
_, hasPortIndexLabel := p.getLabel(application, labelPortIndex)
_, hasPortLabel := p.getLabel(application, labelPort)
if hasPortIndexLabel && hasPortLabel {
log.Debugf("Filtering Marathon task %s from application %s specifying both traefik.portIndex and traefik.port labels", task.ID, application.ID)
return false
}
// Filter by constraints.
label, _ := p.getLabel(application, "traefik.tags")
constraintTags := strings.Split(label, ",")
if p.MarathonLBCompatibility {
if label, ok := p.getLabel(application, "HAPROXY_GROUP"); ok {
constraintTags = append(constraintTags, label)
}
}
if ok, failingConstraint := p.MatchConstraints(constraintTags); !ok {
if failingConstraint != nil {
log.Debugf("Filtering Marathon task %s from application %s pruned by '%v' constraint", task.ID, application.ID, failingConstraint.String())
}
return false
}
// Filter disabled application.
if !isApplicationEnabled(application, exposedByDefaultFlag) {
log.Debugf("Filtering disabled Marathon task %s from application %s", task.ID, application.ID)
return false
}
// Filter task with existing, bad health check results.
if application.HasHealthChecks() {
if task.HasHealthCheckResults() {
for _, healthcheck := range task.HealthCheckResults {
if !healthcheck.Alive {
log.Debugf("Filtering Marathon task %s from application %s with bad health check", task.ID, application.ID)
return false
}
}
}
}
return true
}
func (p *Provider) applicationFilter(app marathon.Application, filteredTasks []marathon.Task) bool {
label, _ := p.getLabel(app, "traefik.tags")
constraintTags := strings.Split(label, ",")
if p.MarathonLBCompatibility {
if label, ok := p.getLabel(app, "HAPROXY_GROUP"); ok {
constraintTags = append(constraintTags, label)
}
}
if ok, failingConstraint := p.MatchConstraints(constraintTags); !ok {
if failingConstraint != nil {
log.Debugf("Application %v pruned by '%v' constraint", app.ID, failingConstraint.String())
}
return false
}
return fun.Exists(func(task marathon.Task) bool {
return task.AppID == app.ID
}, filteredTasks)
}
func getApplication(task marathon.Task, apps []marathon.Application) (marathon.Application, error) {
for _, application := range apps {
if application.ID == task.AppID {
return application, nil
}
}
return marathon.Application{}, errors.New("Application not found: " + task.AppID)
}
func isApplicationEnabled(application marathon.Application, exposedByDefault bool) bool {
return exposedByDefault && (*application.Labels)["traefik.enable"] != "false" || (*application.Labels)["traefik.enable"] == "true"
}
func (p *Provider) getLabel(application marathon.Application, label string) (string, bool) {
for key, value := range *application.Labels {
if key == label {
return value, true
}
}
return "", false
}
func (p *Provider) getPort(task marathon.Task, applications []marathon.Application) string {
application, err := getApplication(task, applications)
if err != nil {
log.Errorf("Unable to get Marathon application %s for task %s", application.ID, task.ID)
return ""
}
port, err := processPorts(application, task)
if err != nil {
log.Errorf("Unable to process ports for Marathon application %s and task %s: %s", application.ID, task.ID, err)
return ""
}
return strconv.Itoa(port)
}
func (p *Provider) getWeight(task marathon.Task, applications []marathon.Application) string {
application, errApp := getApplication(task, applications)
if errApp != nil {
log.Errorf("Unable to get marathon application from task %s", task.AppID)
return "0"
}
if label, ok := p.getLabel(application, "traefik.weight"); ok {
return label
}
return "0"
}
func (p *Provider) getDomain(application marathon.Application) string {
if label, ok := p.getLabel(application, "traefik.domain"); ok {
return label
}
return p.Domain
}
func (p *Provider) getProtocol(task marathon.Task, applications []marathon.Application) string {
application, errApp := getApplication(task, applications)
if errApp != nil {
log.Errorf("Unable to get marathon application from task %s", task.AppID)
return "http"
}
if label, ok := p.getLabel(application, "traefik.protocol"); ok {
return label
}
return "http"
}
func (p *Provider) getSticky(application marathon.Application) string {
if sticky, ok := p.getLabel(application, "traefik.backend.loadbalancer.sticky"); ok {
return sticky
}
return "false"
}
func (p *Provider) getPassHostHeader(application marathon.Application) string {
if passHostHeader, ok := p.getLabel(application, "traefik.frontend.passHostHeader"); ok {
return passHostHeader
}
return "true"
}
func (p *Provider) getPriority(application marathon.Application) string {
if priority, ok := p.getLabel(application, "traefik.frontend.priority"); ok {
return priority
}
return "0"
}
func (p *Provider) getEntryPoints(application marathon.Application) []string {
if entryPoints, ok := p.getLabel(application, "traefik.frontend.entryPoints"); ok {
return strings.Split(entryPoints, ",")
}
return []string{}
}
// getFrontendRule returns the frontend rule for the specified application, using
// it's label. It returns a default one (Host) if the label is not present.
func (p *Provider) getFrontendRule(application marathon.Application) string {
if label, ok := p.getLabel(application, "traefik.frontend.rule"); ok {
return label
}
if p.MarathonLBCompatibility {
if label, ok := p.getLabel(application, "HAPROXY_0_VHOST"); ok {
return "Host:" + label
}
}
return "Host:" + p.getSubDomain(application.ID) + "." + p.Domain
}
func (p *Provider) getBackend(task marathon.Task, applications []marathon.Application) string {
application, errApp := getApplication(task, applications)
if errApp != nil {
log.Errorf("Unable to get marathon application from task %s", task.AppID)
return ""
}
return p.getFrontendBackend(application)
}
func (p *Provider) getFrontendBackend(application marathon.Application) string {
if label, ok := p.getLabel(application, "traefik.backend"); ok {
return label
}
return provider.Replace("/", "-", application.ID)
}
func (p *Provider) getSubDomain(name string) string {
if p.GroupsAsSubDomains {
splitedName := strings.Split(strings.TrimPrefix(name, "/"), "/")
provider.ReverseStringSlice(&splitedName)
reverseName := strings.Join(splitedName, ".")
return reverseName
}
return strings.Replace(strings.TrimPrefix(name, "/"), "/", "-", -1)
}
func (p *Provider) hasCircuitBreakerLabels(application marathon.Application) bool {
_, ok := p.getLabel(application, "traefik.backend.circuitbreaker.expression")
return ok
}
func (p *Provider) hasLoadBalancerLabels(application marathon.Application) bool {
_, errMethod := p.getLabel(application, "traefik.backend.loadbalancer.method")
_, errSticky := p.getLabel(application, "traefik.backend.loadbalancer.sticky")
return errMethod || errSticky
}
func (p *Provider) hasMaxConnLabels(application marathon.Application) bool {
if _, ok := p.getLabel(application, "traefik.backend.maxconn.amount"); !ok {
return false
}
_, ok := p.getLabel(application, "traefik.backend.maxconn.extractorfunc")
return ok
}
func (p *Provider) getMaxConnAmount(application marathon.Application) int64 {
if label, ok := p.getLabel(application, "traefik.backend.maxconn.amount"); ok {
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 (p *Provider) getMaxConnExtractorFunc(application marathon.Application) string {
if label, ok := p.getLabel(application, "traefik.backend.maxconn.extractorfunc"); ok {
return label
}
return "request.host"
}
func (p *Provider) getLoadBalancerMethod(application marathon.Application) string {
if label, ok := p.getLabel(application, "traefik.backend.loadbalancer.method"); ok {
return label
}
return "wrr"
}
func (p *Provider) getCircuitBreakerExpression(application marathon.Application) string {
if label, ok := p.getLabel(application, "traefik.backend.circuitbreaker.expression"); ok {
return label
}
return "NetworkErrorRatio() > 1"
}
func processPorts(application marathon.Application, task marathon.Task) (int, error) {
if portLabel, ok := (*application.Labels)[labelPort]; ok {
port, err := strconv.Atoi(portLabel)
switch {
case err != nil:
return 0, fmt.Errorf("failed to parse port label: %s", err)
case port <= 0:
return 0, fmt.Errorf("explicitly specified port %d must be larger than zero", port)
}
return port, nil
}
ports := retrieveAvailablePorts(application, task)
if len(ports) == 0 {
return 0, errors.New("no port found")
}
portIndex := 0
portIndexLabel, ok := (*application.Labels)[labelPortIndex]
if ok {
var err error
portIndex, err = strconv.Atoi(portIndexLabel)
switch {
case err != nil:
return 0, fmt.Errorf("failed to parse port index label: %s", err)
case portIndex < 0, portIndex > len(ports)-1:
return 0, fmt.Errorf("port index %d must be within port range (0, %d)", portIndex, len(ports)-1)
}
}
return ports[portIndex], nil
}
func retrieveAvailablePorts(application marathon.Application, task marathon.Task) []int {
// Using default port configuration
if task.Ports != nil && len(task.Ports) > 0 {
return task.Ports
}
// Using port definition if available
if application.PortDefinitions != nil && len(*application.PortDefinitions) > 0 {
var ports []int
for _, def := range *application.PortDefinitions {
if def.Port != nil {
ports = append(ports, *def.Port)
}
}
return ports
}
// If using IP-per-task using this port definition
if application.IPAddressPerTask != nil && len(*((*application.IPAddressPerTask).Discovery).Ports) > 0 {
var ports []int
for _, def := range *((*application.IPAddressPerTask).Discovery).Ports {
ports = append(ports, def.Number)
}
return ports
}
return []int{}
}
func (p *Provider) getBackendServer(task marathon.Task, applications []marathon.Application) string {
application, err := getApplication(task, applications)
if err != nil {
log.Errorf("Unable to get marathon application from task %s", task.AppID)
return ""
}
if len(task.IPAddresses) == 0 {
return ""
} else if len(task.IPAddresses) == 1 {
return task.IPAddresses[0].IPAddress
} else {
ipAddressIdxStr, ok := p.getLabel(application, "traefik.ipAddressIdx")
if !ok {
log.Errorf("Unable to get marathon IPAddress from task %s", task.AppID)
return ""
}
ipAddressIdx, err := strconv.Atoi(ipAddressIdxStr)
if err != nil {
log.Errorf("Invalid marathon IPAddress from task %s", task.AppID)
return ""
}
return task.IPAddresses[ipAddressIdx].IPAddress
}
}