traefik/provider/marathon/config.go
2018-03-26 15:32:04 +02:00

344 lines
11 KiB
Go

package marathon
import (
"errors"
"fmt"
"math"
"strconv"
"strings"
"text/template"
"github.com/containous/traefik/log"
"github.com/containous/traefik/provider"
"github.com/containous/traefik/provider/label"
"github.com/containous/traefik/types"
"github.com/gambol99/go-marathon"
)
const defaultService = ""
type appData struct {
marathon.Application
SegmentLabels map[string]string
SegmentName string
}
func (p *Provider) buildConfigurationV2(applications *marathon.Applications) *types.Configuration {
var MarathonFuncMap = template.FuncMap{
"getDomain": label.GetFuncString(label.TraefikDomain, p.Domain), // see https://github.com/containous/traefik/pull/1693
"getSubDomain": p.getSubDomain, // see https://github.com/containous/traefik/pull/1693
"getBackendName": p.getBackendName,
// Backend functions
"getPort": getPort,
"getCircuitBreaker": label.GetCircuitBreaker,
"getLoadBalancer": label.GetLoadBalancer,
"getMaxConn": label.GetMaxConn,
"getHealthCheck": label.GetHealthCheck,
"getBuffering": label.GetBuffering,
"getServers": p.getServers,
// Frontend functions
"getSegmentNameSuffix": getSegmentNameSuffix,
"getFrontendRule": p.getFrontendRule,
"getFrontendName": p.getFrontendName,
"getPassHostHeader": label.GetFuncBool(label.TraefikFrontendPassHostHeader, label.DefaultPassHostHeaderBool),
"getPassTLSCert": label.GetFuncBool(label.TraefikFrontendPassTLSCert, label.DefaultPassTLSCert),
"getPriority": label.GetFuncInt(label.TraefikFrontendPriority, label.DefaultFrontendPriorityInt),
"getEntryPoints": label.GetFuncSliceString(label.TraefikFrontendEntryPoints),
"getBasicAuth": label.GetFuncSliceString(label.TraefikFrontendAuthBasic),
"getRedirect": label.GetRedirect,
"getErrorPages": label.GetErrorPages,
"getRateLimit": label.GetRateLimit,
"getHeaders": label.GetHeaders,
"getWhiteList": label.GetWhiteList,
}
var apps []*appData
for _, app := range applications.Apps {
if p.applicationFilter(app) {
// Tasks
var filteredTasks []*marathon.Task
for _, task := range app.Tasks {
if p.taskFilter(*task, app) {
filteredTasks = append(filteredTasks, task)
logIllegalServices(*task, app)
}
}
if len(filteredTasks) == 0 {
log.Warnf("No valid tasks for application %s", app.ID)
continue
}
app.Tasks = filteredTasks
// segments
segmentProperties := label.ExtractTraefikLabels(stringValueMap(app.Labels))
for segmentName, labels := range segmentProperties {
data := &appData{
Application: app,
SegmentLabels: labels,
SegmentName: segmentName,
}
apps = append(apps, data)
}
}
}
templateObjects := struct {
Applications []*appData
Domain string
}{
Applications: apps,
Domain: p.Domain,
}
configuration, err := p.GetConfiguration("templates/marathon.tmpl", MarathonFuncMap, templateObjects)
if err != nil {
log.Errorf("Failed to render Marathon configuration template: %v", err)
}
return configuration
}
func (p *Provider) applicationFilter(app marathon.Application) bool {
// Filter disabled application.
if !label.IsEnabled(stringValueMap(app.Labels), p.ExposedByDefault) {
log.Debugf("Filtering disabled Marathon application %s", app.ID)
return false
}
// Filter by constraints.
constraintTags := label.GetSliceStringValue(stringValueMap(app.Labels), label.TraefikTags)
if p.MarathonLBCompatibility {
if haGroup := label.GetStringValue(stringValueMap(app.Labels), labelLbCompatibilityGroup, ""); len(haGroup) > 0 {
constraintTags = append(constraintTags, haGroup)
}
}
if p.FilterMarathonConstraints && app.Constraints != nil {
for _, constraintParts := range *app.Constraints {
constraintTags = append(constraintTags, strings.Join(constraintParts, ":"))
}
}
if ok, failingConstraint := p.MatchConstraints(constraintTags); !ok {
if failingConstraint != nil {
log.Debugf("Filtering Marathon application %s pruned by %q constraint", app.ID, failingConstraint.String())
}
return false
}
return true
}
func (p *Provider) taskFilter(task marathon.Task, application marathon.Application) bool {
if task.State != string(taskStateRunning) {
return false
}
if ready := p.readyChecker.Do(task, application); !ready {
log.Infof("Filtering unready task %s from application %s", task.ID, application.ID)
return false
}
return true
}
// logIllegalServices logs illegal service configurations.
// While we cannot filter on the service level, they will eventually get
// rejected once the server configuration is rendered.
func logIllegalServices(task marathon.Task, app marathon.Application) {
segmentProperties := label.ExtractTraefikLabels(stringValueMap(app.Labels))
for segmentName, labels := range segmentProperties {
// Check for illegal/missing ports.
if _, err := processPorts(app, task, labels); err != nil {
log.Warnf("%s has an illegal configuration: no proper port available", identifier(app, task, segmentName))
continue
}
// Check for illegal port label combinations.
hasPortLabel := label.Has(labels, label.TraefikPort)
hasPortIndexLabel := label.Has(labels, label.TraefikPortIndex)
if hasPortLabel && hasPortIndexLabel {
log.Warnf("%s has both port and port index specified; port will take precedence", identifier(app, task, segmentName))
}
}
}
func getSegmentNameSuffix(serviceName string) string {
if len(serviceName) > 0 {
return "-service-" + provider.Normalize(serviceName)
}
return ""
}
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) getBackendName(app appData) string {
value := label.GetStringValue(app.SegmentLabels, label.TraefikBackend, "")
if len(value) > 0 {
return provider.Normalize("backend" + value)
}
return provider.Normalize("backend" + app.ID + getSegmentNameSuffix(app.SegmentName))
}
func (p *Provider) getFrontendName(app appData) string {
return provider.Normalize("frontend" + app.ID + getSegmentNameSuffix(app.SegmentName))
}
// getFrontendRule returns the frontend rule for the specified application, using
// its label. If service is provided, it will look for serviceName label before generic one.
// It returns a default one (Host) if the label is not present.
func (p *Provider) getFrontendRule(app appData) string {
if value := label.GetStringValue(app.SegmentLabels, label.TraefikFrontendRule, ""); len(value) > 0 {
return value
}
if p.MarathonLBCompatibility {
if value := label.GetStringValue(stringValueMap(app.Labels), labelLbCompatibility, ""); len(value) > 0 {
return "Host:" + value
}
}
if len(app.SegmentName) > 0 {
return "Host:" + strings.ToLower(provider.Normalize(app.SegmentName)) + "." + p.getSubDomain(app.ID) + "." + p.Domain
}
return "Host:" + p.getSubDomain(app.ID) + "." + p.Domain
}
func getPort(task marathon.Task, app appData) string {
port, err := processPorts(app.Application, task, app.SegmentLabels)
if err != nil {
log.Errorf("Unable to process ports for %s: %s", identifier(app.Application, task, app.SegmentName), err)
return ""
}
return strconv.Itoa(port)
}
// processPorts returns the configured port.
// An explicitly specified port is preferred. If none is specified, it selects
// one of the available port. The first such found port is returned unless an
// optional index is provided.
func processPorts(app marathon.Application, task marathon.Task, labels map[string]string) (int, error) {
if label.Has(labels, label.TraefikPort) {
port := label.GetIntValue(labels, label.TraefikPort, 0)
if port <= 0 {
return 0, fmt.Errorf("explicitly specified port %d must be larger than zero", port)
} else if port > 0 {
return port, nil
}
}
ports := retrieveAvailablePorts(app, task)
if len(ports) == 0 {
return 0, errors.New("no port found")
}
portIndex := label.GetIntValue(labels, label.TraefikPortIndex, 0)
if portIndex < 0 || portIndex > len(ports)-1 {
return 0, fmt.Errorf("index %d must be within range (0, %d)", portIndex, len(ports)-1)
}
return ports[portIndex], nil
}
func retrieveAvailablePorts(app marathon.Application, task marathon.Task) []int {
// Using default port configuration
if len(task.Ports) > 0 {
return task.Ports
}
// Using port definition if available
if app.PortDefinitions != nil && len(*app.PortDefinitions) > 0 {
var ports []int
for _, def := range *app.PortDefinitions {
if def.Port != nil {
ports = append(ports, *def.Port)
}
}
return ports
}
// If using IP-per-task using this port definition
if app.IPAddressPerTask != nil && app.IPAddressPerTask.Discovery != nil && len(*(app.IPAddressPerTask.Discovery.Ports)) > 0 {
var ports []int
for _, def := range *(app.IPAddressPerTask.Discovery.Ports) {
ports = append(ports, def.Number)
}
return ports
}
return []int{}
}
func identifier(app marathon.Application, task marathon.Task, segmentName string) string {
id := fmt.Sprintf("Marathon task %s from application %s", task.ID, app.ID)
if segmentName != "" {
id += fmt.Sprintf(" (segment: %s)", segmentName)
}
return id
}
func (p *Provider) getServers(app appData) map[string]types.Server {
var servers map[string]types.Server
for _, task := range app.Tasks {
host := p.getBackendServer(*task, app)
if len(host) == 0 {
continue
}
if servers == nil {
servers = make(map[string]types.Server)
}
port := getPort(*task, app)
protocol := label.GetStringValue(app.SegmentLabels, label.TraefikProtocol, label.DefaultProtocol)
serverName := provider.Normalize("server-" + task.ID + getSegmentNameSuffix(app.SegmentName))
servers[serverName] = types.Server{
URL: fmt.Sprintf("%s://%s:%v", protocol, host, port),
Weight: label.GetIntValue(app.SegmentLabels, label.TraefikWeight, label.DefaultWeightInt),
}
}
return servers
}
func (p *Provider) getBackendServer(task marathon.Task, app appData) string {
if app.IPAddressPerTask == nil || p.ForceTaskHostname {
return task.Host
}
numTaskIPAddresses := len(task.IPAddresses)
switch numTaskIPAddresses {
case 0:
log.Errorf("Missing IP address for Marathon application %s on task %s", app.ID, task.ID)
return ""
case 1:
return task.IPAddresses[0].IPAddress
default:
ipAddressIdx := label.GetIntValue(stringValueMap(app.Labels), labelIPAddressIdx, math.MinInt32)
if ipAddressIdx == math.MinInt32 {
log.Errorf("Found %d task IP addresses but missing IP address index for Marathon application %s on task %s",
numTaskIPAddresses, app.ID, task.ID)
return ""
}
if ipAddressIdx < 0 || ipAddressIdx > numTaskIPAddresses {
log.Errorf("Cannot use IP address index to select from %d task IP addresses for Marathon application %s on task %s",
numTaskIPAddresses, app.ID, task.ID)
return ""
}
return task.IPAddresses[ipAddressIdx].IPAddress
}
}