traefik/traefik.go
Thorhallur Sverrisson f534d8817f Adding caching and merging of configurations
Configurations are now cached from each provider separately so that
we can merge them together when one provider has changed config.

The Web module also returns full config info through the HTML call,
but REST API is working on a separate web configuration that is
sent in just like any other.
2015-09-23 11:25:11 +00:00

313 lines
9.8 KiB
Go

package main
import (
fmtlog "log"
"net"
"net/http"
"net/url"
"os"
"os/signal"
"reflect"
"strings"
"syscall"
"time"
"github.com/BurntSushi/toml"
log "github.com/Sirupsen/logrus"
"github.com/codegangsta/negroni"
"github.com/emilevauge/traefik/middlewares"
"github.com/gorilla/mux"
"github.com/mailgun/manners"
"github.com/mailgun/oxy/cbreaker"
"github.com/mailgun/oxy/forward"
"github.com/mailgun/oxy/roundrobin"
"github.com/thoas/stats"
"github.com/unrolled/render"
"gopkg.in/alecthomas/kingpin.v2"
"runtime"
)
var (
globalConfigFile = kingpin.Arg("conf", "Main configration file.").Default("traefik.toml").String()
currentConfigurations = make(configs)
metrics = stats.New()
oxyLogger = &OxyLogger{}
templatesRenderer = render.New(render.Options{
Directory: "templates",
Asset: Asset,
AssetNames: AssetNames,
})
)
type configMessage struct {
providerName string
configuration *Configuration
}
type configs map[string]*Configuration
func main() {
runtime.GOMAXPROCS(runtime.NumCPU())
kingpin.Parse()
fmtlog.SetFlags(fmtlog.Lshortfile | fmtlog.LstdFlags)
var srv *manners.GracefulServer
var configurationRouter *mux.Router
var configurationChan = make(chan configMessage, 10)
defer close(configurationChan)
var sigs = make(chan os.Signal, 1)
defer close(sigs)
var stopChan = make(chan bool)
defer close(stopChan)
var providers = []Provider{}
signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
// load global configuration
globalConfiguration := LoadFileConfig(*globalConfigFile)
loggerMiddleware := middlewares.NewLogger(globalConfiguration.AccessLogsFile)
defer loggerMiddleware.Close()
// logging
level, err := log.ParseLevel(strings.ToLower(globalConfiguration.LogLevel))
if err != nil {
log.Fatal("Error getting level", err)
}
log.SetLevel(level)
if len(globalConfiguration.TraefikLogsFile) > 0 {
fi, err := os.OpenFile(globalConfiguration.TraefikLogsFile, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
defer fi.Close()
if err != nil {
log.Fatal("Error opening file", err)
} else {
log.SetOutput(fi)
log.SetFormatter(&log.TextFormatter{DisableColors: true, FullTimestamp: true, DisableSorting: true})
}
} else {
log.SetFormatter(&log.TextFormatter{FullTimestamp: true, DisableSorting: true})
}
configurationRouter = LoadDefaultConfig(globalConfiguration)
// listen new configurations from providers
go func() {
for {
configMsg := <-configurationChan
log.Infof("Configuration receveived from provider %v: %+v", configMsg.providerName, configMsg.configuration)
if configMsg.configuration == nil {
log.Info("Skipping empty configuration")
} else if reflect.DeepEqual(currentConfigurations[configMsg.providerName], configMsg.configuration) {
log.Info("Skipping same configuration")
} else {
// Copy configurations to new map so we don't change current if LoadConfig fails
newConfigurations := make(configs)
for k, v := range currentConfigurations {
newConfigurations[k] = v
}
newConfigurations[configMsg.providerName] = configMsg.configuration
newConfigurationRouter, err := LoadConfig(newConfigurations, globalConfiguration)
if err == nil {
currentConfigurations = newConfigurations
configurationRouter = newConfigurationRouter
oldServer := srv
newsrv := prepareServer(configurationRouter, globalConfiguration, oldServer, loggerMiddleware, metrics)
go startServer(newsrv, globalConfiguration)
srv = newsrv
time.Sleep(2 * time.Second)
if oldServer != nil {
log.Info("Stopping old server")
oldServer.Close()
}
} else {
log.Error("Error loading new configuration, aborted ", err)
}
}
}
}()
// configure providers
if globalConfiguration.Docker != nil {
providers = append(providers, globalConfiguration.Docker)
}
if globalConfiguration.Marathon != nil {
providers = append(providers, globalConfiguration.Marathon)
}
if globalConfiguration.File != nil {
if len(globalConfiguration.File.Filename) == 0 {
// no filename, setting to global config file
globalConfiguration.File.Filename = *globalConfigFile
}
providers = append(providers, globalConfiguration.File)
}
if globalConfiguration.Web != nil {
providers = append(providers, globalConfiguration.Web)
}
if globalConfiguration.Consul != nil {
providers = append(providers, globalConfiguration.Consul)
}
// start providers
for _, provider := range providers {
log.Infof("Starting provider %v %+v", reflect.TypeOf(provider), provider)
currentProvider := provider
go func() {
currentProvider.Provide(configurationChan)
}()
}
go func() {
sig := <-sigs
log.Infof("I have to go... %+v", sig)
log.Info("Stopping server")
srv.Close()
stopChan <- true
}()
//negroni.Use(middlewares.NewCircuitBreaker(oxyLogger))
//negroni.Use(middlewares.NewRoutes(configurationRouter))
srv = prepareServer(configurationRouter, globalConfiguration, nil, loggerMiddleware, metrics)
go startServer(srv, globalConfiguration)
<-stopChan
log.Info("Shutting down")
}
func startServer(srv *manners.GracefulServer, globalConfiguration *GlobalConfiguration) {
log.Info("Starting server")
if len(globalConfiguration.CertFile) > 0 && len(globalConfiguration.KeyFile) > 0 {
err := srv.ListenAndServeTLS(globalConfiguration.CertFile, globalConfiguration.KeyFile)
if err != nil {
netOpError, ok := err.(*net.OpError)
if ok && netOpError.Err.Error() != "use of closed network connection" {
log.Fatal("Error creating server: ", err)
}
}
} else {
err := srv.ListenAndServe()
if err != nil {
netOpError, ok := err.(*net.OpError)
if ok && netOpError.Err.Error() != "use of closed network connection" {
log.Fatal("Error creating server: ", err)
}
}
}
log.Info("Server stopped")
}
func prepareServer(router *mux.Router, globalConfiguration *GlobalConfiguration, oldServer *manners.GracefulServer, middlewares ...negroni.Handler) *manners.GracefulServer {
log.Info("Preparing server")
// middlewares
var negroni = negroni.New()
for _, middleware := range middlewares {
negroni.Use(middleware)
}
negroni.UseHandler(router)
if oldServer == nil {
return manners.NewWithServer(
&http.Server{
Addr: globalConfiguration.Port,
Handler: negroni,
})
} else {
server, err := oldServer.HijackListener(&http.Server{
Addr: globalConfiguration.Port,
Handler: negroni,
}, nil)
if err != nil {
log.Fatalf("Error hijacking server %s", err)
return nil
} else {
return server
}
}
}
func LoadConfig(configurations configs, globalConfiguration *GlobalConfiguration) (*mux.Router, error) {
router := mux.NewRouter()
router.NotFoundHandler = http.HandlerFunc(notFoundHandler)
backends := map[string]http.Handler{}
for _, configuration := range configurations {
for frontendName, frontend := range configuration.Frontends {
log.Debugf("Creating frontend %s", frontendName)
fwd, _ := forward.New(forward.Logger(oxyLogger))
newRoute := router.NewRoute().Name(frontendName)
for routeName, route := range frontend.Routes {
log.Debugf("Creating route %s %s:%s", routeName, route.Rule, route.Value)
newRouteReflect := Invoke(newRoute, route.Rule, route.Value)
newRoute = newRouteReflect[0].Interface().(*mux.Route)
}
if backends[frontend.Backend] == nil {
log.Debugf("Creating backend %s", frontend.Backend)
var lb http.Handler
rr, _ := roundrobin.New(fwd)
lbMethod, err := NewLoadBalancerMethod(configuration.Backends[frontend.Backend].LoadBalancer)
if err != nil {
configuration.Backends[frontend.Backend].LoadBalancer = &LoadBalancer{Method: "wrr"}
}
switch lbMethod {
case drr:
log.Debugf("Creating load-balancer drr")
rebalancer, _ := roundrobin.NewRebalancer(rr, roundrobin.RebalancerLogger(oxyLogger))
lb = rebalancer
for serverName, server := range configuration.Backends[frontend.Backend].Servers {
url, err := url.Parse(server.URL)
if err != nil {
return nil, err
}
log.Debugf("Creating server %s %s", serverName, url.String())
rebalancer.UpsertServer(url, roundrobin.Weight(server.Weight))
}
case wrr:
log.Debugf("Creating load-balancer wrr")
lb = rr
for serverName, server := range configuration.Backends[frontend.Backend].Servers {
url, err := url.Parse(server.URL)
if err != nil {
return nil, err
}
log.Debugf("Creating server %s %s", serverName, url.String())
rr.UpsertServer(url, roundrobin.Weight(server.Weight))
}
}
var negroni = negroni.New()
if configuration.Backends[frontend.Backend].CircuitBreaker != nil {
log.Debugf("Creating circuit breaker %s", configuration.Backends[frontend.Backend].CircuitBreaker.Expression)
negroni.Use(middlewares.NewCircuitBreaker(lb, configuration.Backends[frontend.Backend].CircuitBreaker.Expression, cbreaker.Logger(oxyLogger)))
} else {
negroni.UseHandler(lb)
}
backends[frontend.Backend] = negroni
} else {
log.Debugf("Reusing backend %s", frontend.Backend)
}
// stream.New(backends[frontend.Backend], stream.Retry("IsNetworkError() && Attempts() <= " + strconv.Itoa(globalConfiguration.Replay)), stream.Logger(oxyLogger))
newRoute.Handler(backends[frontend.Backend])
err := newRoute.GetError()
if err != nil {
log.Error("Error building route: %s", err)
}
}
}
return router, nil
}
func Invoke(any interface{}, name string, args ...interface{}) []reflect.Value {
inputs := make([]reflect.Value, len(args))
for i := range args {
inputs[i] = reflect.ValueOf(args[i])
}
return reflect.ValueOf(any).MethodByName(name).Call(inputs)
}
func LoadFileConfig(file string) *GlobalConfiguration {
configuration := NewGlobalConfiguration()
if _, err := toml.DecodeFile(file, configuration); err != nil {
log.Fatal("Error reading file ", err)
}
log.Debugf("Global configuration loaded %+v", configuration)
return configuration
}