Refactor traefik with package

Split a bit traefik into package. The idea behind this refactor is to
start move inter-dependencies away and do some DRY or SRP.

- Adds a `provider` package, with providers except `web.go`
- Adds a `types` package with common struct.
- Move `gen.go` to an `autogen` package

Signed-off-by: Vincent Demeester <vincent@sbr.pm>

configuration.go

@@ -1,9 +1,10 @@
 package main
 
 import (
-	"errors"
-	"strings"
 	"time"
+
+	"github.com/emilevauge/traefik/provider"
+	"github.com/emilevauge/traefik/types"
 )
 
 type GlobalConfiguration struct {
@@ -14,14 +15,14 @@ type GlobalConfiguration struct {
 	CertFile, KeyFile         string
 	LogLevel                  string
 	ProvidersThrottleDuration time.Duration
-	Docker                    *DockerProvider
-	File                      *FileProvider
+	Docker                    *provider.DockerProvider
+	File                      *provider.FileProvider
 	Web                       *WebProvider
-	Marathon                  *MarathonProvider
-	Consul                    *ConsulProvider
-	Etcd                      *EtcdProvider
-	Zookeeper                 *ZookepperProvider
-	Boltdb                    *BoltDbProvider
+	Marathon                  *provider.MarathonProvider
+	Consul                    *provider.ConsulProvider
+	Etcd                      *provider.EtcdProvider
+	Zookeeper                 *provider.ZookepperProvider
+	Boltdb                    *provider.BoltDbProvider
 }
 
 func NewGlobalConfiguration() *GlobalConfiguration {
@@ -35,79 +36,4 @@ func NewGlobalConfiguration() *GlobalConfiguration {
 	return globalConfiguration
 }
 
-// Backend configuration
-type Backend struct {
-	Servers        map[string]Server `json:"servers,omitempty"`
-	CircuitBreaker *CircuitBreaker   `json:"circuitBreaker,omitempty"`
-	LoadBalancer   *LoadBalancer     `json:"loadBalancer,omitempty"`
-}
-
-// LoadBalancer configuration
-type LoadBalancer struct {
-	Method string `json:"method,omitempty"`
-}
-
-// CircuitBreaker configuration
-type CircuitBreaker struct {
-	Expression string `json:"expression,omitempty"`
-}
-
-// Server configuration
-type Server struct {
-	URL    string `json:"url,omitempty"`
-	Weight int    `json:"weight,omitempty"`
-}
-
-// Route configuration
-type Route struct {
-	Rule  string `json:"rule,omitempty"`
-	Value string `json:"value,omitempty"`
-}
-
-// Frontend configuration
-type Frontend struct {
-	PassHostHeader bool             `json:"passHostHeader,omitempty"`
-	Backend        string           `json:"backend,omitempty"`
-	Routes         map[string]Route `json:"routes,omitempty"`
-}
-
-// Configuration of a provider
-type Configuration struct {
-	Backends  map[string]*Backend  `json:"backends,omitempty"`
-	Frontends map[string]*Frontend `json:"frontends,omitempty"`
-}
-
-// Load Balancer Method
-type LoadBalancerMethod uint8
-
-const (
-	// wrr (default) = Weighted Round Robin
-	wrr LoadBalancerMethod = iota
-	// drr = Dynamic Round Robin
-	drr
-)
-
-var loadBalancerMethodNames = []string{
-	"wrr",
-	"drr",
-}
-
-func NewLoadBalancerMethod(loadBalancer *LoadBalancer) (LoadBalancerMethod, error) {
-	if loadBalancer != nil {
-		for i, name := range loadBalancerMethodNames {
-			if strings.EqualFold(name, loadBalancer.Method) {
-				return LoadBalancerMethod(i), nil
-			}
-		}
-	}
-	return wrr, ErrInvalidLoadBalancerMethod
-}
-
-var ErrInvalidLoadBalancerMethod = errors.New("Invalid method, using default")
-
-type configMessage struct {
-	providerName  string
-	configuration *Configuration
-}
-
-type configs map[string]*Configuration
+type configs map[string]*types.Configuration