traefik/pkg/server/router/router.go
Ludovic Fernandez 424e2a9439 Add internal provider
Co-authored-by: Julien Salleyron <julien.salleyron@gmail.com>
2019-11-14 16:40:05 +01:00

205 lines
6.1 KiB
Go

package router
import (
"context"
"errors"
"net/http"
"github.com/containous/alice"
"github.com/containous/traefik/v2/pkg/config/runtime"
"github.com/containous/traefik/v2/pkg/log"
"github.com/containous/traefik/v2/pkg/middlewares/accesslog"
"github.com/containous/traefik/v2/pkg/middlewares/recovery"
"github.com/containous/traefik/v2/pkg/middlewares/tracing"
"github.com/containous/traefik/v2/pkg/rules"
"github.com/containous/traefik/v2/pkg/server/internal"
"github.com/containous/traefik/v2/pkg/server/middleware"
)
const (
recoveryMiddlewareName = "traefik-internal-recovery"
)
type middlewareBuilder interface {
BuildChain(ctx context.Context, names []string) *alice.Chain
}
type responseModifierBuilder interface {
Build(ctx context.Context, names []string) func(*http.Response) error
}
type serviceManager interface {
BuildHTTP(rootCtx context.Context, serviceName string, responseModifier func(*http.Response) error) (http.Handler, error)
LaunchHealthCheck()
}
// Manager A route/router manager
type Manager struct {
routerHandlers map[string]http.Handler
serviceManager serviceManager
middlewaresBuilder middlewareBuilder
chainBuilder *middleware.ChainBuilder
modifierBuilder responseModifierBuilder
conf *runtime.Configuration
}
// NewManager Creates a new Manager
func NewManager(conf *runtime.Configuration,
serviceManager serviceManager,
middlewaresBuilder middlewareBuilder,
modifierBuilder responseModifierBuilder,
chainBuilder *middleware.ChainBuilder,
) *Manager {
return &Manager{
routerHandlers: make(map[string]http.Handler),
serviceManager: serviceManager,
middlewaresBuilder: middlewaresBuilder,
modifierBuilder: modifierBuilder,
chainBuilder: chainBuilder,
conf: conf,
}
}
func (m *Manager) getHTTPRouters(ctx context.Context, entryPoints []string, tls bool) map[string]map[string]*runtime.RouterInfo {
if m.conf != nil {
return m.conf.GetRoutersByEntryPoints(ctx, entryPoints, tls)
}
return make(map[string]map[string]*runtime.RouterInfo)
}
// BuildHandlers Builds handler for all entry points
func (m *Manager) BuildHandlers(rootCtx context.Context, entryPoints []string, tls bool) map[string]http.Handler {
entryPointHandlers := make(map[string]http.Handler)
for entryPointName, routers := range m.getHTTPRouters(rootCtx, entryPoints, tls) {
entryPointName := entryPointName
ctx := log.With(rootCtx, log.Str(log.EntryPointName, entryPointName))
handler, err := m.buildEntryPointHandler(ctx, routers)
if err != nil {
log.FromContext(ctx).Error(err)
continue
}
handlerWithAccessLog, err := alice.New(func(next http.Handler) (http.Handler, error) {
return accesslog.NewFieldHandler(next, log.EntryPointName, entryPointName, accesslog.AddOriginFields), nil
}).Then(handler)
if err != nil {
log.FromContext(ctx).Error(err)
entryPointHandlers[entryPointName] = handler
} else {
entryPointHandlers[entryPointName] = handlerWithAccessLog
}
}
for _, entryPointName := range entryPoints {
ctx := log.With(rootCtx, log.Str(log.EntryPointName, entryPointName))
handler, ok := entryPointHandlers[entryPointName]
if !ok || handler == nil {
handler = BuildDefaultHTTPRouter()
}
handlerWithMiddlewares, err := m.chainBuilder.Build(ctx, entryPointName).Then(handler)
if err != nil {
log.FromContext(ctx).Error(err)
continue
}
entryPointHandlers[entryPointName] = handlerWithMiddlewares
}
m.serviceManager.LaunchHealthCheck()
return entryPointHandlers
}
func (m *Manager) buildEntryPointHandler(ctx context.Context, configs map[string]*runtime.RouterInfo) (http.Handler, error) {
router, err := rules.NewRouter()
if err != nil {
return nil, err
}
for routerName, routerConfig := range configs {
ctxRouter := log.With(internal.AddProviderInContext(ctx, routerName), log.Str(log.RouterName, routerName))
logger := log.FromContext(ctxRouter)
handler, err := m.buildRouterHandler(ctxRouter, routerName, routerConfig)
if err != nil {
routerConfig.AddError(err, true)
logger.Error(err)
continue
}
err = router.AddRoute(routerConfig.Rule, routerConfig.Priority, handler)
if err != nil {
routerConfig.AddError(err, true)
logger.Error(err)
continue
}
}
router.SortRoutes()
chain := alice.New()
chain = chain.Append(func(next http.Handler) (http.Handler, error) {
return recovery.New(ctx, next, recoveryMiddlewareName)
})
return chain.Then(router)
}
func (m *Manager) buildRouterHandler(ctx context.Context, routerName string, routerConfig *runtime.RouterInfo) (http.Handler, error) {
if handler, ok := m.routerHandlers[routerName]; ok {
return handler, nil
}
handler, err := m.buildHTTPHandler(ctx, routerConfig, routerName)
if err != nil {
return nil, err
}
handlerWithAccessLog, err := alice.New(func(next http.Handler) (http.Handler, error) {
return accesslog.NewFieldHandler(next, accesslog.RouterName, routerName, nil), nil
}).Then(handler)
if err != nil {
log.FromContext(ctx).Error(err)
m.routerHandlers[routerName] = handler
} else {
m.routerHandlers[routerName] = handlerWithAccessLog
}
return m.routerHandlers[routerName], nil
}
func (m *Manager) buildHTTPHandler(ctx context.Context, router *runtime.RouterInfo, routerName string) (http.Handler, error) {
var qualifiedNames []string
for _, name := range router.Middlewares {
qualifiedNames = append(qualifiedNames, internal.GetQualifiedName(ctx, name))
}
router.Middlewares = qualifiedNames
rm := m.modifierBuilder.Build(ctx, qualifiedNames)
if router.Service == "" {
return nil, errors.New("the service is missing on the router")
}
sHandler, err := m.serviceManager.BuildHTTP(ctx, router.Service, rm)
if err != nil {
return nil, err
}
mHandler := m.middlewaresBuilder.BuildChain(ctx, router.Middlewares)
tHandler := func(next http.Handler) (http.Handler, error) {
return tracing.NewForwarder(ctx, routerName, router.Service, next), nil
}
return alice.New().Extend(*mHandler).Append(tHandler).Then(sHandler)
}
// BuildDefaultHTTPRouter creates a default HTTP router.
func BuildDefaultHTTPRouter() http.Handler {
return http.NotFoundHandler()
}