router.go

package server

// Code auto-generated. Do not edit.

import (
	"compress/gzip"
	"context"
	"log"
	"net/http"
	_ "net/http/pprof"
	"os"
	"os/signal"
	"path"
	"syscall"
	"time"

	"github.com/Clever/go-process-metrics/metrics"
	"github.com/Clever/wag/samples/v8/gen-go/tracing"
	"github.com/gorilla/handlers"
	"github.com/gorilla/mux"
	"github.com/kardianos/osext"
	"gopkg.in/Clever/kayvee-go.v6/logger"
	kvMiddleware "gopkg.in/Clever/kayvee-go.v6/middleware"
)

// Server defines a HTTP server that implements the Controller interface.
type Server struct {
	// Handler should generally not be changed. It exposed to make testing easier.
	Handler http.Handler
	addr    string
	l       logger.KayveeLogger
	config  serverConfig
}

type serverConfig struct {
	compressionLevel int
}

func CompressionLevel(level int) func(*serverConfig) {
	return func(c *serverConfig) {
		c.compressionLevel = level
	}
}

// Serve starts the server. It will return if an error occurs.
func (s *Server) Serve() error {
	isLocal := os.Getenv("_IS_LOCAL") == "true"
	if !isLocal {
		go startLoggingProcessMetrics()
	}

	go func() {
		// This should never return. Listen on the pprof port
		log.Printf("PProf server crashed: %s", http.ListenAndServe("localhost:6060", nil))
	}()

	dir, err := osext.ExecutableFolder()
	if err != nil {
		log.Fatal(err)
	}
	if err := logger.SetGlobalRouting(path.Join(dir, "kvconfig.yml")); err != nil {
		s.l.Info("please provide a kvconfig.yml file to enable app log routing")
	}

	s.l.Counter("server-started")

	// Give the sever 30 seconds to shut down
	server := &http.Server{
		Addr:        s.addr,
		Handler:     s.Handler,
		IdleTimeout: 3 * time.Minute,
	}
	server.SetKeepAlivesEnabled(true)

	// Give the server 30 seconds to shut down gracefully after it receives a signal
	shutdown := make(chan struct{})
	go func() {
		c := make(chan os.Signal, 1)
		signal.Notify(c, os.Interrupt, os.Signal(syscall.SIGTERM))
		sig := <-c
		s.l.InfoD("shutdown-initiated", logger.M{"signal": sig.String()})
		ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
		defer cancel()
		defer close(shutdown)
		if err := server.Shutdown(ctx); err != nil {
			s.l.CriticalD("error-during-shutdown", logger.M{"error": err.Error()})
		}
	}()

	if err := server.ListenAndServe(); err != http.ErrServerClosed {
		return err
	}
	// ensure we wait for graceful shutdown
	<-shutdown

	return nil
}

type handler struct {
	Controller
}

func startLoggingProcessMetrics() {
	metrics.Log("swagger-test", 1*time.Minute)
}

func withMiddleware(serviceName string, router http.Handler, m []func(http.Handler) http.Handler, config serverConfig) http.Handler {
	handler := router

	// compress everything
	handler = handlers.CompressHandlerLevel(handler, config.compressionLevel)

	// Wrap the middleware in the opposite order specified so that when called then run
	// in the order specified
	for i := len(m) - 1; i >= 0; i-- {
		handler = m[i](handler)
	}
	handler = PanicMiddleware(handler)
	// Logging middleware comes last, i.e. will be run first.
	// This makes it so that other middleware has access to the logger
	// that kvMiddleware injects into the request context.
	handler = kvMiddleware.New(handler, serviceName)
	return handler
}

// New returns a Server that implements the Controller interface. It will start when "Serve" is called.
func New(c Controller, addr string, options ...func(*serverConfig)) *Server {
	return NewWithMiddleware(c, addr, []func(http.Handler) http.Handler{}, options...)
}

// NewRouter returns a mux.Router with no middleware. This is so we can attach additional routes to the
// router if necessary
func NewRouter(c Controller) *mux.Router {
	return newRouter(c)
}

func newRouter(c Controller) *mux.Router {
	router := mux.NewRouter()
	router.Use(tracing.MuxServerMiddleware("swagger-test"))
	h := handler{Controller: c}

	router.Methods("GET").Path("/v1/authors").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		logger.FromContext(r.Context()).AddContext("op", "getAuthors")
		h.GetAuthorsHandler(r.Context(), w, r)
	})

	router.Methods("PUT").Path("/v1/authors").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		logger.FromContext(r.Context()).AddContext("op", "getAuthorsWithPut")
		h.GetAuthorsWithPutHandler(r.Context(), w, r)
	})

	router.Methods("GET").Path("/v1/books").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		logger.FromContext(r.Context()).AddContext("op", "getBooks")
		h.GetBooksHandler(r.Context(), w, r)
	})

	router.Methods("POST").Path("/v1/books").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		logger.FromContext(r.Context()).AddContext("op", "createBook")
		h.CreateBookHandler(r.Context(), w, r)
	})

	router.Methods("PUT").Path("/v1/books").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		logger.FromContext(r.Context()).AddContext("op", "putBook")
		h.PutBookHandler(r.Context(), w, r)
	})

	router.Methods("GET").Path("/v1/books/{book_id}").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		logger.FromContext(r.Context()).AddContext("op", "getBookByID")
		h.GetBookByIDHandler(r.Context(), w, r)
	})

	router.Methods("GET").Path("/v1/books2/{id}").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		logger.FromContext(r.Context()).AddContext("op", "getBookByID2")
		h.GetBookByID2Handler(r.Context(), w, r)
	})

	router.Methods("GET").Path("/v1/health/check").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		logger.FromContext(r.Context()).AddContext("op", "healthCheck")
		h.HealthCheckHandler(r.Context(), w, r)
	})

	return router
}

// NewWithMiddleware returns a Server that implemenets the Controller interface. It runs the
// middleware after the built-in middleware (e.g. logging), but before the controller methods.
// The middleware is executed in the order specified. The server will start when "Serve" is called.
func NewWithMiddleware(c Controller, addr string, m []func(http.Handler) http.Handler, options ...func(*serverConfig)) *Server {
	router := newRouter(c)

	return AttachMiddleware(router, addr, m, options...)
}

// AttachMiddleware attaches the given middleware to the router; this is to be used in conjunction with
// NewServer. It attaches custom middleware passed as arguments as well as the built-in middleware for
// logging, tracing, and handling panics. It should be noted that the built-in middleware executes first
// followed by the passed in middleware (in the order specified).
func AttachMiddleware(router *mux.Router, addr string, m []func(http.Handler) http.Handler, options ...func(*serverConfig)) *Server {
	// Set sane defaults, to be overriden by the varargs functions.
	// This would probably be better done in NewWithMiddleware, but there are services that call
	// AttachMiddleWare directly instead.
	config := serverConfig{
		compressionLevel: gzip.DefaultCompression,
	}
	for _, option := range options {
		option(&config)
	}

	l := logger.New("swagger-test")

	handler := withMiddleware("swagger-test", router, m, config)
	return &Server{Handler: handler, addr: addr, l: l, config: config}
}