18F/e-QIP-prototype

package http

import (
    "crypto/tls"
    "net/http"

    "github.com/18F/e-QIP-prototype/api"
)

var (
    // TransportLayerSecurity is the TLS configuration settings for a HTTPS server.
    TransportLayerSecurity = &tls.Config{
        MinVersion: tls.VersionTLS12,
        CurvePreferences: []tls.CurveID{
            tls.CurveP521,
            tls.CurveP384,
            tls.CurveP256,
        },
        PreferServerCipherSuites: true,
        CipherSuites: []uint16{
            tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
            tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
            tls.TLS_RSA_WITH_AES_256_GCM_SHA384,
            tls.TLS_RSA_WITH_AES_256_CBC_SHA,
        },
    }
)

// Server is a HTTP/HTTPS server implementation.
type Server struct {
    Env api.Settings
    Log api.LogService
}

type serverFunc func(server *http.Server) error

// ListenAndServe will bind to the host address and port and serve the content.
func (service Server) ListenAndServe(address string, router http.Handler) error {
    var message string
    var server *http.Server
    var serverFunc serverFunc

    if service.Env.Has(api.TLSCert) && service.Env.Has(api.TLSKey) {
        message = api.StartingServerTLS
        server = &http.Server{
            Addr:         address,
            Handler:      router,
            TLSConfig:    TransportLayerSecurity,
            TLSNextProto: make(map[string]func(*http.Server, *tls.Conn, http.Handler), 0),
        }
        serverFunc = func(s *http.Server) error {
            return s.ListenAndServeTLS(service.Env.String(api.TLSCert), service.Env.String(api.TLSKey))
        }
    } else {
        message = api.StartingServer
        server = &http.Server{
            Addr:    address,
            Handler: router,
        }
        serverFunc = func(s *http.Server) error {
            return s.ListenAndServe()
        }
    }

    service.Log.Info(message, api.LogFields{"address": address})
    return serverFunc(server)
}