Added server implementation and serve command

internal/server/server.go

@@ -0,0 +1,105 @@
+//go:build server || all
+// +build server all
+
+package server
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+
+	configurator "github.com/OpenCHAMI/configurator/internal"
+	"github.com/OpenCHAMI/configurator/internal/generator"
+	"github.com/OpenCHAMI/jwtauth/v5"
+	"github.com/go-chi/chi/v5"
+	"github.com/go-chi/chi/v5/middleware"
+	"github.com/sirupsen/logrus"
+)
+
+var (
+	tokenAuth *jwtauth.JWTAuth = nil
+)
+
+type Server struct {
+	*http.Server
+}
+
+func New() *Server {
+	return &Server{
+		Server: &http.Server{},
+	}
+}
+
+func (s *Server) Start(config *configurator.Config) error {
+	// create client just for the server to use to fetch data from SMD
+	client := &configurator.SmdClient{
+		Host: config.SmdHost,
+		Port: config.SmdPort,
+	}
+
+	// set the server address with config values
+	s.Server.Addr = fmt.Sprintf("%s:%d", config.Server.Host, config.Server.Port)
+
+	// fetch JWKS public key from authorization server
+	if config.Options.JwksUri != "" && tokenAuth == nil {
+		for i := 0; i < config.Options.JwksRetries; i++ {
+			var err error
+			tokenAuth, err = configurator.FetchPublicKeyFromURL(config.Options.JwksUri)
+			if err != nil {
+				logrus.Errorf("failed to fetch JWKS: %w", err)
+				continue
+			}
+			break
+		}
+	}
+
+	// create new go-chi router with its routes
+	router := chi.NewRouter()
+	router.Use(middleware.RedirectSlashes)
+	router.Use(middleware.Timeout(60 * time.Second))
+	router.Group(func(r chi.Router) {
+		if config.Options.JwksUri != "" {
+			r.Use(
+				jwtauth.Verifier(tokenAuth),
+				jwtauth.Authenticator(tokenAuth),
+			)
+		}
+		r.HandleFunc("/target", func(w http.ResponseWriter, r *http.Request) {
+			g := generator.Generator{
+				Type:     r.URL.Query().Get("type"),
+				Template: r.URL.Query().Get("template"),
+			}
+
+			// NOTE: we probably don't want to hardcode the types, but should do for now
+			if g.Type == "dhcp" {
+				// fetch eths from SMD
+				eths, err := client.FetchEthernetInterfaces()
+				if err != nil {
+					logrus.Errorf("failed to fetch DHCP metadata: %v\n", err)
+					w.Write([]byte("An error has occurred"))
+					return
+				}
+				if len(eths) <= 0 {
+					logrus.Warnf("no ethernet interfaces found")
+					w.Write([]byte("no ethernet interfaces found"))
+					return
+				}
+				// generate a new config from that data
+
+				err = g.GenerateDHCP(config, eths)
+				if err != nil {
+					logrus.Errorf("failed to generate DHCP: %v", err)
+					w.Write([]byte("An error has occurred."))
+					return
+				}
+			}
+		})
+		r.HandleFunc("/templates", func(w http.ResponseWriter, r *http.Request) {
+			// TODO: handle GET request
+			// TODO: handle POST request
+
+		})
+	})
+	s.Handler = router
+	return s.ListenAndServe()
+}