Add a new OpenAPI v3 REST API to warewulfd at /api

Co-authored-by: jason yang <jasonyangshadow@gmail.com>

Signed-off-by: Jonathon Anderson <janderson@ciq.com>

internal/pkg/warewulfd/server/server.go

@@ -0,0 +1,90 @@
+package server
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+	"os/signal"
+	"strconv"
+	"strings"
+	"syscall"
+
+	warewulfconf "github.com/warewulf/warewulf/internal/pkg/config"
+	"github.com/warewulf/warewulf/internal/pkg/util"
+	"github.com/warewulf/warewulf/internal/pkg/warewulfd"
+	"github.com/warewulf/warewulf/internal/pkg/warewulfd/api"
+	"github.com/warewulf/warewulf/internal/pkg/wwlog"
+)
+
+// TODO: https://github.com/danderson/netboot/blob/master/pixiecore/dhcp.go
+// TODO: https://github.com/pin/tftp
+/*
+wrapper type for the server mux as shim requests http://efiboot//grub.efi
+which is filtered out by http to `301 Moved Permanently` what
+shim.efi can't handle. So filter out `//` before they hit go/http.
+Makes go/http more to behave like apache
+*/
+type slashFix struct {
+	mux http.Handler
+}
+
+/*
+Filter out the '//'
+*/
+func (h *slashFix) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	r.URL.Path = strings.Replace(r.URL.Path, "//", "/", -1)
+	h.mux.ServeHTTP(w, r)
+}
+
+func defaultHandler() *slashFix {
+	var wwHandler http.ServeMux
+	wwHandler.HandleFunc("/provision/", warewulfd.ProvisionSend)
+	wwHandler.HandleFunc("/ipxe/", warewulfd.ProvisionSend)
+	wwHandler.HandleFunc("/efiboot/", warewulfd.ProvisionSend)
+	wwHandler.HandleFunc("/kernel/", warewulfd.ProvisionSend)
+	wwHandler.HandleFunc("/container/", warewulfd.ProvisionSend)
+	wwHandler.HandleFunc("/overlay-system/", warewulfd.ProvisionSend)
+	wwHandler.HandleFunc("/overlay-runtime/", warewulfd.ProvisionSend)
+	wwHandler.HandleFunc("/overlay-file/", warewulfd.OverlaySend)
+	wwHandler.HandleFunc("/status", warewulfd.StatusSend)
+	return &slashFix{&wwHandler}
+}
+
+func RunServer() error {
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, syscall.SIGHUP)
+
+	go func() {
+		for range c {
+			wwlog.Info("Received SIGHUP, reloading...")
+			warewulfd.Reload()
+		}
+	}()
+
+	warewulfd.Reload()
+
+	conf := warewulfconf.Get()
+	daemonPort := conf.Warewulf.Port
+
+	auth := warewulfconf.NewAuthentication()
+	if util.IsFile(conf.Paths.AuthenticationConf()) {
+		if err := auth.Read(conf.Paths.AuthenticationConf()); err != nil {
+			wwlog.Warn("%w\n", err)
+		}
+	}
+
+	apiHandler := api.Handler(auth, conf.API.AllowedIPNets())
+	defaultHandler := defaultHandler()
+	dispatchHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if strings.HasPrefix(r.URL.Path, "/api") && conf.API != nil && conf.API.Enabled() {
+			apiHandler.ServeHTTP(w, r)
+		} else {
+			defaultHandler.ServeHTTP(w, r)
+		}
+	})
+	if err := http.ListenAndServe(":"+strconv.Itoa(daemonPort), dispatchHandler); err != nil {
+		return fmt.Errorf("could not start listening service: %w", err)
+	}
+
+	return nil
+}