cmd/serve: Add (terrible) prototype for server

Yes, it's ugly. Yes, goroutines have no way of exiting. But it solves
the need for getting this exposed via http, and periodically refreshing
the data within it. Please do not use it!

cmd/serve.go

@@ -0,0 +1,197 @@
+package cmd
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"sort"
+	"sync"
+	"time"
+
+	"github.com/dotwaffle/ovplusplus/pkg/irr"
+	"github.com/dotwaffle/ovplusplus/pkg/pfxops"
+	"github.com/dotwaffle/ovplusplus/pkg/rpki"
+	"github.com/rs/zerolog/log"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+	"golang.org/x/sync/errgroup"
+)
+
+// serveCmd implements the serve command.
+var serveCmd = &cobra.Command{
+	Use:   "serve",
+	Short: "Serve an export.json file based on IRR and RPKI data.",
+	Run: func(cmd *cobra.Command, args []string) {
+		var export string
+		var mu sync.Mutex
+		routes := make(map[string][]irr.Route)
+		var roas []rpki.ROA
+		updated := make(chan bool)
+		defer close(updated)
+
+		go func() {
+			ticker := time.NewTicker(viper.GetDuration("refresh"))
+			defer ticker.Stop()
+			for {
+				ctx, cancel := context.WithTimeout(context.Background(), viper.GetDuration("refresh"))
+				defer cancel()
+				e, eCtx := errgroup.WithContext(ctx)
+
+				var newMu sync.Mutex
+				newRoutes := make(map[string][]irr.Route)
+
+				// for each input, get the data
+				for _, src := range viper.GetStringSlice("file") {
+					src := src
+					e.Go(func() error {
+						srcRoutes, err := irr.FetchFile(eCtx, src)
+						if err != nil {
+							return err
+						}
+						log.Debug().Int("routes", len(srcRoutes)).Str("src", src).Msg("irrdb parsed")
+						newMu.Lock()
+						newRoutes[src] = srcRoutes
+						newMu.Unlock()
+						return nil
+					})
+				}
+
+				for _, src := range viper.GetStringSlice("irrdb") {
+					src := src
+					e.Go(func() error {
+						srcRoutes, err := irr.FetchURL(eCtx, src)
+						if err != nil {
+							return err
+						}
+						log.Debug().Int("routes", len(srcRoutes)).Str("src", src).Msg("irrdb parsed")
+						newMu.Lock()
+						newRoutes[src] = srcRoutes
+						newMu.Unlock()
+						return nil
+					})
+				}
+
+				if err := e.Wait(); err != nil {
+					log.Error().Err(err).Msg("irrdb read")
+					continue
+				}
+
+				mu.Lock()
+				routes = newRoutes
+				mu.Unlock()
+				updated <- true
+
+				// wait for tick
+				<-ticker.C
+			}
+		}()
+
+		go func() {
+			ticker := time.NewTicker(viper.GetDuration("refresh"))
+			defer ticker.Stop()
+			for {
+				ctx, cancel := context.WithTimeout(context.Background(), viper.GetDuration("refresh"))
+				defer cancel()
+
+				// import RPKI ROA export
+				newROAs, err := rpki.Fetch(ctx, viper.GetString("rpki"))
+				if err != nil {
+					log.Error().Err(err).Msg("rpki.Fetch()")
+					continue
+				}
+
+				mu.Lock()
+				roas = newROAs
+				log.Debug().Int("roas", len(roas)).Msg("rpki parsed")
+				mu.Unlock()
+				updated <- true
+
+				<-ticker.C
+			}
+		}()
+
+		go func() {
+			for range updated {
+				mu.Lock()
+				// merge data
+				results, err := pfxops.Merge(roas, routes)
+				if err != nil {
+					log.Error().Err(err).Msg("pfxops.Merge()")
+					mu.Unlock()
+					continue
+				}
+				sort.SliceStable(results, func(i, j int) bool {
+					switch {
+					case results[i].ASN < results[j].ASN:
+						return true
+					case results[i].ASN > results[j].ASN:
+						return false
+					case results[i].MaxLength < results[j].MaxLength:
+						return true
+					case results[i].MaxLength > results[j].MaxLength:
+						return false
+					case results[i].Prefix < results[j].Prefix:
+						return true
+					case results[i].Prefix > results[j].Prefix:
+						return false
+					case results[i].TA < results[j].TA:
+						return true
+					case results[i].TA > results[j].TA:
+						return false
+					default:
+						return false
+					}
+				})
+				log.Debug().Int("roas", len(results)).Msg("new total roas")
+
+				// prepare the output
+				output, err := json.MarshalIndent(rpki.Export{ROAs: results}, "", "\t")
+				if err != nil {
+					log.Error().Err(err).Msg("json.Marshal()")
+					mu.Unlock()
+					continue
+				}
+				export = string(output)
+				mu.Unlock()
+			}
+		}()
+
+		// serve the data
+		httpExport := func(w http.ResponseWriter, req *http.Request) {
+			fmt.Fprintf(w, export)
+		}
+		http.HandleFunc("/export.json", httpExport)
+		if err := http.ListenAndServe(":8080", nil); err != nil {
+			log.Fatal().Err(err).Msg("http.ListenAndServe()")
+		}
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(serveCmd)
+
+	// fetch IRR data from a URL
+	serveCmd.Flags().StringSliceP("irrdb", "i", []string{}, "url to fetch containing IRRDB data")
+	if err := viper.BindPFlag("irrdb", serveCmd.Flags().Lookup("irrdb")); err != nil {
+		log.Fatal().Err(err).Msg("viper.BindPFlag(): irrdb")
+	}
+
+	// fetch IRR data from a local file
+	serveCmd.Flags().StringSliceP("file", "f", []string{}, "local file containing IRRDB data")
+	if err := viper.BindPFlag("file", serveCmd.Flags().Lookup("file")); err != nil {
+		log.Fatal().Err(err).Msg("viper.BindPFlag(): file")
+	}
+
+	// fetch RPKI data from a URL
+	serveCmd.Flags().StringP("rpki", "r", "", "url to fetch containing RPKI ROA data")
+	if err := viper.BindPFlag("rpki", serveCmd.Flags().Lookup("rpki")); err != nil {
+		log.Fatal().Err(err).Msg("viper.BindPFlag(): rpki")
+	}
+
+	// refresh interval
+	serveCmd.Flags().DurationP("refresh", "R", time.Hour, "interval between refreshing external data")
+	if err := viper.BindPFlag("refresh", serveCmd.Flags().Lookup("refresh")); err != nil {
+		log.Fatal().Err(err).Msg("viper.BindPFlag(): refresh")
+	}
+}