Localise all external resources so that application can be used without requiring clearnet connectivity

Add gzip handler so that assets can be compressed if clients request it
Add cache-control headers so that content can be effectively cached locally

StaticRoot/index.html

@@ -4,8 +4,9 @@
   <title>DN42 Registry Explorer</title>
   <meta charset="utf-8">
   <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
-  <link rel="stylesheet" href="bootstrap.min.css">
-  <link rel="stylesheet" href="https://fonts.googleapis.com/icon?family=Material+Icons">
+  <link rel="icon" type="image/png" href="favicon.png"/>
+  <link rel="stylesheet" href="bootstrap.min.css"/>
+  <link rel="stylesheet" href="material-icons.css"/>
 <!-- Style overrides -->  
   <style>
 .material-icons { display:inline-flex;vertical-align:middle }
@@ -205,13 +206,12 @@ body { box-shadow: inset 0 2em 10em rgba(0,0,0,0.4); min-height: 100vh }
 </span>
 </script>
 
-<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
-<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.2.1/js/bootstrap.min.js" integrity="sha384-B0UglyR+jN6CkvvICOB2joaf5I4l3gm9GU6Hc1og6Ls7i6U/mkkaduKaBhlAXv9k" crossorigin="anonymous"></script>
-<script src="https://unpkg.com/vue"></script -->
-<script src="https://unpkg.com/vue-router"></script -->
-<script src="https://unpkg.com/axios@0.18.0/dist/axios.min.js"></script>
-<!-- script src="https://unpkg.com/vue@2.6.2/dist/vue.min.js"></script -->
-<!-- script src="https://unpkg.com/vue-router@3.0.2/dist/vue-router.js"></script -->
+<script src="jquery.slim.min.js"></script>
+<script src="bootstrap.bundle.min.js"></script>
+<script src="vue.min.js"></script>
+<script src="vue-router.min.js"></script>
+<script src="axios.min.js"></script>
+<script src="anchorme.min.js"></script>
 <script src="anchorme.min.js"></script>
 <script src="explorer.js"></script>
 </body>

StaticRoot/material-icons.css

@@ -0,0 +1,20 @@
+@font-face {
+  font-family: 'Material Icons';
+  font-style: normal;
+  font-weight: 400;
+  src: url(/material-icons.ttf) format('truetype');
+}
+
+.material-icons {
+  font-family: 'Material Icons';
+  font-weight: normal;
+  font-style: normal;
+  font-size: 24px;
+  line-height: 1;
+  letter-spacing: normal;
+  text-transform: none;
+  display: inline-block;
+  white-space: nowrap;
+  word-wrap: normal;
+  direction: ltr;
+}

StaticRoot/source-sans-pro.css

@@ -0,0 +1,6 @@
+@font-face {
+  font-family: 'Source Sans Pro';
+  font-style: normal;
+  font-weight: 400;
+  src: local('Source Sans Pro Regular'), local('SourceSansPro-Regular'), url(source-sans-pro.ttf) format('truetype');
+}

dn42regsrv.go

@@ -9,6 +9,7 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"github.com/gorilla/handlers"
 	"github.com/gorilla/mux"
 	log "github.com/sirupsen/logrus"
 	flag "github.com/spf13/pflag"
@@ -143,8 +144,9 @@ func main() {
 
 	// initialise router
 	router := mux.NewRouter()
-	// log all access
+	// global handers, log all requests and allow compression
 	router.Use(requestLogger)
+	router.Use(handlers.CompressHandler)
 
 	// add API routes
 	subr := router.PathPrefix("/api").Subrouter()

dnsapi.go

@@ -89,6 +89,9 @@ func dnsRZoneHandler(w http.ResponseWriter, r *http.Request) {
 		format = []string{"json"}
 	}
 
+	// cache for up to a day
+	w.Header().Set("Cache-Control", "public, max-age=86400, stale-if-error=86400")
+
 	switch format[0] {
 	case "bind":
 		DNSRootZone.WriteBindFormat(w)

go.mod

@@ -3,6 +3,7 @@ module burble.dn42/dn42regsrv
 go 1.14
 
 require (
+	github.com/gorilla/handlers v1.5.1
 	github.com/gorilla/mux v1.7.4
 	github.com/sirupsen/logrus v1.6.0
 	github.com/spf13/pflag v1.0.5

go.sum

@@ -1,4 +1,8 @@
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/felixge/httpsnoop v1.0.1 h1:lvB5Jl89CsZtGIWuTcDM1E/vkVs49/Ml7JJe07l8SPQ=
+github.com/felixge/httpsnoop v1.0.1/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
+github.com/gorilla/handlers v1.5.1 h1:9lRY6j8DEeeBT10CvO9hGW0gmky0BprnvDI5vfhUHH4=
+github.com/gorilla/handlers v1.5.1/go.mod h1:t8XrUpc4KVXb7HGyJ4/cEnwQiaxrX/hz1Zv/4g96P1Q=
 github.com/gorilla/mux v1.7.4 h1:VuZ8uybHlWmqV03+zRzdwKL4tUnIp1MAQtp1mIFE1bc=
 github.com/gorilla/mux v1.7.4/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB71So=
 github.com/konsorten/go-windows-terminal-sequences v1.0.3/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=

regapi.go

@@ -63,6 +63,8 @@ func regMetaHandler(w http.ResponseWriter, r *http.Request) {
 		Commit: RegistryData.Commit,
 	}
 
+	// don't cache
+	w.Header().Set("Cache-Control", "no-store")
 	ResponseJSON(w, rv)
 }
 
@@ -311,6 +313,11 @@ func regRootHandler(w http.ResponseWriter, r *http.Request) {
 	for _, rType := range RegistryData.Types {
 		response[rType.Ref] = len(rType.Objects)
 	}
+
+	// cache for up to a day, but set etag to commit to catch changes
+	w.Header().Set("Cache-Control", "public, max-age=86400, stale-if-error=86400")
+	w.Header().Set("ETag", RegistryData.Commit)
+
 	ResponseJSON(w, response)
 
 }
@@ -344,6 +351,10 @@ func regTypeHandler(w http.ResponseWriter, r *http.Request) {
 		response[rtype.Ref] = objects
 	}
 
+	// cache for up to a day, but set etag to commit to catch changes
+	w.Header().Set("Cache-Control", "public, max-age=86400, stale-if-error=86400")
+	w.Header().Set("ETag", RegistryData.Commit)
+
 	ResponseJSON(w, response)
 }
 
@@ -409,6 +420,10 @@ func regObjectHandler(w http.ResponseWriter, r *http.Request) {
 			}
 		}
 
+		// cache for up to a day, but set etag to commit to catch changes
+		w.Header().Set("Cache-Control", "public, max-age=86400, stale-if-error=86400")
+		w.Header().Set("ETag", RegistryData.Commit)
+
 		ResponseJSON(w, response)
 
 	} else {
@@ -427,6 +442,10 @@ func regObjectHandler(w http.ResponseWriter, r *http.Request) {
 			}
 		}
 
+		// cache for up to a day, but set etag to commit to catch changes
+		w.Header().Set("Cache-Control", "public, max-age=86400, stale-if-error=86400")
+		w.Header().Set("ETag", RegistryData.Commit)
+
 		ResponseJSON(w, response)
 	}
 
@@ -478,6 +497,10 @@ func regKeyHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// cache for up to a day, but set etag to commit to catch changes
+	w.Header().Set("Cache-Control", "public, max-age=86400, stale-if-error=86400")
+	w.Header().Set("ETag", RegistryData.Commit)
+
 	ResponseJSON(w, amap)
 }
 
@@ -528,6 +551,10 @@ func regAttributeHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// cache for up to a day, but set etag to commit to catch changes
+	w.Header().Set("Cache-Control", "public, max-age=86400, stale-if-error=86400")
+	w.Header().Set("ETag", RegistryData.Commit)
+
 	ResponseJSON(w, amap)
 
 }

roaapi.go

@@ -130,6 +130,10 @@ func roaFilterHandler(w http.ResponseWriter, r *http.Request) {
 		filters = fselect(filters, 6)
 	}
 
+	// cache for up to a week, but set etag to commit to catch changes
+	w.Header().Set("Cache-Control", "public, max-age=604800, stale-if-error=86400")
+	w.Header().Set("ETag", ROAData.Commit)
+
 	ResponseJSON(w, filters)
 }
 
@@ -147,6 +151,10 @@ func roaJSONHandler(w http.ResponseWriter, r *http.Request) {
 		ROAJSONResponse.MetaData.Valid += (ROA_JSON_VALIDITY_PERIOD * 3600)
 	}
 
+	// cache for up to a week, but set etag to commit to catch changes
+	w.Header().Set("Cache-Control", "public, max-age=604800, stale-if-error=86400")
+	w.Header().Set("ETag", ROAData.Commit)
+
 	ResponseJSON(w, ROAJSONResponse)
 }
 
@@ -174,6 +182,10 @@ func roaBirdHandler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "text/plain")
 	w.Header().Set("Access-Control-Allow-Origin", "*")
 
+	// cache for up to a week, but set etag to commit to catch changes
+	w.Header().Set("Cache-Control", "public, max-age=604800, stale-if-error=86400")
+	w.Header().Set("ETag", ROAData.Commit)
+
 	fmt.Fprintf(w, "#\n# dn42regsrv ROA Generator\n# Last Updated: %s\n"+
 		"# Commit: %s\n#\n", ROAData.CTime.String(), ROAData.Commit)
 

static.go

@@ -42,8 +42,7 @@ func InstallStaticRoutes(router *mux.Router, staticPath string) {
 	}
 
 	// install a file server for the static route
-	router.PathPrefix("/").Handler(http.StripPrefix("/",
-		http.FileServer(http.Dir(staticPath)))).Methods("GET")
+	router.PathPrefix("/").Handler(staticHandler(staticPath))
 
 	log.WithFields(log.Fields{
 		"path": staticPath,
@@ -51,5 +50,18 @@ func InstallStaticRoutes(router *mux.Router, staticPath string) {
 
 }
 
+//////////////////////////////////////////////////////////////////////////
+
+func staticHandler(path string) http.Handler {
+
+	server := http.FileServer(http.Dir(path))
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// allow up to a month of caching
+		w.Header().Set("Cache-Control", "public, max-age=2592000, stale-if-error=86400")
+		server.ServeHTTP(w, r)
+	})
+}
+
 //////////////////////////////////////////////////////////////////////////
 // end of code