fix context timout

daemon.go

@@ -166,7 +166,7 @@ func (d *daemon) runCheck(query url.Values) (*output, error) {
 		connErr := testHost.Connect(dialCtx, *ai)
 		dialCancel()
 		if connErr != nil {
-			out.ConnectionError = connErr.Error()
+			out.ConnectionError = fmt.Sprintf("error dialing to peer: %s", connErr.Error())
 			connectionFailed = true
 		}
 	}
@@ -175,17 +175,17 @@ func (d *daemon) runCheck(query url.Values) (*output, error) {
 		out.DataAvailableOverBitswap.Error = "could not connect to peer"
 	} else {
 		// If so is the data available over Bitswap?
-		out.DataAvailableOverBitswap = checkBitswapCID(ctx, c, ma)
+		out.DataAvailableOverBitswap = checkBitswapCID(ctx, testHost, c, ma)
 	}
 
 	return out, nil
 }
 
-func checkBitswapCID(ctx context.Context, c cid.Cid, ma multiaddr.Multiaddr) BitswapCheckOutput {
+func checkBitswapCID(ctx context.Context, host host.Host, c cid.Cid, ma multiaddr.Multiaddr) BitswapCheckOutput {
 	out := BitswapCheckOutput{}
 	start := time.Now()
 
-	bsOut, err := vole.CheckBitswapCID(ctx, c, ma, false)
+	bsOut, err := vole.CheckBitswapCID(ctx, host, c, ma, false)
 	if err != nil {
 		out.Error = err.Error()
 	} else {

main.go

@@ -8,6 +8,9 @@ import (
 	"net/http"
 	"os"
 
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+
 	"github.com/urfave/cli/v2"
 )
 
@@ -50,17 +53,16 @@ func startServer(ctx context.Context, d *daemon, tcpListener string) error {
 		return err
 	}
 
+	log.Printf("listening on %v\n", l.Addr())
+	log.Printf("Libp2p host peer id %s\n", d.h.ID())
+	log.Printf("Libp2p host listening on %v\n", d.h.Addrs())
 	log.Printf("listening on %v\n", l.Addr())
 
 	d.mustStart()
 
 	log.Printf("ready to start serving")
 
-	// 1. Is the peer findable in the DHT?
-	// 2. Does the multiaddr work? If not, what's the error?
-	// 3. Is the CID in the DHT?
-	// 4. Does the peer respond that it has the given data over Bitswap?
-	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+	checkHandler := func(w http.ResponseWriter, r *http.Request) {
 		w.Header().Add("Access-Control-Allow-Origin", "*")
 		data, err := d.runCheck(r.URL.Query())
 		if err == nil {
@@ -70,8 +72,60 @@ func startServer(ctx context.Context, d *daemon, tcpListener string) error {
 			w.WriteHeader(http.StatusInternalServerError)
 			_, _ = w.Write([]byte(err.Error()))
 		}
+	}
+
+	// Create a custom registry
+	reg := prometheus.NewRegistry()
+
+	requestsTotal := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "http_requests_total",
+			Help: "Total number of slow requests",
+		},
+		[]string{"code"},
+	)
+
+	requestDuration := prometheus.NewHistogramVec(
+		prometheus.HistogramOpts{
+			Name:    "http_request_duration_seconds",
+			Help:    "Duration of slow requests",
+			Buckets: prometheus.DefBuckets,
+		},
+		[]string{"code"},
+	)
+
+	requestsInFlight := prometheus.NewGauge(prometheus.GaugeOpts{
+		Name: "slow_requests_in_flight",
+		Help: "Number of slow requests currently being served",
 	})
 
+	// Register metrics with our custom registry
+	reg.MustRegister(requestsTotal)
+	reg.MustRegister(requestDuration)
+	reg.MustRegister(requestsInFlight)
+	// Instrument the slowHandler
+	instrumentedHandler := promhttp.InstrumentHandlerCounter(
+		requestsTotal,
+		promhttp.InstrumentHandlerDuration(
+			requestDuration,
+			promhttp.InstrumentHandlerInFlight(
+				requestsInFlight,
+				http.HandlerFunc(checkHandler),
+			),
+		),
+	)
+
+	// 1. Is the peer findable in the DHT?
+	// 2. Does the multiaddr work? If not, what's the error?
+	// 3. Is the CID in the DHT?
+	// 4. Does the peer respond that it has the given data over Bitswap?
+	http.Handle("/check", instrumentedHandler)
+	http.Handle("/debug/libp2p", promhttp.Handler())
+	http.Handle("/debug/http", promhttp.HandlerFor(
+		reg,
+		promhttp.HandlerOpts{},
+	))
+
 	done := make(chan error, 1)
 	go func() {
 		defer close(done)

test/tools.go

@@ -43,7 +43,7 @@ func Query(
 
 	e := httpexpect.Default(t, url)
 
-	return e.POST("/").
+	return e.POST("/check").
 		WithQuery("cid", cid).
 		WithQuery("multiaddr", multiaddr).
 		Expect().

web/index.html

@@ -111,16 +111,22 @@ <h2 class="f4">What does it mean if I get an error?</h2>
             const backendURL = getBackendUrl(formData)
 
             showInQuery(formData) // add `cid` and `multiaddr` to local url query to make it shareable
-            toggleSubmitButton()            
-            const res = await fetch(backendURL, { method: 'POST' })
             toggleSubmitButton()
-            if (res.ok) {
-                const respObj = await res.json()
-                const output = formatOutput(formData, respObj)
-                showOutput(output)
-            } else {
-                const resText = await res.text()
-                showOutput(`⚠️ backend returned an error: ${res.status} ${resText}`)
+            try {
+              const res = await fetch(backendURL, { method: 'POST' })
+
+              if (res.ok) {
+                  const respObj = await res.json()
+                  const output = formatOutput(formData, respObj)
+                  showOutput(output)
+              } else {
+                  const resText = await res.text()
+                  showOutput(`⚠️ backend returned an error: ${res.status} ${resText}`)
+              }
+            } catch (e) {
+              showOutput(`⚠️ backend error: ${e}`)
+            } finally {
+              toggleSubmitButton()
             }
         })
     })
@@ -163,31 +169,33 @@ <h2 class="f4">What does it mean if I get an error?</h2>
     function formatOutput (formData, respObj) {
         const ma = formData.get('multiaddr')
         const peerIDStartIndex = ma.lastIndexOf("/p2p/")
-        const peerID = ma.substr(peerIDStartIndex + 5, ma.length)
-        const addrPart = ma.substr(0, peerIDStartIndex)
+        const peerID = ma.slice(peerIDStartIndex + 5);
+        const addrPart = ma.slice(0, peerIDStartIndex);
         let outText = ""
 
         if (respObj.ConnectionError !== "") {
             outText += "❌ Could not connect to multiaddr: " + respObj.ConnectionError + "\n"
         } else {
-            outText += "✔ Successfully connected to multiaddr\n"
+            outText += "✅ Successfully connected to multiaddr\n"
         }
 
         if (ma.indexOf("/p2p/") === 0 && ma.lastIndexOf("/") === 4) {
+            // only peer id passed with /p2p/PeerID
             if (Object.keys(respObj.PeerFoundInDHT).length === 0) {
                 outText += "❌ Could not find any multiaddrs in the dht\n"
             } else {
-                outText += "✔ Found multiaddrs advertised in the DHT:\n"
+                outText += "✅ Found multiaddrs advertised in the DHT:\n"
                 for (const key in respObj.PeerFoundInDHT) {
                     outText += "\t" + key + "\n"
                 }
             }
         } else {
+            // a proper maddr with an IP was passed
             let foundAddr = false
             for (const key in respObj.PeerFoundInDHT) {
                 if (key === addrPart) {
                     foundAddr = true
-                    outText += "✔ Found multiaddr with " + respObj.PeerFoundInDHT[key] + " dht peers\n"
+                    outText += "✅ Found multiaddr with " + respObj.PeerFoundInDHT[key] + " dht peers\n"
                     break
                 }
             }
@@ -200,7 +208,7 @@ <h2 class="f4">What does it mean if I get an error?</h2>
         }
 
         if (respObj.CidInDHT === true) {
-            outText += "✔ Found multihash advertised in the dht\n"
+            outText += "✅ Found multihash advertised in the dht\n"
         } else {
             outText += "❌ Could not find the multihash in the dht\n"
         }
@@ -210,7 +218,7 @@ <h2 class="f4">What does it mean if I get an error?</h2>
         } else if (respObj.DataAvailableOverBitswap.Responded !== true) {
             outText += "❌ The peer did not quickly respond if it had the CID\n"
         } else if (respObj.DataAvailableOverBitswap.Found === true) {
-            outText += "✔ The peer responded that it has the CID\n"
+            outText += "✅ The peer responded that it has the CID\n"
         } else {
             outText += "❌ The peer responded that it does not have the CID\n"
         }