Merge pull request #2 from messagebird/udp-disconnect-bug

Don't return, but continue, on a UDP error

.travis.yml

@@ -0,0 +1,10 @@
+language: go
+
+go:
+  - 1.4
+  - 1.5
+  - 1.6
+  - 1.7
+  - tip
+
+script: make test

Makefile

@@ -43,14 +43,6 @@ container: release_linux
 test:
 	@echo "* Running tests"
 	@$(GO) test $(PROJECT)/...
-	@echo
-
-	@echo "* Checking code with golint"
-	@golint src/$(PROJECT)/...
-	@echo
-
-	@echo "* Checking code with go vet"
-	@$(GO) vet $(PROJECT)/...
 
 clean:
 	rm -fr bin pkg vendor/pkg

README.md

@@ -1,6 +1,8 @@
 
 # Pushprom
 
+[![Build Status](https://travis-ci.org/messagebird/pushprom.svg?branch=master)](https://travis-ci.org/messagebird/pushprom)
+
 Pushprom is a proxy (HTTP/UDP) to the [Prometheus](https://prometheus.io/) Go client.
 
 Prometheus doesn't offer a PHP client and PHP clients are hard to implement because they would need to keep track of state and PHP setups generally don't encourage that. That's why we built Pushprom.

src/pushprom/udp.go

@@ -25,7 +25,7 @@ func listenUDP() {
 		n, _, err := serverConn.ReadFromUDP(buf)
 		if err != nil {
 			log.Println("Error: ", err)
-			return
+			continue
 		}
 		udpPacketCount.Inc()
 		if *debug {
@@ -34,13 +34,12 @@ func listenUDP() {
 		delta, err := NewDelta(bytes.NewBuffer(buf[0:n]))
 		if err != nil {
 			log.Println("Error: ", err)
-			return
+			continue
 		}
 
 		err = delta.Apply()
 		if err != nil {
 			log.Println("Error: ", err)
 		}
-
 	}
 }

src/pushprom/udp_test.go

@@ -2,32 +2,46 @@ package main
 
 import (
 	"encoding/json"
+	"log"
 	"net"
+	"os"
 	"testing"
 	"time"
 
 	"github.com/stretchr/testify/assert"
 )
 
-func TestUDP(t *testing.T) {
+var conn *net.UDPConn
 
+func TestMain(m *testing.M) {
 	*udpListenAddress = ":3007"
+
 	go listenUDP()
 
 	// wait for it to "boot"
 	time.Sleep(time.Millisecond * 1000)
 
 	serverAddr, err := net.ResolveUDPAddr("udp", "127.0.0.1"+*udpListenAddress)
-	assert.Nil(t, err)
+	if err != nil {
+		log.Fatal("Could not resolve server UPD address")
+	}
 
 	localAddr, err := net.ResolveUDPAddr("udp", "127.0.0.1:0")
-	assert.Nil(t, err)
+	if err != nil {
+		log.Fatal("Could not resolve local UDP address")
+	}
 
-	conn, err := net.DialUDP("udp", localAddr, serverAddr)
-	assert.Nil(t, err)
+	conn, err = net.DialUDP("udp", localAddr, serverAddr)
+	if err != nil {
+		log.Fatal("Could not establish UDP connection")
+	}
 
 	defer conn.Close()
 
+	os.Exit(m.Run())
+}
+
+func TestUDP(t *testing.T) {
 	delta := &Delta{
 		Type:   GAUGE,
 		Method: "set",
@@ -38,7 +52,7 @@ func TestUDP(t *testing.T) {
 
 	buf, _ := json.Marshal(delta)
 
-	_, err = conn.Write(buf)
+	_, err := conn.Write(buf)
 	assert.Nil(t, err)
 
 	time.Sleep(time.Millisecond * 500)
@@ -49,3 +63,49 @@ func TestUDP(t *testing.T) {
 		assert.Equal(t, delta.Value, result)
 	}
 }
+
+func TestIncorrectJson(t *testing.T) {
+	// First, let's write the correct value
+	oldDelta := &Delta{
+		Type:   GAUGE,
+		Method: "set",
+		Name:   "tree_width",
+		Help:   "the width in meters of the tree",
+		Value:  2.2,
+	}
+	buf, _ := json.Marshal(oldDelta)
+
+	_, err := conn.Write(buf)
+	assert.Nil(t, err)
+
+	oldMetrics := fetchMetrics(t)
+	oldResult, err := readMetric(oldMetrics, oldDelta.Name, oldDelta.Labels)
+	if assert.Nil(t, err) {
+		assert.Equal(t, oldDelta.Value, oldResult)
+	}
+
+	// Now, let's write the incorrect value
+	buf = []byte("hello")
+
+	_, err = conn.Write(buf)
+	assert.Nil(t, err)
+
+	// Last, let's write a new value
+	newDelta := &Delta{
+		Type:   GAUGE,
+		Method: "set",
+		Name:   "tree_width",
+		Help:   "the width in meters of the tree",
+		Value:  2.5,
+	}
+	buf, _ = json.Marshal(newDelta)
+
+	_, err = conn.Write(buf)
+	assert.Nil(t, err)
+
+	newMetrics := fetchMetrics(t)
+	newResult, err := readMetric(newMetrics, newDelta.Name, newDelta.Labels)
+	if assert.Nil(t, err) {
+		assert.Equal(t, newDelta.Value, newResult)
+	}
+}