Use random port in http_listener tests

plugins/inputs/http_listener/http_listener.go

@@ -35,6 +35,7 @@ type HTTPListener struct {
 	WriteTimeout   internal.Duration
 	MaxBodySize    int64
 	MaxLineSize    int
+	Port           int
 
 	mu sync.Mutex
 	wg sync.WaitGroup
@@ -124,6 +125,7 @@ func (h *HTTPListener) Start(acc telegraf.Accumulator) error {
 		return err
 	}
 	h.listener = listener
+	h.Port = listener.Addr().(*net.TCPAddr).Port
 
 	h.wg.Add(1)
 	go func() {

plugins/inputs/http_listener/http_listener_test.go

@@ -4,6 +4,8 @@ import (
 	"bytes"
 	"io/ioutil"
 	"net/http"
+	"net/url"
+	"strconv"
 	"sync"
 	"testing"
 
@@ -30,11 +32,21 @@ cpu_load_short,host=server06 value=12.0 1422568543702900257
 
 func newTestHTTPListener() *HTTPListener {
 	listener := &HTTPListener{
-		ServiceAddress: ":8186",
+		ServiceAddress: ":0",
 	}
 	return listener
 }
 
+func createURL(listener *HTTPListener, path string, rawquery string) string {
+	u := url.URL{
+		Scheme:   "http",
+		Host:     "localhost:" + strconv.Itoa(listener.Port),
+		Path:     path,
+		RawQuery: rawquery,
+	}
+	return u.String()
+}
+
 func TestWriteHTTP(t *testing.T) {
 	listener := newTestHTTPListener()
 
@@ -43,7 +55,7 @@ func TestWriteHTTP(t *testing.T) {
 	defer listener.Stop()
 
 	// post single message to listener
-	resp, err := http.Post("http://localhost:8186/write?db=mydb", "", bytes.NewBuffer([]byte(testMsg)))
+	resp, err := http.Post(createURL(listener, "/write", "db=mydb"), "", bytes.NewBuffer([]byte(testMsg)))
 	require.NoError(t, err)
 	require.EqualValues(t, 204, resp.StatusCode)
 
@@ -54,7 +66,7 @@ func TestWriteHTTP(t *testing.T) {
 	)
 
 	// post multiple message to listener
-	resp, err = http.Post("http://localhost:8186/write?db=mydb", "", bytes.NewBuffer([]byte(testMsgs)))
+	resp, err = http.Post(createURL(listener, "/write", "db=mydb"), "", bytes.NewBuffer([]byte(testMsgs)))
 	require.NoError(t, err)
 	require.EqualValues(t, 204, resp.StatusCode)
 
@@ -69,7 +81,7 @@ func TestWriteHTTP(t *testing.T) {
 	}
 
 	// Post a gigantic metric to the listener and verify that an error is returned:
-	resp, err = http.Post("http://localhost:8186/write?db=mydb", "", bytes.NewBuffer([]byte(hugeMetric)))
+	resp, err = http.Post(createURL(listener, "/write", "db=mydb"), "", bytes.NewBuffer([]byte(hugeMetric)))
 	require.NoError(t, err)
 	require.EqualValues(t, 400, resp.StatusCode)
 
@@ -89,7 +101,7 @@ func TestWriteHTTPNoNewline(t *testing.T) {
 	defer listener.Stop()
 
 	// post single message to listener
-	resp, err := http.Post("http://localhost:8186/write?db=mydb", "", bytes.NewBuffer([]byte(testMsgNoNewline)))
+	resp, err := http.Post(createURL(listener, "/write", "db=mydb"), "", bytes.NewBuffer([]byte(testMsgNoNewline)))
 	require.NoError(t, err)
 	require.EqualValues(t, 204, resp.StatusCode)
 
@@ -102,7 +114,7 @@ func TestWriteHTTPNoNewline(t *testing.T) {
 
 func TestWriteHTTPMaxLineSizeIncrease(t *testing.T) {
 	listener := &HTTPListener{
-		ServiceAddress: ":8296",
+		ServiceAddress: ":0",
 		MaxLineSize:    128 * 1000,
 	}
 
@@ -111,14 +123,14 @@ func TestWriteHTTPMaxLineSizeIncrease(t *testing.T) {
 	defer listener.Stop()
 
 	// Post a gigantic metric to the listener and verify that it writes OK this time:
-	resp, err := http.Post("http://localhost:8296/write?db=mydb", "", bytes.NewBuffer([]byte(hugeMetric)))
+	resp, err := http.Post(createURL(listener, "/write", "db=mydb"), "", bytes.NewBuffer([]byte(hugeMetric)))
 	require.NoError(t, err)
 	require.EqualValues(t, 204, resp.StatusCode)
 }
 
 func TestWriteHTTPVerySmallMaxBody(t *testing.T) {
 	listener := &HTTPListener{
-		ServiceAddress: ":8297",
+		ServiceAddress: ":0",
 		MaxBodySize:    4096,
 	}
 
@@ -126,14 +138,14 @@ func TestWriteHTTPVerySmallMaxBody(t *testing.T) {
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
-	resp, err := http.Post("http://localhost:8297/write", "", bytes.NewBuffer([]byte(hugeMetric)))
+	resp, err := http.Post(createURL(listener, "/write", ""), "", bytes.NewBuffer([]byte(hugeMetric)))
 	require.NoError(t, err)
 	require.EqualValues(t, 413, resp.StatusCode)
 }
 
 func TestWriteHTTPVerySmallMaxLineSize(t *testing.T) {
 	listener := &HTTPListener{
-		ServiceAddress: ":8298",
+		ServiceAddress: ":0",
 		MaxLineSize:    70,
 	}
 
@@ -141,7 +153,7 @@ func TestWriteHTTPVerySmallMaxLineSize(t *testing.T) {
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
-	resp, err := http.Post("http://localhost:8298/write", "", bytes.NewBuffer([]byte(testMsgs)))
+	resp, err := http.Post(createURL(listener, "/write", ""), "", bytes.NewBuffer([]byte(testMsgs)))
 	require.NoError(t, err)
 	require.EqualValues(t, 204, resp.StatusCode)
 
@@ -158,7 +170,7 @@ func TestWriteHTTPVerySmallMaxLineSize(t *testing.T) {
 
 func TestWriteHTTPLargeLinesSkipped(t *testing.T) {
 	listener := &HTTPListener{
-		ServiceAddress: ":8300",
+		ServiceAddress: ":0",
 		MaxLineSize:    100,
 	}
 
@@ -166,7 +178,7 @@ func TestWriteHTTPLargeLinesSkipped(t *testing.T) {
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
-	resp, err := http.Post("http://localhost:8300/write", "", bytes.NewBuffer([]byte(hugeMetric+testMsgs)))
+	resp, err := http.Post(createURL(listener, "/write", ""), "", bytes.NewBuffer([]byte(hugeMetric+testMsgs)))
 	require.NoError(t, err)
 	require.EqualValues(t, 400, resp.StatusCode)
 
@@ -183,9 +195,7 @@ func TestWriteHTTPLargeLinesSkipped(t *testing.T) {
 
 // test that writing gzipped data works
 func TestWriteHTTPGzippedData(t *testing.T) {
-	listener := &HTTPListener{
+	listener := newTestHTTPListener()
-		ServiceAddress: ":8299",
-	}
 
 	acc := &testutil.Accumulator{}
 	require.NoError(t, listener.Start(acc))
@@ -194,7 +204,7 @@ func TestWriteHTTPGzippedData(t *testing.T) {
 	data, err := ioutil.ReadFile("./testdata/testmsgs.gz")
 	require.NoError(t, err)
 
-	req, err := http.NewRequest("POST", "http://localhost:8299/write", bytes.NewBuffer(data))
+	req, err := http.NewRequest("POST", createURL(listener, "/write", ""), bytes.NewBuffer(data))
 	require.NoError(t, err)
 	req.Header.Set("Content-Encoding", "gzip")
 
@@ -216,7 +226,7 @@ func TestWriteHTTPGzippedData(t *testing.T) {
 
 // writes 25,000 metrics to the listener with 10 different writers
 func TestWriteHTTPHighTraffic(t *testing.T) {
-	listener := &HTTPListener{ServiceAddress: ":8286"}
+	listener := newTestHTTPListener()
 
 	acc := &testutil.Accumulator{}
 	require.NoError(t, listener.Start(acc))
@@ -229,7 +239,7 @@ func TestWriteHTTPHighTraffic(t *testing.T) {
 		go func(innerwg *sync.WaitGroup) {
 			defer innerwg.Done()
 			for i := 0; i < 500; i++ {
-				resp, err := http.Post("http://localhost:8286/write?db=mydb", "", bytes.NewBuffer([]byte(testMsgs)))
+				resp, err := http.Post(createURL(listener, "/write", "db=mydb"), "", bytes.NewBuffer([]byte(testMsgs)))
 				require.NoError(t, err)
 				require.EqualValues(t, 204, resp.StatusCode)
 			}
@@ -251,7 +261,7 @@ func TestReceive404ForInvalidEndpoint(t *testing.T) {
 	defer listener.Stop()
 
 	// post single message to listener
-	resp, err := http.Post("http://localhost:8186/foobar", "", bytes.NewBuffer([]byte(testMsg)))
+	resp, err := http.Post(createURL(listener, "/foobar", ""), "", bytes.NewBuffer([]byte(testMsg)))
 	require.NoError(t, err)
 	require.EqualValues(t, 404, resp.StatusCode)
 }
@@ -264,7 +274,7 @@ func TestWriteHTTPInvalid(t *testing.T) {
 	defer listener.Stop()
 
 	// post single message to listener
-	resp, err := http.Post("http://localhost:8186/write?db=mydb", "", bytes.NewBuffer([]byte(badMsg)))
+	resp, err := http.Post(createURL(listener, "/write", "db=mydb"), "", bytes.NewBuffer([]byte(badMsg)))
 	require.NoError(t, err)
 	require.EqualValues(t, 400, resp.StatusCode)
 }
@@ -277,7 +287,7 @@ func TestWriteHTTPEmpty(t *testing.T) {
 	defer listener.Stop()
 
 	// post single message to listener
-	resp, err := http.Post("http://localhost:8186/write?db=mydb", "", bytes.NewBuffer([]byte(emptyMsg)))
+	resp, err := http.Post(createURL(listener, "/write", "db=mydb"), "", bytes.NewBuffer([]byte(emptyMsg)))
 	require.NoError(t, err)
 	require.EqualValues(t, 204, resp.StatusCode)
 }
@@ -290,12 +300,13 @@ func TestQueryAndPingHTTP(t *testing.T) {
 	defer listener.Stop()
 
 	// post query to listener
-	resp, err := http.Post("http://localhost:8186/query?db=&q=CREATE+DATABASE+IF+NOT+EXISTS+%22mydb%22", "", nil)
+	resp, err := http.Post(
+		createURL(listener, "/query", "db=&q=CREATE+DATABASE+IF+NOT+EXISTS+%22mydb%22"), "", nil)
 	require.NoError(t, err)
 	require.EqualValues(t, 200, resp.StatusCode)
 
 	// post ping to listener
-	resp, err = http.Post("http://localhost:8186/ping", "", nil)
+	resp, err = http.Post(createURL(listener, "/ping", ""), "", nil)
 	require.NoError(t, err)
 	require.EqualValues(t, 204, resp.StatusCode)
 }