clients.go: change implementation to send Host header correctly

Turns out there is a way to send Host header correctly with fasthttp.
This commit also adds a bunch of tests to improve coverage.

Updates #41.

args_parser_test.go

@@ -50,6 +50,41 @@ func TestArgsParsing(t *testing.T) {
 		in  [][]string
 		out config
 	}{
+		{
+			[][]string{
+				{programName, ":8080"},
+				{programName, "localhost:8080"},
+			},
+			config{
+				numConns:      defaultNumberOfConns,
+				timeout:       defaultTimeout,
+				headers:       new(headersList),
+				method:        "GET",
+				url:           "http://localhost:8080",
+				printIntro:    true,
+				printProgress: true,
+				printResult:   true,
+				format:        knownFormat("plain-text"),
+			},
+		},
+		{
+			[][]string{
+				{programName, "https://"},
+				{programName, "https://:443"},
+				{programName, "https://localhost"},
+			},
+			config{
+				numConns:      defaultNumberOfConns,
+				timeout:       defaultTimeout,
+				headers:       new(headersList),
+				method:        "GET",
+				url:           "https://localhost:443",
+				printIntro:    true,
+				printProgress: true,
+				printResult:   true,
+				format:        knownFormat("plain-text"),
+			},
+		},
 		{
 			[][]string{{programName, "https://somehost.somedomain"}},
 			config{
@@ -790,3 +825,18 @@ func TestArgsParsingWithInvalidPrintSpec(t *testing.T) {
 		}
 	}
 }
+
+func TestTryParseUrl(t *testing.T) {
+	invalid := []string{
+		"ftp://bla:89",
+		"http://bla:bla:bla",
+		"htp:/bla:bla:bla",
+	}
+
+	for _, url := range invalid {
+		_, err := tryParseURL(url)
+		if err == nil {
+			t.Errorf("%q is not a valid URL", url)
+		}
+	}
+}

bombardier_test.go

@@ -703,3 +703,41 @@ func testBombardierStreamsBodyFromFile(clientType clientTyp, t *testing.T) {
 	b.disableOutput()
 	b.bombard()
 }
+
+func TestBombardierShouldSendCustomHostHeader(t *testing.T) {
+	testAllClients(t, testBombardierShouldSendCustomHostHeader)
+}
+
+func testBombardierShouldSendCustomHostHeader(
+	clientType clientTyp, t *testing.T,
+) {
+	host := "custom-host"
+	s := httptest.NewServer(
+		http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+			if r.Host != host {
+				t.Errorf("Host must be %q, but it's %q", host, r.Host)
+			}
+		}),
+	)
+	defer s.Close()
+	numReqs := uint64(100)
+	headers := headersList([]header{
+		{"Host", host},
+	})
+	b, e := newBombardier(config{
+		numConns:   defaultNumberOfConns,
+		numReqs:    &numReqs,
+		url:        s.URL,
+		headers:    &headers,
+		timeout:    defaultTimeout,
+		method:     "GET",
+		body:       "",
+		clientType: clientType,
+		format:     knownFormat("plain-text"),
+	})
+	if e != nil {
+		t.Error(e)
+	}
+	b.disableOutput()
+	b.bombard()
+}

clients.go

@@ -36,19 +36,28 @@ type clientOpts struct {
 }
 
 type fasthttpClient struct {
-	client *fasthttp.Client
+	client *fasthttp.HostClient
 
-	headers     *fasthttp.RequestHeader
-	url, method string
+	headers                  *fasthttp.RequestHeader
+	host, requestURI, method string
 
 	body    *string
 	bodProd bodyStreamProducer
 }
 
 func newFastHTTPClient(opts *clientOpts) client {
 	c := new(fasthttpClient)
-	c.client = &fasthttp.Client{
-		MaxConnsPerHost:               int(opts.maxConns),
+	u, err := url.Parse(opts.url)
+	if err != nil {
+		// opts.url guaranteed to be valid at this point
+		panic(err)
+	}
+	c.host = u.Host
+	c.requestURI = "/" + u.Path + "?" + u.RawQuery
+	c.client = &fasthttp.HostClient{
+		Addr:                          u.Host,
+		IsTLS:                         u.Scheme == "https",
+		MaxConns:                      int(opts.maxConns),
 		ReadTimeout:                   opts.timeout,
 		WriteTimeout:                  opts.timeout,
 		DisableHeaderNamesNormalizing: true,
@@ -58,7 +67,7 @@ func newFastHTTPClient(opts *clientOpts) client {
 		),
 	}
 	c.headers = headersToFastHTTPHeaders(opts.headers)
-	c.url, c.method, c.body = opts.url, opts.method, opts.body
+	c.method, c.body = opts.method, opts.body
 	c.bodProd = opts.bodProd
 	return client(c)
 }
@@ -72,8 +81,11 @@ func (c *fasthttpClient) do() (
 	if c.headers != nil {
 		c.headers.CopyTo(&req.Header)
 	}
+	if len(req.Header.Host()) == 0 {
+		req.Header.SetHost(c.host)
+	}
 	req.Header.SetMethod(c.method)
-	req.SetRequestURI(c.url)
+	req.SetRequestURI(c.requestURI)
 	if c.body != nil {
 		req.SetBodyString(*c.body)
 	} else {