Chore: Use Header.Set method instead of Header.Add (#29804)

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

pkg/api/avatar/avatar.go

@@ -107,13 +107,13 @@ func (a *CacheServer) Handler(ctx *models.ReqContext) {
 		}
 	}
 
-	ctx.Resp.Header().Add("Content-Type", "image/jpeg")
+	ctx.Resp.Header().Set("Content-Type", "image/jpeg")
 
 	if !setting.EnableGzip {
-		ctx.Resp.Header().Add("Content-Length", strconv.Itoa(len(avatar.data.Bytes())))
+		ctx.Resp.Header().Set("Content-Length", strconv.Itoa(len(avatar.data.Bytes())))
 	}
 
-	ctx.Resp.Header().Add("Cache-Control", "private, max-age=3600")
+	ctx.Resp.Header().Set("Cache-Control", "private, max-age=3600")
 
 	if err := avatar.Encode(ctx.Resp); err != nil {
 		log.Warnf("avatar encode error: %v", err)

pkg/api/basic_auth_test.go

@@ -22,7 +22,7 @@ func TestBasicAuthenticatedRequest(t *testing.T) {
 			Request: httpReq,
 		}
 		encodedCreds := encodeBasicAuthCredentials(expectedUser, expectedPass)
-		req.Header.Add("Authorization", fmt.Sprintf("Basic %s", encodedCreds))
+		req.Header.Set("Authorization", fmt.Sprintf("Basic %s", encodedCreds))
 		authenticated := BasicAuthenticatedRequest(req, expectedUser, expectedPass)
 
 		assert.True(t, authenticated)
@@ -35,7 +35,7 @@ func TestBasicAuthenticatedRequest(t *testing.T) {
 			Request: httpReq,
 		}
 		encodedCreds := encodeBasicAuthCredentials("invaliduser", "invalidpass")
-		req.Header.Add("Authorization", fmt.Sprintf("Basic %s", encodedCreds))
+		req.Header.Set("Authorization", fmt.Sprintf("Basic %s", encodedCreds))
 		authenticated := BasicAuthenticatedRequest(req, expectedUser, expectedPass)
 
 		assert.False(t, authenticated)

pkg/api/pluginproxy/access_token_provider.go

@@ -114,8 +114,8 @@ func (provider *accessTokenProvider) getAccessToken(data templateData) (string,
 	}
 
 	getTokenReq, _ := http.NewRequest("POST", urlInterpolated, bytes.NewBufferString(params.Encode()))
-	getTokenReq.Header.Add("Content-Type", "application/x-www-form-urlencoded")
+	getTokenReq.Header.Set("Content-Type", "application/x-www-form-urlencoded")
-	getTokenReq.Header.Add("Content-Length", strconv.Itoa(len(params.Encode())))
+	getTokenReq.Header.Set("Content-Length", strconv.Itoa(len(params.Encode())))
 
 	resp, err := client.Do(getTokenReq)
 	if err != nil {

pkg/api/pluginproxy/ds_proxy_test.go

@@ -390,9 +390,9 @@ func TestDataSourceProxy_routeRule(t *testing.T) {
 		proxy, err := NewDataSourceProxy(ds, plugin, ctx, "/path/to/folder/", &setting.Cfg{})
 		require.NoError(t, err)
 		req, err := http.NewRequest(http.MethodGet, "http://grafana.com/sub", nil)
-		req.Header.Add("Origin", "grafana.com")
+		req.Header.Set("Origin", "grafana.com")
-		req.Header.Add("Referer", "grafana.com")
+		req.Header.Set("Referer", "grafana.com")
-		req.Header.Add("X-Canary", "stillthere")
+		req.Header.Set("X-Canary", "stillthere")
 		require.NoError(t, err)
 
 		proxy.director(req)

pkg/middleware/middleware.go

@@ -51,24 +51,24 @@ func addSecurityHeaders(w macaron.ResponseWriter, cfg *setting.Cfg) {
 		if cfg.StrictTransportSecuritySubDomains {
 			strictHeaderValues = append(strictHeaderValues, "includeSubDomains")
 		}
-		w.Header().Add("Strict-Transport-Security", strings.Join(strictHeaderValues, "; "))
+		w.Header().Set("Strict-Transport-Security", strings.Join(strictHeaderValues, "; "))
 	}
 
 	if cfg.ContentTypeProtectionHeader {
-		w.Header().Add("X-Content-Type-Options", "nosniff")
+		w.Header().Set("X-Content-Type-Options", "nosniff")
 	}
 
 	if cfg.XSSProtectionHeader {
-		w.Header().Add("X-XSS-Protection", "1; mode=block")
+		w.Header().Set("X-XSS-Protection", "1; mode=block")
 	}
 }
 
 func addNoCacheHeaders(w macaron.ResponseWriter) {
-	w.Header().Add("Cache-Control", "no-cache")
+	w.Header().Set("Cache-Control", "no-cache")
-	w.Header().Add("Pragma", "no-cache")
+	w.Header().Set("Pragma", "no-cache")
-	w.Header().Add("Expires", "-1")
+	w.Header().Set("Expires", "-1")
 }
 
 func addXFrameOptionsDenyHeader(w macaron.ResponseWriter) {
-	w.Header().Add("X-Frame-Options", "deny")
+	w.Header().Set("X-Frame-Options", "deny")
 }

pkg/middleware/recovery_test.go

@@ -21,7 +21,7 @@ func TestRecoveryMiddleware(t *testing.T) {
 		recoveryScenario(t, "recovery middleware should return json", apiURL, func(t *testing.T, sc *scenarioContext) {
 			sc.handlerFunc = panicHandler
 			sc.fakeReq("GET", apiURL).exec()
-			sc.req.Header.Add("content-type", "application/json")
+			sc.req.Header.Set("content-type", "application/json")
 
 			assert.Equal(t, 500, sc.resp.Code)
 			assert.Equal(t, "Internal Server Error - Check the Grafana server logs for the detailed error message.", sc.respJson["message"])

pkg/middleware/testing.go

@@ -88,12 +88,12 @@ func (sc *scenarioContext) exec() {
 
 	if sc.apiKey != "" {
 		sc.t.Logf(`Adding header "Authorization: Bearer %s"`, sc.apiKey)
-		sc.req.Header.Add("Authorization", "Bearer "+sc.apiKey)
+		sc.req.Header.Set("Authorization", "Bearer "+sc.apiKey)
 	}
 
 	if sc.authHeader != "" {
 		sc.t.Logf(`Adding header "Authorization: %s"`, sc.authHeader)
-		sc.req.Header.Add("Authorization", sc.authHeader)
+		sc.req.Header.Set("Authorization", sc.authHeader)
 	}
 
 	if sc.tokenSessionCookie != "" {

pkg/plugins/backendplugin/manager.go

@@ -343,6 +343,8 @@ func flushStream(plugin Plugin, stream CallResourceClientResponseStream, w http.
 				}
 
 				for _, v := range values {
+					// TODO: Figure out if we should use Set here instead
+					// nolint:gocritic
 					w.Header().Add(k, v)
 				}
 			}

pkg/services/notifications/webhook.go

@@ -61,11 +61,11 @@ func (ns *NotificationService) sendWebRequestSync(ctx context.Context, webhook *
 		webhook.ContentType = "application/json"
 	}
 
-	request.Header.Add("Content-Type", webhook.ContentType)
+	request.Header.Set("Content-Type", webhook.ContentType)
-	request.Header.Add("User-Agent", "Grafana")
+	request.Header.Set("User-Agent", "Grafana")
 
 	if webhook.User != "" && webhook.Password != "" {
-		request.Header.Add("Authorization", util.GetBasicAuthHeader(webhook.User, webhook.Password))
+		request.Header.Set("Authorization", util.GetBasicAuthHeader(webhook.User, webhook.Password))
 	}
 
 	for k, v := range webhook.HttpHeader {

pkg/tsdb/elasticsearch/client/client_test.go

@@ -407,7 +407,7 @@ func httpClientScenario(t *testing.T, desc string, ds *models.DataSource, fn sce
 
 			sc.requestBody = bytes.NewBuffer(buf)
 
-			rw.Header().Add("Content-Type", "application/json")
+			rw.Header().Set("Content-Type", "application/json")
 			_, err = rw.Write([]byte(sc.responseBody))
 			require.Nil(t, err)
 			rw.WriteHeader(sc.responseStatus)

pkg/util/proxyutil/proxyutil_test.go

@@ -11,9 +11,9 @@ func TestPrepareProxyRequest(t *testing.T) {
 	t.Run("Prepare proxy request should clear X-Forwarded headers", func(t *testing.T) {
 		req, err := http.NewRequest(http.MethodGet, "/", nil)
 		require.NoError(t, err)
-		req.Header.Add("X-Forwarded-Host", "host")
+		req.Header.Set("X-Forwarded-Host", "host")
-		req.Header.Add("X-Forwarded-Port", "123")
+		req.Header.Set("X-Forwarded-Port", "123")
-		req.Header.Add("X-Forwarded-Proto", "http1")
+		req.Header.Set("X-Forwarded-Proto", "http1")
 
 		PrepareProxyRequest(req)
 		require.NotContains(t, req.Header, "X-Forwarded-Host")
@@ -34,7 +34,7 @@ func TestPrepareProxyRequest(t *testing.T) {
 	t.Run("Prepare proxy request should append client ip at the end of X-Forwarded-For", func(t *testing.T) {
 		req, err := http.NewRequest(http.MethodGet, "/", nil)
 		req.RemoteAddr = "127.0.0.1:1234"
-		req.Header.Add("X-Forwarded-For", "192.168.0.1")
+		req.Header.Set("X-Forwarded-For", "192.168.0.1")
 		require.NoError(t, err)
 
 		PrepareProxyRequest(req)