fix failing tests

Author: NiniOak

agent/http.go

@@ -360,10 +360,12 @@ func ensureContentTypeHeader(next http.Handler, logger hclog.Logger) http.Handle
 		}
 
 		// validate response content-type header
-		respContentType := resp.Header().Get(api.ContentTypeHeader)
-		if respContentType == "" || respContentType != contentType {
-			logger.Debug("warning: response content-type header not explicitly set.", "request-path", req.URL)
-			resp.Header().Set(api.ContentTypeHeader, contentType)
+		if resp != nil {
+			respContentType := resp.Header().Get(api.ContentTypeHeader)
+			if respContentType == "" || respContentType != contentType {
+				logger.Debug("warning: response content-type header not explicitly set.", "request-path", req.URL)
+				resp.Header().Set(api.ContentTypeHeader, contentType)
+			}
 		}
 	})
 }

agent/http_test.go

@@ -617,7 +617,6 @@ func TestHTTPAPI_DefaultACLPolicy(t *testing.T) {
 		})
 	}
 }
-
 func TestHTTPAPIResponseHeaders(t *testing.T) {
 	if testing.Short() {
 		t.Skip("too slow for testing.Short")
@@ -643,7 +642,7 @@ func TestHTTPAPIResponseHeaders(t *testing.T) {
 
 	// Check the Index page that just renders a simple message with UI disabled
 	// also gets the right headers.
-	requireHasHeadersSet(t, a, http.MethodGet, "/", nil, api.JSONContentType)
+	requireHasHeadersSet(t, a, http.MethodGet, "/", nil, api.PlainContentType)
 }
 
 func TestHTTPAPISnapshotEndpointResponseHeaders(t *testing.T) {

api/api.go

@@ -1099,9 +1099,11 @@ func (c *Client) doRequest(r *request) (time.Duration, *http.Response, error) {
 	start := time.Now()
 	resp, err := c.config.HttpClient.Do(req)
 	// validate response content-type header
-	respContentType := resp.Header.Get(ContentTypeHeader)
-	if respContentType == "" || respContentType != contentType {
-		resp.Header.Set(ContentTypeHeader, contentType)
+	if resp != nil {
+		respContentType := resp.Header.Get(ContentTypeHeader)
+		if respContentType == "" || respContentType != contentType {
+			resp.Header.Set(ContentTypeHeader, contentType)
+		}
 	}
 
 	diff := time.Since(start)

api/content_type.go

@@ -61,6 +61,10 @@ func DetermineContentType(req *http.Request) string {
 		return PlainContentType
 	}
 
+	if isIndexPage(req) {
+		return PlainContentType
+	}
+
 	if strings.HasPrefix(req.URL.Path, "/v1/internal") {
 		return req.Header.Get(ContentTypeHeader)
 	}
@@ -81,3 +85,8 @@ func matchesRule(req *http.Request, rule ContentTypeRule) bool {
 	return strings.HasPrefix(req.URL.Path, rule.Path) &&
 		(rule.Method == "" || req.Method == rule.Method)
 }
+
+// isIndexPage checks if the request is for the index page
+func isIndexPage(req *http.Request) bool {
+	return req.URL.Path == "/"
+}