diff --git a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/autoconfigure/MvcAutoConfiguration.java b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/autoconfigure/MvcAutoConfiguration.java
index 0ebba5f..b3de175 100644
--- a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/autoconfigure/MvcAutoConfiguration.java
+++ b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/autoconfigure/MvcAutoConfiguration.java
@@ -1,5 +1,6 @@
 package io.leangen.graphql.spqr.spring.autoconfigure;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
 import graphql.GraphQL;
 import graphql.schema.GraphQLSchema;
 import io.leangen.graphql.spqr.spring.web.GraphQLController;
@@ -43,8 +44,8 @@ public GraphQLMvcExecutor defaultExecutor(MvcContextFactory contextFactory, Spqr
     @ConditionalOnProperty(name = "graphql.spqr.http.enabled", havingValue = "true", matchIfMissing = true)
     @ConditionalOnMissingBean(GraphQLController.class)
     @ConditionalOnBean(GraphQLSchema.class)
-    public DefaultGraphQLController graphQLController(GraphQL graphQL, GraphQLMvcExecutor executor) {
-        return new DefaultGraphQLController(graphQL, executor);
+    public DefaultGraphQLController graphQLController(GraphQL graphQL, GraphQLMvcExecutor executor, ObjectMapper objectMapper) {
+        return new DefaultGraphQLController(graphQL, executor, objectMapper);
     }
 
     @Bean
diff --git a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/autoconfigure/ReactiveAutoConfiguration.java b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/autoconfigure/ReactiveAutoConfiguration.java
index 1732afe..0bf0149 100644
--- a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/autoconfigure/ReactiveAutoConfiguration.java
+++ b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/autoconfigure/ReactiveAutoConfiguration.java
@@ -1,5 +1,6 @@
 package io.leangen.graphql.spqr.spring.autoconfigure;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
 import graphql.GraphQL;
 import graphql.schema.GraphQLSchema;
 import io.leangen.graphql.module.Module;
@@ -47,8 +48,8 @@ public GraphQLReactiveExecutor graphQLExecutor(ReactiveContextFactory contextFac
     @ConditionalOnProperty(name = "graphql.spqr.http.enabled", havingValue = "true", matchIfMissing = true)
     @ConditionalOnMissingBean(GraphQLController.class)
     @ConditionalOnBean(GraphQLSchema.class)
-    public DefaultGraphQLController graphQLController(GraphQL graphQL, GraphQLReactiveExecutor executor) {
-        return new DefaultGraphQLController(graphQL, executor);
+    public DefaultGraphQLController graphQLController(GraphQL graphQL, GraphQLReactiveExecutor executor, ObjectMapper objectMapper) {
+        return new DefaultGraphQLController(graphQL, executor,objectMapper);
     }
 
     @Bean
diff --git a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/GraphQLController.java b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/GraphQLController.java
index 5e5d6e1..eaebce5 100644
--- a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/GraphQLController.java
+++ b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/GraphQLController.java
@@ -1,30 +1,36 @@
 package io.leangen.graphql.spqr.spring.web;
 
-import graphql.GraphQL;
-import io.leangen.graphql.spqr.spring.web.dto.ExecutorParams;
-import io.leangen.graphql.spqr.spring.web.dto.GraphQLRequest;
-import io.leangen.graphql.spqr.spring.web.dto.TransportType;
-import io.leangen.graphql.util.Utils;
+import java.io.IOException;
+import java.util.Collections;
+import java.util.Map;
+
 import org.springframework.http.MediaType;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
-import org.springframework.web.bind.annotation.RequestMapping;
-import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
 
-import java.util.Map;
+import com.fasterxml.jackson.core.type.TypeReference;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+import graphql.GraphQL;
+import io.leangen.graphql.spqr.spring.web.dto.ExecutorParams;
+import io.leangen.graphql.spqr.spring.web.dto.GraphQLRequest;
+import io.leangen.graphql.spqr.spring.web.dto.TransportType;
+import io.leangen.graphql.util.Utils;
 
 @RestController
 public abstract class GraphQLController<R> {
 
     protected final GraphQL graphQL;
     protected final GraphQLExecutor<R> executor;
+    protected final ObjectMapper objectMapper;
 
-    public GraphQLController(GraphQL graphQL, GraphQLExecutor<R> executor) {
+    public GraphQLController(GraphQL graphQL, GraphQLExecutor<R> executor, final ObjectMapper objectMapper) {
         this.graphQL = graphQL;
         this.executor = executor;
+        this.objectMapper = objectMapper;
     }
 
     @PostMapping(
@@ -53,7 +59,8 @@ public Object jsonPost(GraphQLRequest requestBody, GraphQLRequest requestParams,
         String query = Utils.isNotEmpty(requestParams.getQuery()) ? requestParams.getQuery() : requestBody.getQuery();
         String operationName = Utils.isNotEmpty(requestParams.getOperationName()) ? requestParams.getOperationName() : requestBody.getOperationName();
         Map<String, Object> variables = requestParams.getVariables().isEmpty() ? requestBody.getVariables() : requestParams.getVariables();
-        ExecutorParams<R> params = new ExecutorParams<>(new GraphQLRequest(id, query, operationName, variables), request, transportType);
+        Map<String, Object> extensions = requestParams.getExtensions().isEmpty() ? requestBody.getExtensions() : requestParams.getExtensions();
+        ExecutorParams<R> params = new ExecutorParams<>(new GraphQLRequest(id, query, operationName, variables, extensions), request, transportType);
         return executor.execute(graphQL, params);
     }
 
@@ -66,13 +73,12 @@ public Object executeGraphQLPost(@RequestBody String queryBody,
                                    GraphQLRequest originalReq,
                                    R request) {
         String query = Utils.isNotEmpty(originalReq.getQuery()) ? originalReq.getQuery() : queryBody;
-        GraphQLRequest remappedReq = new GraphQLRequest(originalReq.getId(), query, originalReq.getOperationName(), originalReq.getVariables());
+        GraphQLRequest remappedReq = new GraphQLRequest(originalReq.getId(), query, originalReq.getOperationName(), originalReq.getVariables(), originalReq.getExtensions());
         ExecutorParams<R> params = new ExecutorParams<>(remappedReq, request, TransportType.HTTP);
         return executor.execute(graphQL, params);
     }
 
-    @RequestMapping(
-            method = RequestMethod.POST,
+    @PostMapping(
             value = "${graphql.spqr.http.endpoint:/graphql}",
             consumes = {MediaType.APPLICATION_FORM_URLENCODED_VALUE, "application/x-www-form-urlencoded;charset=UTF-8"},
             produces = MediaType.APPLICATION_JSON_VALUE
@@ -88,7 +94,7 @@ public Object executeFormPost(@RequestParam Map<String, String> queryParams,
         String id = Utils.isNotEmpty(idParam) ? idParam : graphQLRequest.getId();
         String query = Utils.isNotEmpty(queryParam) ? queryParam : graphQLRequest.getQuery();
         String operationName = Utils.isEmpty(operationNameParam) ? graphQLRequest.getOperationName() : operationNameParam;
-        ExecutorParams<R> params = new ExecutorParams<>(new GraphQLRequest(id, query, operationName, graphQLRequest.getVariables()), request, TransportType.HTTP);
+        ExecutorParams<R> params = new ExecutorParams<>(new GraphQLRequest(id, query, operationName, graphQLRequest.getVariables(), graphQLRequest.getExtensions()), request, TransportType.HTTP);
 
         return executor.execute(graphQL, params);
     }
@@ -98,8 +104,17 @@ public Object executeFormPost(@RequestParam Map<String, String> queryParams,
             produces = MediaType.APPLICATION_JSON_VALUE,
             headers = { "Connection!=Upgrade", "Connection!=keep-alive, Upgrade" }
     )
-    public Object executeGet(GraphQLRequest graphQLRequest, R request) {
-        return get(graphQLRequest, request, TransportType.HTTP);
+    public Object executeGet(String id,
+                             String query,
+                             String operationName,
+                             String variables,
+                             String extensions,
+                             R request) {
+        return get(new GraphQLRequest(id, query, operationName, parseAsMap(variables), parseAsMap(extensions)), request, TransportType.HTTP);
+    }
+
+    private Object get(GraphQLRequest graphQLRequest, R request, TransportType transportType) {
+        return executor.execute(graphQL, new ExecutorParams<>(graphQLRequest, request, transportType));
     }
 
     @GetMapping(
@@ -107,11 +122,23 @@ public Object executeGet(GraphQLRequest graphQLRequest, R request) {
             produces = MediaType.TEXT_EVENT_STREAM_VALUE,
             headers = { "Connection!=Upgrade", "Connection!=keep-alive, Upgrade" }
     )
-    public Object executeGetEventStream(GraphQLRequest graphQLRequest, R request) {
-        return get(graphQLRequest, request, TransportType.HTTP_EVENT_STREAM);
+    public Object executeGetEventStream(String id,
+                                        String query,
+                                        String operationName,
+                                        String variables,
+                                        String extensions,
+                                        R request) {
+        return get(new GraphQLRequest(id, query, operationName, parseAsMap(variables), parseAsMap(extensions)), request, TransportType.HTTP_EVENT_STREAM);
     }
 
-    private Object get(GraphQLRequest graphQLRequest, R request, TransportType transportType) {
-        return executor.execute(graphQL, new ExecutorParams<>(graphQLRequest, request, transportType));
+    private Map<String, Object> parseAsMap(String str) {
+        if (Utils.isEmpty(str)) {
+            return Collections.emptyMap();
+        }
+        try {
+            return objectMapper.readValue(str, new TypeReference<Map<String, Object>>() {});
+        } catch (IOException e) {
+            throw new IllegalArgumentException("failed to parse: " + str);
+        }
     }
 }
diff --git a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/dto/GraphQLRequest.java b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/dto/GraphQLRequest.java
index abaed52..d3b2e57 100644
--- a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/dto/GraphQLRequest.java
+++ b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/dto/GraphQLRequest.java
@@ -14,16 +14,19 @@ public class GraphQLRequest {
     private final String query;
     private final String operationName;
     private final Map<String, Object> variables;
+    private final Map<String, Object> extensions;
 
-    @JsonCreator
+    @JsonCreator(mode = JsonCreator.Mode.PROPERTIES)
     public GraphQLRequest(@JsonProperty("id") String id,
                           @JsonProperty("query") String query,
                           @JsonProperty("operationName") String operationName,
-                          @JsonProperty("variables") Map<String, Object> variables) {
+                          @JsonProperty("variables") Map<String, Object> variables,
+                          @JsonProperty("extensions") Map<String, Object> extensions) {
         this.id = id;
-        this.query = query;
+        this.query = query == null && extensions != null ? "" : query;
         this.operationName = operationName;
         this.variables = variables != null ? variables : Collections.emptyMap();
+        this.extensions = extensions != null ? extensions : Collections.emptyMap();
     }
 
     public String getId() {
@@ -41,4 +44,7 @@ public String getOperationName() {
     public Map<String, Object> getVariables() {
         return variables;
     }
+
+    public Map<String, Object> getExtensions() { return extensions; }
+
 }
diff --git a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/mvc/DefaultGraphQLController.java b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/mvc/DefaultGraphQLController.java
index 68053e8..47d3af8 100644
--- a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/mvc/DefaultGraphQLController.java
+++ b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/mvc/DefaultGraphQLController.java
@@ -1,5 +1,6 @@
 package io.leangen.graphql.spqr.spring.web.mvc;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
 import graphql.GraphQL;
 import io.leangen.graphql.spqr.spring.web.GraphQLController;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -12,7 +13,7 @@
 public class DefaultGraphQLController extends GraphQLController<NativeWebRequest> {
 
     @Autowired
-    public DefaultGraphQLController(GraphQL graphQL, GraphQLMvcExecutor executor) {
-        super(graphQL, executor);
+    public DefaultGraphQLController(GraphQL graphQL, GraphQLMvcExecutor executor,  ObjectMapper objectMapper) {
+        super(graphQL, executor, objectMapper);
     }
 }
diff --git a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/reactive/DefaultGraphQLController.java b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/reactive/DefaultGraphQLController.java
index e6b2f30..da9ecad 100644
--- a/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/reactive/DefaultGraphQLController.java
+++ b/graphql-spqr-spring-boot-autoconfigure/src/main/java/io/leangen/graphql/spqr/spring/web/reactive/DefaultGraphQLController.java
@@ -1,5 +1,6 @@
 package io.leangen.graphql.spqr.spring.web.reactive;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
 import graphql.GraphQL;
 import io.leangen.graphql.spqr.spring.web.GraphQLController;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -12,7 +13,7 @@
 public class DefaultGraphQLController extends GraphQLController<ServerWebExchange> {
 
     @Autowired
-    public DefaultGraphQLController(GraphQL graphQL, GraphQLReactiveExecutor executor) {
-        super(graphQL, executor);
+    public DefaultGraphQLController(GraphQL graphQL, GraphQLReactiveExecutor executor, ObjectMapper objectMapper) {
+        super(graphQL, executor, objectMapper);
     }
 }
diff --git a/graphql-spqr-spring-boot-autoconfigure/src/test/java/io/leangen/graphql/spqr/spring/web/GraphQLControllerTest.java b/graphql-spqr-spring-boot-autoconfigure/src/test/java/io/leangen/graphql/spqr/spring/web/GraphQLControllerTest.java
index 3c26c17..2d8cd7a 100644
--- a/graphql-spqr-spring-boot-autoconfigure/src/test/java/io/leangen/graphql/spqr/spring/web/GraphQLControllerTest.java
+++ b/graphql-spqr-spring-boot-autoconfigure/src/test/java/io/leangen/graphql/spqr/spring/web/GraphQLControllerTest.java
@@ -1,9 +1,15 @@
 package io.leangen.graphql.spqr.spring.web;
 
-import io.leangen.graphql.spqr.spring.autoconfigure.BaseAutoConfiguration;
-import io.leangen.graphql.spqr.spring.autoconfigure.MvcAutoConfiguration;
-import io.leangen.graphql.spqr.spring.autoconfigure.SpringDataAutoConfiguration;
-import io.leangen.graphql.spqr.spring.test.ResolverBuilder_TestConfig;
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.equalToCompressingWhiteSpace;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
+
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -15,15 +21,10 @@
 import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.web.servlet.MockMvc;
 
-import java.net.URLEncoder;
-import java.nio.charset.StandardCharsets;
-
-import static org.hamcrest.Matchers.containsString;
-import static org.hamcrest.Matchers.equalToCompressingWhiteSpace;
-import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
-import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+import io.leangen.graphql.spqr.spring.autoconfigure.BaseAutoConfiguration;
+import io.leangen.graphql.spqr.spring.autoconfigure.MvcAutoConfiguration;
+import io.leangen.graphql.spqr.spring.autoconfigure.SpringDataAutoConfiguration;
+import io.leangen.graphql.spqr.spring.test.ResolverBuilder_TestConfig;
 
 @RunWith(SpringRunner.class)
 @WebMvcTest
@@ -48,12 +49,22 @@ public void defaultControllerTest_POST_applicationGraphql_noQueryParams() throws
                 .andExpect(content().string(containsString("Hello world")));
     }
 
+    @Test
+    public void defaultControllerTest_POST_applicationJson_persistedQuery() throws Exception {
+        mockMvc.perform(
+                post("/"+apiContext)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"variables\":null,\"operationName\":null,\"extensions\":{\"persistedQuery\":{\"version\":1,\"sha256Hash\":\"fcf31818e50ac3e818ca4bdbc433d6ab73176f0b9d5f9d5ad17e200cdab6fba4\"}}}"))
+                .andExpect(status().isOk())
+                .andExpect(content().string(containsString("Invalid Syntax : offending token '<EOF>' at line 1 column 1")));
+    }
+
     @Test
     public void defaultControllerTest_POST_applicationJson_noQueryParams() throws Exception {
         mockMvc.perform(
                 post("/"+apiContext)
                         .contentType(MediaType.APPLICATION_JSON)
-                        .content("{\"query\":\"{greetingFromBeanSource_wiredAsComponent_byAnnotation}\",\"variables\":null,\"operationName\":null}"))
+                        .content("{\"query\":\"{greetingFromBeanSource_wiredAsComponent_byAnnotation}\",\"variables\":null,\"operationName\":null,\"extensions\":null}"))
                 .andExpect(status().isOk())
                 .andExpect(content().string(containsString("Hello world")));
     }
@@ -77,6 +88,15 @@ public void defaultControllerTest_GET() throws Exception {
                 .andExpect(content().string(containsString("Hello world")));
     }
 
+    @Test
+    public void defaultControllerTest_GET_persistedQuery() throws Exception {
+        mockMvc.perform(
+                get("/"+apiContext)
+                        .param("extensions", "{\"persistedQuery\":{\"version\":1,\"sha256Hash\":\"4b758938f2d00323147290e3b0d041e6a0952e2c694ab2c0ea7212ca08f337b3\"}}"))
+                .andExpect(status().isOk())
+                .andExpect(content().string(containsString("Invalid Syntax : offending token '<EOF>' at line 1 column 1")));
+    }
+
     @Test
     public void defaultControllerTest_POST_applicationGraphql_INVALID() throws Exception {
         mockMvc.perform(
@@ -103,7 +123,7 @@ public void defaultControllerTest_POST_applicationJson_INVALID() throws Exceptio
         mockMvc.perform(
                 post("/"+apiContext)
                         .contentType(MediaType.APPLICATION_JSON)
-                        .content("{\"query\":\"{INVALID_QUERY}\",\"variables\":null,\"operationName\":null}"))
+                        .content("{\"query\":\"{INVALID_QUERY}\",\"variables\":null,\"operationName\":null,\"extensions\":null}"))
                 .andExpect(status().isOk())
                 .andExpect(content().string(containsString("FieldUndefined: Field 'INVALID_QUERY'")));
     }
@@ -114,7 +134,7 @@ public void defaultControllerTest_POST_applicationJson_overridingQueryParams() t
                 post("/"+apiContext)
                         .param("query","{greetingFromBeanSource_wiredAsComponent_byAnnotation}")
                         .contentType(MediaType.APPLICATION_JSON)
-                        .content("{\"query\":\"{INVALID_QUERY}\",\"variables\":null,\"operationName\":null}"))
+                        .content("{\"query\":\"{INVALID_QUERY}\",\"variables\":null,\"operationName\":null,\"extensions\":null}"))
                 .andExpect(status().isOk())
                 .andExpect(content().string(containsString("Hello world")));
     }
diff --git a/graphql-spqr-spring-boot-autoconfigure/src/test/java/io/leangen/graphql/spqr/spring/web/reactive/GraphQLReactiveControllerTest.java b/graphql-spqr-spring-boot-autoconfigure/src/test/java/io/leangen/graphql/spqr/spring/web/reactive/GraphQLReactiveControllerTest.java
index 5369c75..cae311b 100644
--- a/graphql-spqr-spring-boot-autoconfigure/src/test/java/io/leangen/graphql/spqr/spring/web/reactive/GraphQLReactiveControllerTest.java
+++ b/graphql-spqr-spring-boot-autoconfigure/src/test/java/io/leangen/graphql/spqr/spring/web/reactive/GraphQLReactiveControllerTest.java
@@ -19,6 +19,7 @@
 import org.springframework.web.reactive.function.BodyInserters;
 
 import java.net.URI;
+import java.util.Map;
 
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -44,6 +45,34 @@ public void setUp() {
         webTestClient = WebTestClient.bindToApplicationContext(context).build();
     }
 
+    @Test
+    public void defaultControllerTest_GET_mono() {
+        webTestClient.get()
+                .uri(uriBuilder -> uriBuilder
+                        .path("/" + apiContext)
+                        .queryParam("query", "{query}")
+                        .build("{greetingFromAnnotatedSourceReactive_mono}"))
+                .accept(MediaType.TEXT_EVENT_STREAM)
+                .exchange()
+                .expectStatus().isOk()
+                .expectBody(String.class)
+                .consumeWith(c -> assertThat("", c.getResponseBody(), containsString("Hello world !")));
+    }
+
+    @Test
+    public void defaultControllerTest_GET_persistedQuery_mono() {
+        webTestClient.get()
+                .uri(uriBuilder -> uriBuilder
+                        .path("/" + apiContext)
+                        .queryParam("extensions", "{persisted}")
+                        .build("{\"persistedQuery\":{\"version\":1,\"sha256Hash\":\"4b758938f2d00323147290e3b0d041e6a0952e2c694ab2c0ea7212ca08f337b3\"}}"))
+                .accept(MediaType.TEXT_EVENT_STREAM)
+                .exchange()
+                .expectStatus().isOk()
+                .expectBody(String.class)
+                .consumeWith(c -> assertThat("", c.getResponseBody(), containsString("Invalid Syntax : offending token '<EOF>' at line 1 column 1\"")));
+    }
+
     @Test
     public void defaultControllerTest_POST_formUrlEncoded_mono() {
         LinkedMultiValueMap<String, String> body = new LinkedMultiValueMap<>();