Avoid AssertException for persisted query

Closes gh-930

spring-graphql-docs/modules/ROOT/pages/request-execution.adoc

@@ -308,7 +308,8 @@ In Spring GraphQL you can register a `PreparsedDocumentProvider` through
 GraphQlSource.Builder builder = ...
 
 // Create provider
-PreparsedDocumentProvider provider = ...
+PreparsedDocumentProvider provider =
+        new ApolloPersistedQuerySupport(new InMemoryPersistedQueryCache(Collections.emptyMap()));
 
 builder.schemaResources(..)
 		.configureRuntimeWiring(..)

spring-graphql/src/main/java/org/springframework/graphql/server/support/SerializableGraphQlRequest.java

@@ -17,6 +17,8 @@ package org.springframework.graphql.server.support;
 
 import java.util.Map;
 
+import graphql.execution.preparsed.persisted.PersistedQuerySupport;
+
 import org.springframework.graphql.GraphQlRequest;
 import org.springframework.lang.Nullable;
 import org.springframework.web.server.ServerWebInputException;
@@ -85,6 +87,9 @@ public class SerializableGraphQlRequest implements GraphQlRequest {
 	@Override
 	public String getDocument() {
 		if (this.query == null) {
+			if (this.extensions != null && this.extensions.get("persistedQuery") != null) {
+				return PersistedQuerySupport.PERSISTED_QUERY_MARKER;
+			}
 			throw new ServerWebInputException("No 'query'");
 		}
 		return this.query;

spring-graphql/src/test/java/org/springframework/graphql/server/webmvc/GraphQlHttpHandlerTests.java

@@ -22,10 +22,11 @@ import java.util.List;
 import java.util.Locale;
 import java.util.UUID;
 
-import jakarta.servlet.ServletException;
-
 import com.jayway.jsonpath.DocumentContext;
 import com.jayway.jsonpath.JsonPath;
+import graphql.execution.preparsed.persisted.ApolloPersistedQuerySupport;
+import graphql.execution.preparsed.persisted.InMemoryPersistedQueryCache;
+import jakarta.servlet.ServletException;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.context.i18n.LocaleContextHolder;
@@ -109,6 +110,45 @@ public class GraphQlHttpHandlerTests {
 		assertThatNoException().isThrownBy(() -> UUID.fromString(id));
 	}
 
+	@Test
+	void persistedQuery() throws Exception {
+
+		ApolloPersistedQuerySupport documentProvider =
+				new ApolloPersistedQuerySupport(new InMemoryPersistedQueryCache(Collections.emptyMap()));
+
+		GraphQlHttpHandler handler = GraphQlSetup.schemaContent("type Query { greeting: String }")
+				.configureGraphQl(builder -> builder.preparsedDocumentProvider(documentProvider))
+				.toHttpHandler();
+
+		String document = """
+			{
+				"query" : "{__typename}",
+				"extensions": {
+					"persistedQuery": {
+						"version":1,
+						"sha256Hash":"ecf4edb46db40b5132295c0291d62fb65d6759a9eedfa4d5d612dd5ec54a6b38"
+					}
+				}
+			}""";
+
+		MockHttpServletResponse servletResponse = handleRequest(createServletRequest(document, "*/*"), handler);
+		assertThat(servletResponse.getContentAsString()).isEqualTo("{\"data\":{\"__typename\":\"Query\"}}");
+
+		document = """
+			{
+				"extensions":{
+					"persistedQuery":{
+						"version":1,
+						"sha256Hash":"ecf4edb46db40b5132295c0291d62fb65d6759a9eedfa4d5d612dd5ec54a6b38"
+					}
+				}
+			}""";
+
+		servletResponse = handleRequest(createServletRequest(document, "*/*"), handler);
+		assertThat(servletResponse.getContentAsString()).isEqualTo("{\"data\":{\"__typename\":\"Query\"}}");
+	}
+
+
 	private MockHttpServletRequest createServletRequest(String query, String accept) {
 		MockHttpServletRequest servletRequest = new MockHttpServletRequest("POST", "/");
 		servletRequest.setContentType(MediaType.APPLICATION_JSON_VALUE);

spring-graphql/src/testFixtures/java/org/springframework/graphql/GraphQlSetup.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,6 +19,7 @@ import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
+import java.util.function.Consumer;
 
 import graphql.GraphQL;
 import graphql.execution.instrumentation.Instrumentation;
@@ -137,6 +138,11 @@ public class GraphQlSetup implements GraphQlServiceSetup {
 		return this;
 	}
 
+	public GraphQlSetup configureGraphQl(Consumer<GraphQL.Builder> configurer) {
+		this.graphQlSourceBuilder.configureGraphQl(configurer);
+		return this;
+	}
+
 	public GraphQL toGraphQl() {
 		return this.graphQlSourceBuilder.build().graphQl();
 	}