JsonMappingException: No serializer found for class graphql.execution.TypeInfo

[zash80]

The following exception is thrown writing GraphQL execution result with errors to response:

com.fasterxml.jackson.databind.JsonMappingException: No serializer found for class graphql.execution.TypeInfo and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: java.util.HashMap["errors"]->java.util.ArrayList[0]->graphql.execution.NonNullableFieldWasNullException["typeInfo"])
	at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:284) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.SerializerProvider.mappingException(SerializerProvider.java:1110) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.SerializerProvider.reportMappingProblem(SerializerProvider.java:1135) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.impl.UnknownSerializer.failForEmpty(UnknownSerializer.java:69) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.impl.UnknownSerializer.serialize(UnknownSerializer.java:32) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:704) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:690) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:155) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.impl.IndexedListSerializer.serializeContents(IndexedListSerializer.java:119) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.impl.IndexedListSerializer.serialize(IndexedListSerializer.java:79) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.impl.IndexedListSerializer.serialize(IndexedListSerializer.java:18) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.std.MapSerializer.serializeFields(MapSerializer.java:633) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.std.MapSerializer.serialize(MapSerializer.java:536) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.std.MapSerializer.serialize(MapSerializer.java:30) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:292) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ObjectMapper._configAndWriteValue(ObjectMapper.java:3681) ~[jackson-databind-2.8.8.jar:2.8.8]
	at com.fasterxml.jackson.databind.ObjectMapper.writeValueAsString(ObjectMapper.java:3057) ~[jackson-databind-2.8.8.jar:2.8.8]
	at graphql.servlet.GraphQLServlet.query(GraphQLServlet.java:281) [graphql-java-servlet-4.1.0.jar:na]
	at graphql.servlet.GraphQLServlet.query(GraphQLServlet.java:264) [graphql-java-servlet-4.1.0.jar:na]
	at graphql.servlet.GraphQLServlet.lambda$new$1(GraphQLServlet.java:185) [graphql-java-servlet-4.1.0.jar:na]
	at graphql.servlet.GraphQLServlet.doRequest(GraphQLServlet.java:222) [graphql-java-servlet-4.1.0.jar:na]
	at graphql.servlet.GraphQLServlet.doPost(GraphQLServlet.java:240) [graphql-java-servlet-4.1.0.jar:na]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:707) [javax.servlet-api-3.1.0.jar:3.1.0]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) [javax.servlet-api-3.1.0.jar:3.1.0]
`


Here a NonNullableFieldWasNullException containing a TypeInfo field is going to be serialized without matching Jackson Serializer.

[luoruici]

+1

[apottere]

I'll take a look

[apottere]

It looks like this is because in graphql-java 3.0.0, the getters in TypeInfo don't start with "get", they're just the names of the field: https://github.com/graphql-java/graphql-java/blob/v3.0.0/src/main/java/graphql/execution/TypeInfo.java

The class was renamed to ExecutionTypeInfo and the getters are fixed on the current master: https://github.com/graphql-java/graphql-java/blob/master/src/main/java/graphql/execution/ExecutionTypeInfo.java

I'll provide a custom serializer for now, but it should be fixed in 4.0.0 and I'll remove the custom serializer then.