Hello,
we are using the JSON layout in our Spring Boot application to easily ingest
the logs in Elasticsearch.
One message that we log is about failed conversions, when an incoming request
parameter cannot be converted correctly. As we use Spring’s Converter
functionality for this, these `IllegalArgumentException`s are wrapped in a
`ConversionFailedException`. This exception has fields of type `TypeDescriptor`
which hold information about the source and the target type of the conversion.
The problem is, that these `TypeDescriptor` objects cannot be serialized to
JSON. The simple call
com.fasterxml.jackson.databind.ObjectMapper().writeValueAsString(org.springframework.core.convert.TypeDescriptor.valueOf(String.javaClass))
throws an exception like
ERROR StatusLogger
com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Direct
self-reference leading to cycle (through reference chain:
org.springframework.core.ResolvableType["componentType"]->org.springframework.core.ResolvableType["componentType"])
com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Direct
self-reference leading to cycle (through reference chain:
org.springframework.core.ResolvableType["componentType"]->org.springframework.core.ResolvableType["componentType"])
at
com.fasterxml.jackson.databind.exc.InvalidDefinitionException.from(InvalidDefinitionException.java:77)
at
com.fasterxml.jackson.databind.SerializerProvider.reportBadDefinition(SerializerProvider.java:1191)
at
com.fasterxml.jackson.databind.ser.BeanPropertyWriter._handleSelfReference(BeanPropertyWriter.java:944)
at
com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:721)
at
com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:719)
at
com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:155)
The error can be prevented if `Mixin`s are added to the `ObjectMapper` which
ignore the corresponding class.
The `Log4jJsonObjectMapper` is initialized in the `JacksonFactory.JSON` class
and I currently do not see any way to somehow configure this ObjectMapper with
additional MixIns.
Hence, my question finally is:
How can I configure Log4J’s JSON mapping to not break on such non-serializable
log content?
Thank you!
Dominik
