JSON Rules

Rules for controlling how types are serialized to JSON in the documentation.

Available Rules

Rule Key	Type	Description
json.rule.convert	string	Convert one type to another
json.additional.field	string (merge)	Add extra fields to JSON output
json.unwrapped	boolean	Unwrap nested objects (like @JsonUnwrapped)
field.max.depth	int	Maximum depth for field expansion
param.max.depth	int	Maximum depth for parameter expansion

JSON Lifecycle Events

Rule Key	Type	Description
json.class.parse.before	event	Before parsing a class as JSON
json.class.parse.after	event	After parsing a class as JSON
json.field.parse.before	event (alias: field.parse.before)	Before parsing a field as JSON
json.field.parse.after	event (alias: field.parse.after)	After parsing a field as JSON

json.rule.convert

Convert complex or generic types to simpler representations:

###set resolveProperty = false
json.rule.convert[#regex:org.springframework.http.HttpEntity]=java.lang.Object
json.rule.convert[#regex:org.springframework.http.HttpEntity<(.*?)>]=${1}
json.rule.convert[#regex:org.springframework.http.RequestEntity<(.*?)>]=${1}
json.rule.convert[#regex:org.springframework.http.RequestEntity]=java.lang.Object
json.rule.convert[#regex:org.springframework.http.ResponseEntity<(.*?)>]=${1}
json.rule.convert[#regex:org.springframework.http.ResponseEntity]=java.lang.Object

json.rule.convert[#regex:reactor.core.publisher.Mono<(.*?)>]=${1}
json.rule.convert[#regex:reactor.core.publisher.Flux<(.*?)>]=java.util.List<${1}>
###set resolveProperty = true

Custom Type Conversion

json.rule.convert[#regex:com.example.Result<(.*?)>]=${1}
json.rule.convert[#regex:com.example.PageResult<(.*?)>]=java.util.List<${1}>

json.rule.convert[#regex:java.time.LocalDate]=java.lang.String
json.rule.convert[#regex:java.time.LocalDateTime]=java.lang.String
json.rule.convert[#regex:java.math.BigDecimal]=java.lang.Number

json.additional.field

Add extra fields to the JSON output of a class. This is useful for adding metadata or computed fields:

json.additional.field=groovy:{"name":"_type","value":"User","desc":"Object type","required":false}

Multiple additional fields can be added (merge mode):

json.additional.field=groovy:{"name":"_type","value":it.name(),"desc":"Object type","required":false}
json.additional.field=groovy:{"name":"_timestamp","value":"0","desc":"Timestamp","required":false}

json.unwrapped

Control whether fields annotated with @JsonUnwrapped should be flattened into the parent object:

json.unwrapped=true

When enabled, fields from nested objects are merged into the parent instead of appearing as a nested object.

field.max.depth

Limit the depth of nested object expansion to prevent infinite recursion:

field.max.depth=10

param.max.depth

Limit the depth of nested object expansion for parameters:

param.max.depth=5