additionalProperties does not have to be "either a Boolean or a Schema instance"

[MosheElisha]

Currently, the code enforces that "additionalProperties must be either a Boolean or a Schema instance".

According to https://swagger.io/docs/specification/data-models/dictionaries/ and OAI/OpenAPI-Specification#668 (comment), the following structure is also valid:

type: object
additionalProperties:
  type: string

This is the openapi that represents (and is generated) when the model is a Map of string and string (Map<String, String>).

[frantuma]

The enforced behaviour/structure does not seem contradictory to me:

 additionalProperties:
  type: string

is implemented/deserialized in swagger-core with additionalProperties being a Schema with type = "string" (StringSchema)

[MosheElisha]

Thanks, @frantuma .

Perhaps you are right but when I try to load a valid openapi.json.txt into a io.swagger.v3.oas.models.OpenAPI - I get the below exception.

We are reading the json into OpenAPI in order to test and validate the auto generated openapi.json.

Running with a debugger, we can see that the additionalProperties is a instanceof LinkedHashMap and not a instanceof Boolean or instanceof Schema.

...
Caused by: com.fasterxml.jackson.databind.JsonMappingException: additionalProperties must be either a Boolean or a Schema instance
 at [Source: (PushbackInputStream); line: 1245, column: 13] (through reference chain: io.swagger.v3.oas.models.OpenAPI["components"]->io.swagger.v3.oas.models.Components["schemas"]->java.util.LinkedHashMap["CreateDynamicOrderRequest"]->io.swagger.v3.oas.models.media.Schema["properties"]->java.util.LinkedHashMap["customAttributes"]->io.swagger.v3.oas.models.media.Schema["additionalProperties"])
	at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:274)
	at com.fasterxml.jackson.databind.deser.SettableBeanProperty._throwAsIOE(SettableBeanProperty.java:623)
	at com.fasterxml.jackson.databind.deser.SettableBeanProperty._throwAsIOE(SettableBeanProperty.java:611)
	at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:143)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:402)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:195)
	at com.fasterxml.jackson.databind.deser.std.MapDeserializer._readAndBindStringKeyMap(MapDeserializer.java:609)
	at com.fasterxml.jackson.databind.deser.std.MapDeserializer.deserialize(MapDeserializer.java:437)
	at com.fasterxml.jackson.databind.deser.std.MapDeserializer.deserialize(MapDeserializer.java:32)
	at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:129)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:402)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:195)
	at com.fasterxml.jackson.databind.deser.std.MapDeserializer._readAndBindStringKeyMap(MapDeserializer.java:609)
	at com.fasterxml.jackson.databind.deser.std.MapDeserializer.deserialize(MapDeserializer.java:437)
	at com.fasterxml.jackson.databind.deser.std.MapDeserializer.deserialize(MapDeserializer.java:32)
	at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:129)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:402)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:195)
	at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:129)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:402)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:195)
	at com.fasterxml.jackson.databind.deser.DefaultDeserializationContext.readRootValue(DefaultDeserializationContext.java:322)
	at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4591)
	at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3599)
	at org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.readJavaType(AbstractJackson2HttpMessageConverter.java:274)
	... 73 more
Caused by: java.lang.IllegalArgumentException: additionalProperties must be either a Boolean or a Schema instance
	at io.swagger.v3.oas.models.media.Schema.setAdditionalProperties(Schema.java:553)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:564)
	at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:141)
	... 94 more

[frantuma]

I am not sure how you are deserializing and in which scenario, but from your logs it looks like you're using some possibly not configured ObjectMapper; swagger-core provides helper class Json (and similar Yaml) giving access to a correctly configured mapper which - depending on scenario - you would use e.g. like:

Json.mapper().readValue(openApiAsString, OpenAPI.class);

Please close ticket if this answers your question

[MosheElisha]

@frantuma Perfect. Thank you. I was using a default ObjectMapper. Using io.swagger.v3.core.util.Json it worked properly.

[michaelwangwangwang]

good

[GeniusDP]

Works

[mynameiswangyang]

nice

[aditambi]

working