Addressing "items" keyword in "type" : "array" declarations.

[jjgenoese]

There does not seem to be a way to programatically access the contents of the "items" keyword. Apologies if the method for doing this is documented elsewhere.

I am working on a project that involves translating different schemas (e.g. AVRO, JSONSchema) to an internal format. To do so I need to "walk" the schema. json-sKema seemed like the right tool to do that, but I am unable to "see" the "items" tag that comes as part of an "array" declaration.

Thanks for any help.

[erosb]

Hello, you may check if a Schema instance is an ItemSchema, and if yes, then read its itemsSchema member (value of the "items" keyword). Or you can create a subclass of SchemaVisitor and override its visitItemsSchema() method (then use schema.accept(yourVisitorObj)). Hope it helps.

[jjgenoese]

Thank you so much for replying so quickly! I'll try this out. I was concerned because it doesn't show up when I walk the getSubschemas() and getPropertySubschemas() objects. If I start at the top CompositeSchema, I should encounter the property whose TypeSchema is "array". Can you suggest a way to navigate to "items" from there? Thanks again.

fieldName:anArray; class:com.github.erosb.jsonsKema.CompositeSchema
==> SubSchemas
==> ==> TypeSchema(type="array", location=line 26, character 6, pointer: #/properties/anArray/type)
==> PropertySchemas

How do I get to "Items". Please ignore this followup question if the answer is documented. Thanks much!!!!

[jjgenoese]

(typo: I mean getPropertySchemas() -- sorry)

[erosb]

Any subschemas inside a CompositeSchema correspond to a single schema keyword. So if you have a json schema like

{
  "type": "array",
  "items": {
    "type": "string"
  }
}

Then it will be parsed into a

CompositeSchema(
  subschemas = listOf(
    TypeSchema(type = "array"),
    ItemsSchema(itemsSchema = CompositeSchema(
      subschemas = listOf(TypeSchema(type = "string"))
    ))
  )
)

(Hope this kotlin notation is readable enough)

[jjgenoese]

Thank you again for working with me on this. I want to use this library.

Whenever I iterate through the CompositeSchema's subschemas and propertySchemas, the ItemSchema doesn't show up.

For example:
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"type": "object",
"properties": {
"anArray" : {
"type" : "array"
"items" : ["string"]
}
}
}

    I recurse through this structure and print everything out I get this 
    
    	==>	 top: CompositeSchema(subschemas=[TypeSchema(type="object", 
==>		==>	 subschema: TypeSchema(type="object", location=line 4, character 13, pointer: #/type)
==>		==>	 propertyschema:anArray: CompositeSchema(subschemas=[TypeSchema(type="array", location=line 7, character 6, pointer: #/properties/anArray/type)], ...
==>		==>		==>	 subschema: TypeSchema(type="array", location=line 7, character 6, pointer: #/properties/anArray/type)

No ItemSchema appears in the subschemas() of CompositeSchema("anArray")

Thanks for your help!!!!

[erosb]

"items" : ["string"] this isn't valid according to json schema 2020-12. I'm surprised it even loads (I would expect it to throw an exception here ).

Please try with "items": { "type": "string" }

[jjgenoese]

Oh man! It works, beautifully!!!! Thank you so much!!!

I am so grateful! Apologies for troubling you with what essentially was a syntax error. Is there any way I can "buy you a coffee" ?

[erosb]

Haha, there is a green "Donate" button on the predecessor project: https://github.com/everit-org/json-schema
I appreciate =)