Availability to change $ref in all schema

[kirillparfenov]

Hello! First of all I would like to thank you for your library. And want to ask my question.
I generated next schema:

{
  "$schema" : "http://json-schema.org/draft-07/schema#",
  "$ref" : "#/definitions/Request",
  "definitions" : {
    "Request" : {
      "type" : "object",
      "properties" : {
        "requestId" : {
          "type" : "string",
          "format" : "uuid"
        },
        "user" : {
          "type" : "array",
          "items" : {
            "$ref" : "#/definitions/User"
          }
        }
      },
      "additionalProperties" : false,
      "$schema" : "http://json-schema.org/draft-07/schema#"
    },
    "User" : {
      "type" : "object",
      "properties" : {
        "username" : {
          "type" : "string"
        }
      },
      "additionalProperties" : false,
      "$schema" : "http://json-schema.org/draft-07/schema#"
    }
  }
}

Next I separate each definition to single file like:
Base.json

{
  "$schema" : "http://json-schema.org/draft-07/schema#",
  "$ref" : "#/definitions/Request"
}

Request.json

{
   "type":"object",
   "properties":{
      "requestId":{
         "type":"string",
         "format":"uuid"
      },
      "user":{
         "type":"array",
         "items":{
            "$ref":"#/definitions/User"
         }
      }
   },
   "additionalProperties":false,
   "$schema":"http://json-schema.org/draft-07/schema#"
}

User.json

{
   "type":"object",
   "properties":{
      "username":{
         "type":"string"
      }
   },
   "additionalProperties":false,
   "$schema":"http://json-schema.org/draft-07/schema#"
}

And my question is:
Is it possible to set a custom "$ref" value during schema generation?
The ideal naming convention would be: ObjectNode.key + ".json" (e.g., Request.json).
While I could recursively traverse all nested elements to find and replace "$ref" values, I'm wondering if there's a more elegant built-in solution.

Ultimately I would like to see the following picture:
Base.json

{
  "$schema" : "http://json-schema.org/draft-07/schema#",
  "$ref" : "./Request.json"
}

Request.json

{
   "type":"object",
   "properties":{
      "requestId":{
         "type":"string",
         "format":"uuid"
      },
      "user":{
         "type":"array",
         "items":{
            "$ref":"./User.json"
         }
      }
   },
   "additionalProperties":false,
   "$schema":"http://json-schema.org/draft-07/schema#"
}

User.json

{
   "type":"object",
   "properties":{
      "username":{
         "type":"string"
      }
   },
   "additionalProperties":false,
   "$schema":"http://json-schema.org/draft-07/schema#"
}

I found examples ExternalRefAnnotationExample, ExternalRefPackageExample but they didn't solve my problem.

[CarstenWickner]

Hi @kirillparfenov,

Your description sounds pretty much like the use case the ExternalRefPackageExample was meant to demonstrate.
What is missing there?

Especially if you're using the Maven plugin to generate the schema files within a given package, you don't even have to split them up into separate files yourself.

[kirillparfenov]

Hi @CarstenWickner ,
When I'm using CustomDefinition such in ExternalRefPackageExample - it erase all data like this:

{
  "$schema" : "https://json-schema.org/draft/2020-12/schema",
  "$ref" : "#/$defs/Example",
  "$defs" : {
    "Example" : {
      "type" : "object",
      "properties" : {
        "bar" : {
          "$ref" : "http://foo.bar/com.github.victools.jsonschema.examples.ExternalRefPackageExample$Bar.json"
        },
        "foo" : {
          "$ref" : "http://foo.bar/com.github.victools.jsonschema.examples.ExternalRefPackageExample$Foo.json"
        },
        "text" : {
          "type" : "string"
        }
      },
      "$id" : "http://foo.bar/com.github.victools.jsonschema.examples.ExternalRefPackageExample$Example.json"
    }
  }
}

config:

SchemaGeneratorConfig config = new SchemaGeneratorConfigBuilder(SchemaVersion.DRAFT_2020_12, OptionPreset.PLAIN_JSON)
                .with(new ModuleImpl())
                .with(Option.DEFINITIONS_FOR_ALL_OBJECTS)
                .with(Option.DEFINITION_FOR_MAIN_SCHEMA)
                .build();

modified classes:

static class Example {
    public String text;
    public Foo foo;
    public Bar bar;
}

static class Foo {
    public List<Bar> bars;
}

static class Bar {
    public Set<String> tags;
}

But I don't want to create a completely custom definition.
I only need custom definition for "$ref".
And what I'm waiting for:

{
  "$schema" : "https://json-schema.org/draft/2020-12/schema",
  "$ref" : "http://foo.bar/com.github.victools.jsonschema.examples.Example.json",
  "$defs" : {
    "Bar" : {
      "type" : "object",
      "properties" : {
        "tags" : {
          "type" : "array",
          "items" : {
            "type" : "string"
          }
        }
      }
    },
    "Example" : {
      "type" : "object",
      "properties" : {
        "bar" : {
          "$ref" : "http://foo.bar/com.github.victools.jsonschema.examples.Bar.json"
        },
        "foo" : {
          "$ref" : "http://foo.bar/com.github.victools.jsonschema.examples.Foo.json"
        },
        "text" : {
          "type" : "string"
        }
      },
      "$id" : "http://foo.bar/com.github.victools.jsonschema.examples.ExternalRefPackageExample$Example.json"
    },
    "Foo" : {
      "type" : "object",
      "properties" : {
        "bars" : {
          "type" : "array",
          "items" : {
            "$ref" : "http://foo.bar/com.github.victools.jsonschema.examples.Bar.json"
          }
        }
      }
    }
  }
}

and after that I can separate defs to files.

I'm writing my custom maven-plugin which scan specific annotation on method's params and creates schema for such params.

upd.
Now I looked at the implementation of your maven plugin again and maybe I should go the way in your plugin with my custom logic:

1. I found a method parameter with a specific annotation
2. Using classgraph I find all the classes associated with this parameter and for all of them I build schemes according to example ExternalRefPackageExample