Advanced Features

Schema metadata


const schema = new SchemaBuilder()
  .$id("https://example.com/schemas/user.json")
  .$schema("https://json-schema.org/draft/2020-12/schema")
  .title("User Schema")
  .description("Represents a user in the system")
  .object()
  .properties({
    id: (s) => s.integer(),
  })
  .build();

Custom keywords

Add any custom keyword with .option().


const schema = new SchemaBuilder()
  .object()
  .properties({
    status: (s) => s.string(),
  })
  .option("x-custom-validator", "myValidator")
  .option("x-internal", true)
  .build();
// Result includes: "x-custom-validator": "myValidator"

$data references

Enable runtime data references.


const schema = new SchemaBuilder()
  .object()
  .properties({
    minValue: (s) => s.number(),
    maxValue: (s) => s.number(),
    currentValue: (s) =>
      s
        .number()
        .minimum({ $data: "1/minValue" })
        .maximum({ $data: "1/maxValue" }),
  })
  .build();
// currentValue validated against runtime min/max values

Multiple schema IDs


const schema = new SchemaBuilder()
  .$id("https://example.com/base")
  .$defs({
    subSchema: (s) =>
      s
        .$id("sub-schema.json") // relative ID
        .object()
        .properties({
          value: (s) => s.string(),
        }),
  })
  .build();
// Resolves to: https://example.com/sub-schema.json