Overview

Generate JSON Schema from Scala classes

The goal of this library is to make JSON Schema generation done the way all popular JSON reading/writing libraries do. Inspired by Coursera Autoschema but uses Scala Macros instead of Java Reflection.

Features

• Supports Json Schema draft-04, draft-06, draft-07
• Supports value classes
• Supports sealed trait enums
• Supports sealed trait case classes
• Treats Option as optional fields
• As well as treats fields with default values as optional
• Any Iterable will be treated as array
• Pluggable Joda-Time Support
• Pluggable Cats Support
• Pluggable Refined Support
• Supports generic data types

Example

Suppose you have defined this data structures

sealed trait Gender

object Gender {

    case object Male extends Gender

    case object Female extends Gender
}

case class Company(name: String)

case class Car(name: String, manufacturer: Company)

case class Person(
    firstName: String,
    middleName: Option[String],
    lastName: String,
    gender: Gender,
    birthDay: java.time.LocalDateTime,
    company: Company,
    cars: Seq[Car])

Now you have several ways to specify your schema.

In-Lined

In simple words in-lined mode means you will have no definitions. Type you want to use as source for schema will be represented in json schema without reusable data blocks.

import json._

val personSchema: json.Schema[Person] = Json.schema[Person]

As result you will receive this:

{
  "$schema": "http://json-schema.org/draft-04/schema#",
  "type": "object",
  "additionalProperties": false,
  "properties": {
    "middleName": {
      "type": "string"
    },
    "cars": {
      "type": "array",
      "items": {
        "type": "object",
        "additionalProperties": false,
        "properties": {
          "name": {
            "type": "string"
          },
          "manufacturer": {
            "type": "object",
            "additionalProperties": false,
            "properties": {
              "name": {
                "type": "string"
              }
            },
            "required": [
              "name"
            ]
          }
        },
        "required": [
          "name",
          "manufacturer"
        ]
      }
    },
    "company": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "name": {
          "type": "string"
        }
      },
      "required": [
        "name"
      ]
    },
    "lastName": {
      "type": "string"
    },
    "firstName": {
      "type": "string"
    },
    "birthDay": {
      "type": "string",
      "format": "date-time"
    },
    "gender": {
      "type": "string",
      "enum": [
        "Male",
        "Female"
      ]
    }
  },
  "required": [
    "company",
    "lastName",
    "birthDay",
    "gender",
    "firstName",
    "cars"
  ]
}