Generate sample Json output from Json Schema

Question

I want to know whether there is a method in which I can generate sample json output based on a json schema input. For example of the following input:

{
  "title": "Example Schema",
  "type": "object",
  "properties": {
    "firstName": {
      "type": "string"
    },
    "lastName": {
      "type": "string"
    },
    "age": {
      "description": "Age in years",
      "type": "integer",
      "minimum": 0
    }
  },
  "required": ["firstName", "lastName"]
}

Output:

{
  "firstName": "RandomFirstName",
  "lastName": "RandomLastName"
}

I have a large json schema with plenty of validations, so to generate a sample valid json, I could either create one manually using either Java or just a type it into a file. Is there a better way available?

Do you want a bespoke solution written in Java, to write output to a file? What have you tried already? — Nick Grealy
– Nick Grealy, Commented Feb 19, 2014 at 23:46
Preferably I wanted a java library but I am would take any format form a standalone script to an online tool. I have not yet started writing my own solution problem.I thought better to check if there is some existing library which does that — Abhijeet Kushe
– Abhijeet Kushe, Commented Feb 20, 2014 at 3:19
do we have the .NET or .NET CORE solution for this purpose? — Shawn
– Shawn, Commented Sep 9, 2020 at 6:30
@AbhijeetKushe have you found any java library capable to do that — pacman
– pacman, Commented Feb 2, 2021 at 6:35
No i did not.This was a long time back.It can be scripted but I realized later on it is not worth it.It is a good hackathon project but wont be useful for unit testing.It is always better to have a clear expected output and input as tests serve as documentation.For integration test we can always using templating language like freemarker or Velocity to achieve what we want.Java never added string interpolation like Groovy, scala so 3rd libraries would be needed — Abhijeet Kushe
– Abhijeet Kushe, Commented Feb 2, 2021 at 18:27

surfmuggle · Accepted Answer · 2024-02-18 10:08:09Z

54

You can try the JSON Schema Faker. It will take a schema and generate/output a JSON object that will validate against the schema.

Code available on githubcom

edited Feb 18, 2024 at 10:08

surfmuggle

6,0408 gold badges58 silver badges96 bronze badges

answered Jul 29, 2016 at 17:19

Eric Olson

2,9851 gold badge22 silver badges22 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Vishwa Pratap Over a year ago

Eric I am looking for any java library for the same json schema to json object convertion.

Eric Olson Over a year ago

I am not familiar with any @VishwaPratap. Good luck!

pacman Over a year ago

@VishwaPratap have you found any alternatives

Dharman · Accepted Answer · 2021-09-07 08:47:10Z

7

My team and I have created an online tool that allows you to parse JSON schema and generate an array of JSON data that complies to the schema. You can save it as .json file and parse it to your app with a Java parser.

The tool is called Mock turtle - https://mockturtle.net .

edited Sep 7, 2021 at 8:47

Dharman♦

33.9k27 gold badges106 silver badges157 bronze badges

answered Sep 7, 2021 at 8:41

SkySoft

2132 silver badges10 bronze badges

3 Comments

shizhen Over a year ago

nice tool! Thanks a lot.

Mustafa Ibrahim Over a year ago

Great tool man, I can't stop using it!

valerii15298 Nov 13 at 2:29

Is it open source? If so can you please give a GitHub link?

surfmuggle · Accepted Answer · 2024-02-18 10:05:12Z

7

fake-schema-cli is a JavaScript option you can use.

Example: fake-schema file-input-schema.json > output.json.

edited Feb 18, 2024 at 10:05

surfmuggle

6,0408 gold badges58 silver badges96 bronze badges

answered Nov 11, 2020 at 22:56

Guido

47.9k28 gold badges127 silver badges177 bronze badges

Comments

Jean-François Fabre · Accepted Answer · 2024-07-26 08:08:12Z

7

JSONBuddy can do this for you. It is a Windows desktop JSON editor and generates live JSON sample data while you are editing your schema.

(note: I am the author)

edited Jul 26, 2024 at 8:08

Jean-François Fabre♦

141k24 gold badges179 silver badges246 bronze badges

answered Dec 11, 2017 at 9:56

Clemens

1,83212 silver badges20 bronze badges

Comments

StingyJack · Accepted Answer · 2025-01-22 20:25:51Z

0

Notepad++ has a plugin named "JSON Tools" that will generate a random json document for the schema file in the active document tab. There are not a lot of options, but it does work well in a pinch.

answered Jan 22 at 20:25

StingyJack

19.6k11 gold badges69 silver badges126 bronze badges

Comments

Ted_Zactly · Accepted Answer · 2018-12-10 20:05:11Z

-1

You can also use the ModelObject in Adobe Ride (full disclosure: self-plug here). Point the ModelObject (or a subclass thereof) to a schema in your java project resources: https://github.com/adobe/ride/blob/develop/sample/sample-service-extension/src/test/java/com/adobe/ride/sample/tests/ObjectCreation.java#L38

You can also use the Ride Fuzzer Lib to easily tests sending negative data into the schema nodes (based on an array of OWASP and google injection test strings, and other various types data): https://github.com/adobe/ride/tree/develop/libraries/ride-fuzzer-lib

All Ride modules are open source and free: https://github.com/adobe/ride/

answered Dec 10, 2018 at 20:05

Ted_Zactly

1671 silver badge3 bronze badges

Collectives™ on Stack Overflow

Generate sample Json output from Json Schema

6 Answers 6

3 Comments

3 Comments

Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

6 Answers 6

3 Comments

3 Comments

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related