Data Generators
Learn how to use the $gen operator to generate dynamic, realistic test data via Faker.js.
Plyson includes a built-in data generation system powered by Faker.js. This allows you to create realistic, unique data for every request without manual setup.
How to Transform Faker.js to JSON
If you are familiar with Faker.js, you can easily translate any method call into Plyson's $gen syntax.
The Basic Formula
Put the method name in the $gen key, and any arguments as top-level keys beside it.
| Faker.js (Code) | Plyson (JSON) |
|---|---|
faker.string.uuid() | { "$gen": "uuid" } |
faker.internet.email() | { "$gen": "email" } |
faker.number.int({ min: 10, max: 100 }) | { "$gen": "int", "min": 10, "max": 100 } |
faker.person.fullName({ sex: 'male' }) | { "$gen": "fullName", "sex": "male" } |
Resolution Modes
Plyson provides three ways to target a specific Faker method:
1. Auto-Discovery
Simply provide the method name. Plyson will search all Faker modules to find a match.
{ "$gen": "email" } 2. Qualified Names
Specify the module and method separated by a dot. Use this if multiple modules have the same method name.
{ "$gen": "vehicle.type" }3. Module Hints
Use the $module key to specify which Faker module to use.
{ "$gen": "type", "$module": "animal" }Advanced Logic
Nested Resolution
You can use variables or even other generators inside the options of a generator.
{
"$gen": "string",
"length": { "$gen": "number", "min": 4, "max": 12 }
}Array Generation ($count)
To generate an array of random values instead of a single one, add the $count key:
{
"tags": { "$gen": "word", "$count": 3 }
}Result: ["apple", "banana", "cherry"]
Example
{
"title": "Register User",
"request": {
"method": "POST",
"endpoint": "/register",
"payload": {
"email": { "$gen": "email" },
"firstName": { "$gen": "firstName" },
"age": { "$gen": "number", "min": 21, "max": 99 }
}
}
}