distinct

The distinct rule ensures that all values of a property inside an array are unique. The validation rule only works with the array schema type.

Assuming you have an array of objects, each defining a product id property and you want to ensure that no duplicates product ids are being used.

Sample Data

{
  "products": [
    {
      "id": 1,
      "quantity": 4,
    },
    {
      "id": 3,
      "quantity": 10,
    },
    {
      "id": 8,
      "quantity": 1,
    }
  ]
}

The rule is applied on the array itself and NOT its members.

Validation rule

import { schema, rules } from '@ioc:Adonis/Core/Validator'

{
  products: schema
    .array([
      rules.distinct('id')
    ])
    .members(schema.object().members({
      id: schema.number(),
      quantity: schema.number(),
    }))
}

You can also use the distinct rule with an array of literal values by using the wildcard * keyword. For example:

Sample Data

{
  "tags": [1, 10, 15, 8]
}

Validation rule

{
  tags: schema
    .array([
      rules.distinct('*')
    ])
    .members(schema.number())
}