CODEWITHSUNDEEP
javascriptnode.jsjsonjsonschemaajv
Bear Bile Farming is Torture
Bear Bile Farming is Torture

Reputation: 5123

how to validate object schema where the fields depend on each other using ajv?

I am using ajv node package to validate my schemas. Supposed that a field holds an object type.

The object can have 3 properties: "A", "B", and "C".

How do I specify that at least one of these properties must be defined and no other properties are allowed?

Upvotes: 1

Views: 1010

Answers (2)

Byted
Byted

Reputation: 657

Depending on if you want to disallow all other properties or just the specific other ones (if "A" is present, "B" and "C" are forbidden but "foo" is still OK) you can either use oneOf with the additionalProperties: false property or use not to disallow specific properties. Example for both:

schmema:

{
  "anyOf": [
    {
      "properties": {"A": {}},
      "required": ["A"],
      "additionalProperties": false
    },
    {
      "properties": {
        "B": {},
        "A": { "not": {} },
        "C": { "not": {} }
      },
      "required": ["B"],
    }
  ]
}

Note: The pattern "not": {} is always false so no value for the corresponding property can ever fulfill it.

This example uses additionalProperties: false for "A" so it matches

{
      "A": 3
}

but neither

{
    "A": 3,
    "B": 5
}

nor

{
    "A": 3,
    "foo": 5
}

On the other hand, the example uses not for the "B" case so it matches

{
      "B": 3
}

and

{
    "B": 3,
    "foo": 5
}

but not

{
    "A": 3,
    "C": 5
}

Upvotes: 1

Jason Desrosiers
Jason Desrosiers

Reputation: 24399

You can use anyOf for this constraint. The anyOf keyword allows you to combine constraints using a boolean OR operation.

{
  "anyOf": [
    { "required": ["A"] },
    { "required": ["B"] },
    { "required": ["C"] }
  ]
}

Upvotes: 1

Related Questions