Python Validictory (JSON schema validation): How to OR multiple schemas?

Question

I have multiple schemas, each one for data sub-type:

type_one = {
  "type": "object",
  "properties": {
    "one": "string"
  }
}

type_two = {
  "type": "object",
  "properties": {
    "one": "string",
    "two": "string"
  }
}

What I want is to check if incoming data is "type_one" OR "type_two" or throw an error. Something like this:

general_type = {
  "type": [type_one, type_two]
}

My incomming data is like this:

{
  "one": "blablabla",
  "two": "blebleble",
  ...
}

I have been testing several ways but no success... any ideas? Thx

Answer 1

You can use the property "additionalProperties": False in your object schema to only allow an exact set of keys.

First, let's have valid schema structures:

type_one = {
    "type": "object",
    "additionalProperties": False,
    "properties": {
        "one": {"type": "string"}
    }
}

type_two = {
    "type": "object",
    "additionalProperties": False,
    "properties": {
        "one": {"type": "string"},
        "two": {"type": "string"}
    }
}

general_type = {
    "type": [type_one, type_two]
}

NOTE: the schema from your question is "one": "string" , it should be "one": {"type": "string"}

Here is our input data:

data_one = {
    "one": "blablabla"
}

data_two = {
    "one": "blablabla",
    "two": "blablabla"
}

And here is the validation:

import validictory

# additional property 'two' not defined by 'properties' are not allowed
validictory.validate(data_two, type_one)

# Required field 'two' is missing
validictory.validate(data_one, type_two)

# All valid
validictory.validate(data_one, type_one)
validictory.validate(data_two, type_two)

validictory.validate(data_one, general_type)
validictory.validate(data_two, general_type)

I hope this helps.