Schema validation¶

The simplest way to validate an instance under OAS schema is to use the validate function.

Validate¶

To validate an OpenAPI v3.1 schema:

from openapi_schema_validator import validate

# A sample schema
schema = {
    "type": "object",
    "required": [
       "name"
    ],
    "properties": {
        "name": {
            "type": "string"
        },
        "age": {
            "type": ["integer", "null"],
            "format": "int32",
            "minimum": 0,
        },
        "birth-date": {
            "type": "string",
            "format": "date",
        },
        "address": {
             "type": 'array',
             "prefixItems": [
                 { "type": "number" },
                 { "type": "string" },
                 { "enum": ["Street", "Avenue", "Boulevard"] },
                 { "enum": ["NW", "NE", "SW", "SE"] }
             ],
             "items": False,
         }
    },
    "additionalProperties": False,
}

# If no exception is raised by validate(), the instance is valid.
validate({"name": "John", "age": 23, "address": [1600, "Pennsylvania", "Avenue"]}, schema)

validate({"name": "John", "city": "London"}, schema)

Traceback (most recent call last):
    ...
ValidationError: Additional properties are not allowed ('city' was unexpected)

By default, the latest OpenAPI schema syntax is expected.

Validators¶

if you want to disambiguate the expected schema version, import and use OAS31Validator:

from openapi_schema_validator import OAS31Validator

validate({"name": "John", "age": 23}, schema, cls=OAS31Validator)

In order to validate OpenAPI 3.0 schema, import and use OAS30Validator instead of OAS31Validator.

from openapi_schema_validator import OAS30Validator

# A sample schema
schema = {
    "type": "object",
    "required": [
       "name"
    ],
    "properties": {
        "name": {
            "type": "string"
        },
        "age": {
            "type": "integer",
            "format": "int32",
            "minimum": 0,
            "nullable": True,
        },
        "birth-date": {
            "type": "string",
            "format": "date",
        }
    },
    "additionalProperties": False,
}

validate({"name": "John", "age": None}, schema, cls=OAS30Validator)

Read/write context¶

OpenAPI 3.0 schema comes with readOnly and writeOnly keywords. In order to validate read/write context in OpenAPI 3.0 schema, import and use OAS30ReadValidator or OAS30WriteValidator.

from openapi_schema_validator import OAS30WriteValidator

# A sample schema
schema = {
    "type": "object",
    "required": [
       "name"
    ],
    "properties": {
        "name": {
            "type": "string"
        },
        "age": {
            "type": "integer",
            "format": "int32",
            "minimum": 0,
            "readOnly": True,
        },
        "birth-date": {
            "type": "string",
            "format": "date",
        }
    },
    "additionalProperties": False,
}

validate({"name": "John", "age": 23}, schema, cls=OAS30WriteValidator)

Traceback (most recent call last):
    ...
ValidationError: Tried to write read-only property with 23