jsonschema

This library contains the functions for testing the compliance of a value with a JSON schema.

jsonschema.isCompliant(validationSubject, JsonObject jsonSchema)

isCompliant(validationSubject, OBJECT schema): This function tests the validationSubject for compliance with the with the provided JSON schema schema.

The schema itself cannot be validated and improper schema definitions may lead to unexpected results. If validationSubject is compliant with the schema, the function returns true, else it returns false.

Note: The schema is expected to comply with: JSON Schema 2020-12

Example:

policy "example"
permit
where
  var jsonSchema = {
                     "type": "boolean"
                   };
  jsonschema.isCompliant(true, jsonSchema) == true;
  jsonschema.isCompliant(123, jsonSchema) == false;

jsonschema.validateWithExternalSchemas(validationSubject, JsonObject jsonSchema, externalSchemas)

validateWithExternalSchemas(validationSubject, OBJECT jsonSchema, ARRAY externalSchemas): This function validates the validationSubject against the provided JSON schema schema and returns a detailed validation result including error details.

The result contains a valid boolean field and an errors array with detailed information about any validation failures. Each error includes the location in the subject (path), a human-readable message, the validation keyword that failed (type), and the schema location (schemaPath).

The schema itself cannot be validated and improper schema definitions may lead to unexpected results. If the jsonSchema contains external references to other schemas, the validation function looks up the schemas in externalSchemas based on explicitly defined $id field in the schemas. If no $id field is provided, the schema will not be detectable.

Note: The schema is expected to comply with: JSON Schema 2020-12

Example:

policy "validate_api_request_with_shared_schemas"
permit action == "api:call"
where
  var addressSchema = {
    "$id": "https://schemas.company.com/address",
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "street": { "type": "string" },
      "city": { "type": "string" },
      "country": { "type": "string", "minLength": 2, "maxLength": 2 }
    },
    "required": ["street", "city", "country"]
  };
  var userSchema = {
    "$id": "https://schemas.company.com/user",
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "userId": { "type": "string", "format": "uuid" },
      "email": { "type": "string", "format": "email" },
      "role": { "enum": ["user", "admin", "auditor"] },
      "address": { "$ref": "https://schemas.company.com/address" }
    },
    "required": ["userId", "email", "role"]
  };
  var result = jsonschema.validateWithExternalSchemas(
    resource.userData,
    userSchema,
    [addressSchema]
  );
  result.valid || result.errors[0].type == "required";

jsonschema.validate(validationSubject, JsonObject jsonSchema)

validate(validationSubject, OBJECT schema): This function validates the validationSubject against the provided JSON schema schema and returns a detailed validation result.

The result contains a valid boolean field and an errors array with detailed information about any validation failures. Each error includes the location in the subject (path), a human-readable message, the validation keyword that failed (type), and the schema location (schemaPath).

The schema itself cannot be validated and improper schema definitions may lead to unexpected results.

Note: The schema is expected to comply with: JSON Schema 2020-12

Example:

policy "validate_document_metadata"
permit action == "upload:document"
where
  var metadataSchema = {
    "type": "object",
    "properties": {
      "classification": { "enum": ["public", "internal", "confidential", "secret"] },
      "owner": { "type": "string", "minLength": 1 },
      "createdAt": { "type": "string", "format": "date-time" }
    },
    "required": ["classification", "owner"]
  };
  var result = jsonschema.validate(resource.metadata, metadataSchema);
  result.valid;

jsonschema.isCompliantWithExternalSchemas(validationSubject, JsonObject jsonSchema, externalSchemas)

isCompliantWithExternalSchemas(validationSubject, OBJECT jsonSchema, ARRAY externalSchemas): This function tests the validationSubject for compliance with the with the provided JSON schema schema.

The schema itself cannot be validated and improper schema definitions may lead to unexcpected results. If validationSubject is compliant with the schema, the function returns true, else it returns false. If the jsonSchema contains external references to other schemas, the validation function looks up the schemas in externalSchemas based on explicitly defined $id field in the schemas. If no $id field is provided, the schema will not be detectable.

Note: The schema is expected to comply with: JSON Schema 2020-12

Example:

policy "example"
permit
where
  var externals = {
        "$id": "https://example.com/coordinates",
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "title": "Coordinates",
        "type": "object",
        "properties" : {
            "x": { "type": "integer" },
            "y": { "type": "integer" },
            "z": { "type": "integer" }
        }
    };
  var schema = {
        "$id": "https://example.com/triangle.schema.json",
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "title": "Triangle",
        "type": "object",
        "properties": {
            "A": { "$ref": "https://example.com/coordinates" },
            "B": { "$ref": "https://example.com/coordinates" },
            "C": { "$ref": "https://example.com/coordinates" }
      };
  var valid = {
           "A" : { "x" : 1, "y" : 2, "z" : 3 },
           "B" : { "x" : 1, "y" : 2, "z" : 3 },
           "C" : { "x" : 1, "y" : 2, "z" : 3 }
        };
  isCompliantWithExternalSchemas(valid, schema, externals) == true;
  var invalid = {
           "A" : { "x" : "I AM NOT A NUMBER I AM A FREE MAN", "y" : 2, "z" : 3 },
           "B" : { "x" : 1, "y" : 2, "z" : 3 },
           "C" : { "x" : 1, "y" : 2, "z" : 3 }
        };
  isCompliantWithExternalSchemas(invalid, schema, externals) == false;