Providers¶

Overview¶

Providers generate negative test cases for a single OpenAPI operation. Each provider receives a TestGenerationContext that includes the parsed spec, the current operation, and a baseline valid TestCase. Provider execution is orchestrated by ProviderOrchestrator and merged via OutcomeAggregator (see architecture).

For core entry points and extension context, see the core module. For provider interfaces and extension points, see the Test providers SPI. For user-facing configuration (ignore rules, budgets), see YAML config.

Providers operate at two levels: - Operation-level providers decide which OpenAPI element to target (parameters, request body, auth). - Element-level providers (parameter/request body) apply rules to build invalid values.

All providers are executed inside runProviderSafely, which converts exceptions (including BudgetExceededException) into Outcome.Failure results with error context.

Default execution order¶

The default order is defined in TestGeneratorConfigurer.createTestSuiteGenerator:

1. AuthTestCaseProviderForOperation
2. ParameterTestCaseProviderForOperation
3. RequestBodyTestCaseProviderForOperation

The order matters for deterministic output ordering in generated test suites.

Provider catalog¶

Operation-level providers¶

• AuthTestCaseProviderForOperation
• Applies ordered AuthValidationRule instances to generate auth-negative cases.
• Skips when neither the operation nor the root OpenAPI document defines security.

• Expected status codes: 401/403 from built-in auth rules.

• ParameterTestCaseProviderForOperation

• Iterates over operation parameters and invokes parameter providers for each.
• Merges outcomes across parameters and providers.

• Built-in providers generate expectedStatusCode = 400 cases.

• RequestBodyTestCaseProviderForOperation

• Applies request-body providers to the operation request body when present.
• Skips when request body is missing or content is empty after dereference.
• Built-in providers generate expectedStatusCode = 400 cases.

Parameter providers¶

• MissedRequiredParameterTestProvider
• Generates a case that omits a required query/header/cookie parameter.
• Path parameters are excluded (always required by design).
• Applies to Headers: Required non-security header parameters (e.g., X-Request-ID, X-Correlation-ID)
• Does NOT apply to: Security scheme headers (handled by AuthTestCaseProviderForOperation)
• Test Case Pattern: Missed Required {Location} Parameter {name}
• Expected Status Code: 400
• Example Output:

  {
    "name": "Missed Required Header Parameter X-Request-ID",
    "expectedStatusCode": 400,
    "rule": "art.galushko.openapi.testgen.providers.parameter.MissedRequiredParameterTestProvider"
  }
  

• See also: Query Parameter Validation Tests, Header Parameter Validation Tests

• ParameterSchemaValidationTestProvider

• Applies schema validation rules to parameter schemas (including composed schemas).
• Resolves parameter schema from parameter.schema; if absent, falls back to the first parameter.content media type with a schema.
• When both schema and content are defined, logs a warning and uses only schema.
• Supports query/path/header/cookie parameters.
• See also: Path Parameter Validation Tests, Query Parameter Validation Tests, Header Parameter Validation Tests

Request body providers¶

• MissedRequiredRequestBodyTestProvider
• Generates a case with a missing required request body.
• Test Case Name: Required Request Body is missing
• Expected Status Code: 400
• Applies When: requestBody.required: true

• See also: Request Body Schema Tests

• RequestBodySchemaValidationTestProvider

• Applies schema validation rules to the request body schema.
• Processes all supported request-body media types with schemas and deduplicates identical generated cases.
• Supported media types include application/json, text/json, application/jwt, application/xml, text/xml, application/x-www-form-urlencoded, and +json / +jwt / +xml suffixes.
• Unsupported media types are skipped and logged as warnings.
• Test Case Pattern: Incorrect Request Body: {rule description}
• Expected Status Code: 400
• Applies When: Request body has a supported media type and schema constraints
• See also: Request Body Schema Tests

Status codes by provider and rule¶

For scenario-specific guides, see negative testing.

Ignore settings¶

• TestGenerationSettings.ignoreSchemaValidationRules and ignoreAuthValidationRules filter the rule lists before providers run.
• TestGenerationSettings.includeOperations filters paths/methods before generation via IncludeOperationsHandler in TestGenerationProcessor.
• TestGenerationSettings.ignoreTestCases filters test cases after suite assembly via IgnoreConfigHandler (path/method/test-case-level filters).

Budget and error handling¶

• maxSchemaCombinations limits composed-schema expansion via CombinationBudget.
• maxSchemaDepth limits recursion for composed rules (array/object traversal).
• When provider-level budgets are exceeded, providers return Outcome.Failure with a GenerationError rather than throwing.
• maxTestCasesPerOperation is enforced by TestCaseBudgetValidator in the generator layer and throws BudgetExceededException.

Extension points¶

Providers are wired explicitly in TestGeneratorConfigurer. To add, remove, or reorder providers, implement a custom TestSuiteGenerator or supply an alternative wiring layer in a custom engine. Rules remain the primary extension point via TestGenerationModule.extraSimpleSchemaRules and extraAuthRules.