System Initiative

# Qualification Functions Qualification functions are a kind of [function](./function.md) that validates [component](./components.md) configuration by checking whether the component meets specific requirements or constraints. They provide real-time feedback about configuration issues, policy compliance, or resource availability before you attempt to create or modify infrastructure. ## How Qualification Functions Work Qualification functions examine a component's configuration, generated code, and resource state to determine if it meets certain criteria. They return one of three results: - **Success**: The component passes validation - **Warning**: The component has issues but isn't critically broken - **Failure**: The component has critical problems that should be addressed Qualification results appear as colored indicators on components in the web UI, giving you immediate visual feedback about configuration quality. ## When Qualification Functions Run Qualification functions execute automatically: - When a component is created - When component properties change - After code generation functions complete (if the qualification depends on generated code) - On HEAD, when you explicitly run qualifications to check the actual resource state Unlike most functions, qualifications can run on HEAD without going through a change set, since they only read state and don't modify resources. ## Qualification Function Arguments Qualification functions take a `component` argument with these properties: - `code`: Generated code available as a map keyed by code generation function name - `domain`: The component's domain properties - `resource`: Resource information from previous actions - `deleted_at`: Timestamp string if the component has been deleted This gives qualifications access to all component and resource data, allowing them to validate the configuration comprehensively, both for the model and the real world. ## Qualification Function Return Value Qualifications return an object with two properties: ```typescript return { result: "success", // or "warning" or "failure" message: "Configuration is valid", }; ``` The `result` determines the visual indicator shown on the component, while the `message` provides details about the reasons for the result. ## Common Use Cases Qualification functions are commonly used for: - **Policy validation**: Checking that resources comply with organizational policies (required tags, naming conventions, etc.) - **Resource availability**: Verifying that referenced resources exist (AMI IDs, subnet IDs, etc.) - **Configuration validation**: Ensuring generated code is syntactically valid - **Cloud provider checks**: Running provider-specific validators (AWS IAM Policy Simulator, etc.) - **Dependency verification**: Checking that required resources are present - **Security compliance**: Validating encryption settings, access controls, or other security requirements - **Cost estimation**: Warning about configurations that may be expensive ## Qualifications vs Validations Qualifications differ from simple property validations: - **Property validations**: Check individual properties in isolation (type checking, required fields, etc.) - **Qualifications**: Examine the entire component configuration, generated code, and external state to validate holistically Qualifications can make external API calls, run command-line tools, and perform complex logic that simple property validations cannot. ## Real-World Validation Examples Qualifications can perform sophisticated checks: - **AWS IAM Policy Simulator**: Validate that IAM policies grant the intended permissions - **Docker Registry Check**: Verify that a specified container image exists and is accessible - **Butane Validation**: Ensure that Butane configuration generates valid Ignition files - **DNS Resolution**: Check that domain names resolve correctly - **API Endpoint Testing**: Verify that endpoints are reachable ## Qualifications on HEAD Qualifications are unique in that they can run directly on HEAD without a change set, since they only read state. This allows you to: - Check if resources still exist upstream - Verify that external dependencies are still valid - Monitor compliance over time - Detect configuration drift ## See Also For detailed examples and technical implementation details, see the [Qualification Function Examples](/reference/function#qualification-function-examples) section in the Functions Reference.