# API Framework ## Description API Framework is a layered API software framework designed to provide a structured foundation for building maintainable, scalable, and extensible web services. The framework separates framework capabilities, software capabilities, resource management, request processing, policy enforcement, and runtime execution into clearly defined architectural layers. It provides standardized request handling, response generation, execution pipelines, reusable utility services, and runtime orchestration while maintaining strict ownership boundaries between framework and software components. The framework supports: - API request routing - Request processing - Response generation - Policy-driven execution - Authentication and authorization pipelines - Rate limiting and validation policies - Runtime lifecycle management - Reusable infrastructure services The architecture is organized into four primary layers: - **Data** — Framework and software resources. - **Essential** — Reusable framework capabilities and infrastructure. - **Operational** — Software-specific business capabilities and policies. - **Run** — Runtime initialization, execution, and request processing. This separation enables developers to focus on software behavior while relying on a consistent framework foundation for API processing, security, policy enforcement, utility services, and runtime coordination. --- ## Purpose API Framework exists to provide a consistent, maintainable, and extensible architecture for building API-driven softwares while establishing clear boundaries between framework responsibilities and software responsibilities. ### Objectives - Establish clear separation of concerns. - Standardize API request and response processing. - Distinguish framework-owned and software-owned resources. - Provide reusable infrastructure and utility capabilities. - Centralize policy enforcement and access control. - Simplify software development through a structured architecture. - Improve maintainability and scalability. - Enable controlled software extensibility. - Protect internal framework implementation details. - Encourage consistent API design and execution patterns. ### Design Principles #### Layered Architecture Each architectural layer is responsible for a specific concern and communicates through clearly defined boundaries. #### Ownership Separation Framework-owned capabilities remain separate from software-owned capabilities to prevent implementation leakage and architectural drift. #### Extensibility Softwares extend the framework through approved extension surfaces without modifying framework internals. #### Reusability Common functionality is implemented once and reused throughout both framework and software layers. #### Encapsulation Internal framework implementation details remain hidden behind stable interfaces. #### Policy-Driven Execution Request processing and business operations are governed through dedicated execution pipelines and policy enforcement mechanisms. #### Consistency Request handling, response generation, execution patterns, and resource management follow standardized conventions throughout the framework. --- ## Architecture ### High-Level Structure ```text source ├── data ├── essential ├── operational └── run ``` The architecture is organized into four primary layers that collectively provide resource management, reusable framework capabilities, software capabilities, policy enforcement, and runtime execution. --- ### Data Layer The Data Layer stores all framework-owned and software-owned resources. ```text source/data ├── framework │ ├── metadata │ └── glossary └── software ├── metadata └── glossary ``` #### Responsibilities - Store framework metadata and configuration resources. - Store framework glossary and terminology resources. - Store software metadata and configuration resources. - Store software glossary and terminology resources. - Provide centralized resource ownership boundaries. #### Ownership | Area | Owner | |--------|--------| | data/framework | Framework | | data/software | Software | --- ### Essential Layer The Essential Layer contains reusable framework capabilities, infrastructure services, request processing capabilities, and shared functionality. ```text source/essential ├── exchange ├── hidden └── visible ``` --- ### Essential Exchange Provides the framework API interaction model. ```text exchange ├── router ├── request ├── response └── imperative ``` #### Responsibilities - API request routing. - Request processing. - Response generation. - Imperative execution. - Framework-level API orchestration. --- ### Essential Hidden Contains internal framework capabilities that are not intended for software consumption. ```text hidden └── service └── management ``` #### Management Framework runtime management capabilities. ```text management ├── initialize ├── lifecycle ├── config ├── monitor └── cleaner ``` ##### Initialize Responsible for framework and runtime initialization. ##### Lifecycle Responsible for: - Startup - Shutdown - Restart operations ##### Config Responsible for runtime configuration management. ##### Monitor Responsible for runtime health and operational monitoring. ##### Cleaner Responsible for maintenance and cleanup operations. #### Responsibilities - Runtime initialization. - Lifecycle management. - Runtime configuration. - Monitoring and observability. - Maintenance operations. --- ### Essential Visible Contains reusable framework capabilities available to softwares. ```text visible └── service └── helper ``` Available helper capabilities include: ```text retriever status log progress filesystem datetime marker key hash cipher codec ``` #### Responsibilities - Resource retrieval. - Status reporting. - Structured logging. - Progress tracking. - Filesystem operations. - Date and time utilities. - Identifier generation. - Key generation. - Hash calculation and comparison. - Encryption and decryption. - Encoding and decoding. --- ### Operational Layer The Operational Layer contains all software-specific behavior, business capabilities, and policy definitions. ```text source/operational ├── exchange ├── pipeline └── service ``` This is the primary software development area. --- ### Operational Exchange Provides the software API interaction model. ```text exchange ├── router ├── request ├── response └── imperative ``` #### Responsibilities - Software request routing. - Software request processing. - Software response generation. - Imperative execution. - Software-level API orchestration. --- ### Operational Pipeline Contains software-defined policy execution capabilities. ```text pipeline └── policy ├── validation └── ratelimit ``` #### Validation Responsible for request validation policies. Examples: - Schema validation - Payload validation - Business rule validation #### Rate Limit Responsible for request throttling and usage control. Examples: - Client limits - Endpoint limits - Resource protection #### Responsibilities - Request validation. - Request throttling. - Policy definition. - Software-specific execution controls. --- ### Operational Service Contains software-specific business capabilities. ```text service └── [service] └── [feature] ``` Example: ```text service ├── user │ ├── create │ └── delete ├── customer │ └── register └── invoice └── generate ``` Feature structure: ```text service └── user └── create ├── function.go └── function-data.json ``` #### Responsibilities - Implement business rules. - Manage software workflows. - Execute domain-specific operations. - Consume reusable framework capabilities. --- ### Runtime Layer The Runtime Layer initializes, secures, coordinates, and executes API requests. ```text source/run ├── exchange ├── pipeline └── main ``` --- ### Runtime Exchange Receives incoming requests and dispatches execution. ```text exchange ├── router ├── request ├── response └── imperative ``` #### Responsibilities - Runtime request handling. - Request dispatching. - Response delivery. - Execution coordination. --- ### Runtime Pipeline Provides execution-time access control and policy enforcement. ```text pipeline ├── access └── policy ``` #### Access Access control pipeline. ```text access ├── authentication └── authorization ``` ##### Authentication Verifies the identity of the request originator. Examples: - API Keys - JWT Tokens - Session Authentication ##### Authorization Determines whether authenticated entities can access requested resources. Examples: - Role-based access control - Permission-based access control - Scope validation #### Policy Responsible for runtime policy enforcement. ```text policy └── enforce.go ``` Responsibilities: - Execute policy decisions. - Enforce validation outcomes. - Enforce access decisions. - Coordinate runtime controls. --- ### Runtime Main Software bootstrap and startup. ```text main └── main.go ``` #### Responsibilities - Framework initialization. - Software initialization. - Runtime startup. - Lifecycle coordination. - API server bootstrap. --- ### Request Lifecycle The framework follows a layered request processing model. ```text Client Request │ ▼ Runtime Exchange │ ▼ Access Pipeline (Authentication / Authorization) │ ▼ Policy Enforcement │ ▼ Software Exchange │ ▼ Software Policies (Validation / Rate Limiting) │ ▼ Software Service │ ▼ Framework Services │ ▼ Resource Layer │ ▼ Response ``` --- ### Ownership Model | Layer | Owner | Responsibility | |---------|---------|---------| | data/framework | Framework | Framework resources | | data/software | Software | Software resources | | essential | Framework | Reusable framework capabilities | | operational | Software | Business capabilities and policies | | run | Framework | Runtime execution and enforcement | --- ### Extension Surface Softwares are expected to extend the framework through the following locations: ```text source/data/software source/operational ``` Softwares should consume reusable framework capabilities from: ```text source/essential/visible ``` Softwares should not directly depend on: ```text source/essential/hidden ``` as these components are considered internal framework implementation details and may change without notice.