fastapi-factory-utilities

name	fastapi-factory-utilities
description	Build FastAPI microservices with plugins, message brokers, OAuth2/OIDC, OpenTelemetry, and structured logging. Use when this capability is needed.
metadata	{"author":"DeerHide"}

FastAPI Factory Utilities

When to use this skill?

• Use this skill when building FastAPI microservices with the fastapi_factory_utilities library.
• Use this skill when implementing plugin-based architectures in FastAPI applications.
• Use this skill when setting up OAuth2/OIDC authentication with Hydra or Kratos.
• Use this skill when configuring MongoDB with Beanie ODM in FastAPI applications.
• Use this skill when implementing RabbitMQ message brokers with AioPika.
• Use this skill when setting up background task processing with Taskiq and Redis.
• Use this skill when configuring OpenTelemetry for distributed tracing and metrics.
• Use this skill when implementing structured logging with structlog.
• Use this skill when using dependency injection patterns with FastAPI's Depends system.
• Use this skill when creating mock resources for testing (AioHttp, ODM repositories).
• Use this skill when implementing repository patterns for data access.
• Use this skill when configuring health checks and status services.
• Use this skill when implementing JWT Bearer authentication with JWKS verification.

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A library for building production-ready FastAPI microservices with plugin-based architecture.

Quick Start

See assets/quick_start_example.py for a minimal application setup.

Dependency Injection and Testing

The library uses FastAPI's Depends for dependency injection. Plugins expose resources via dependency functions (e.g., AioHttpResourceDepends, depends_status_service, depends_scheduler_component).

For testing, several plugins provide mockers to create mock resources:

• AioHttp: build_mocked_aiohttp_resource, build_mocked_aiohttp_response - Mock HTTP clients and responses
• ODM: AbstractRepositoryInMemory - In-memory repository for unit testing without MongoDB
• See AioHttp reference and Repository Pattern for detailed mocking examples

Reference Documentation

Core

Reference	Description
Application Framework	ApplicationAbstract, builders, plugin lifecycle
Configuration	YAML loading, environment variables, type-safe config
Logging	Structured logging with structlog
Status Service	Health and readiness monitoring

Plugins

Reference	Description
ODM Plugin (MongoDB)	MongoDB/Beanie integration, document models
Repository Pattern	Type-safe data access, in-memory testing
AioHttp HTTP Client	HTTP client with connection pooling, mocking utilities
AioPika RabbitMQ	Message publishing and consuming
OpenTelemetry	Distributed tracing and metrics
Taskiq Tasks	Background task processing with Redis

Services

Reference	Description
Hydra Service	OAuth2 token introspection, JWKS, client credentials
Kratos Service	Identity management, session validation
Audit Service	Event auditing with RabbitMQ

Security

Reference	Description
JWT Authentication	JWT Bearer validation, JWKS store, custom verifiers

Utilities

Reference	Description
Pagination	Type-safe pagination types
Ory Utilities	Ory API pagination helpers

Best Practices

1. Plugin Order - Load plugins in dependency order (ODM before repositories)
2. Configuration - Use YAML files with ${ENV_VAR:default} syntax
3. Lifecycle - Keep configure() lightweight, use on_startup() for connections
4. Observability - Enable OpenTelemetry in production
5. Logging - Use JSON mode in production for log aggregation
6. Testing - Use mockers from aiohttp plugin for HTTP client tests

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Source: DeerHide/fastapi_factory_utilities — distributed by TomeVault.