APIs

Overview

This section consolidates API-related content across the site: fundamentals, REST design with FastAPI, GraphQL, and enterprise HR system integration (Greenhouse, Workday) with OAuth, retry logic, and rate limiting.

Fundamentals

Understanding and Implementing APIsapisREST, SOAP, GraphQL, gRPC; RESTful principles, status codes, versioning.

REST & FastAPI

FastAPI for REST APIsapisPydantic validation, async endpoints, OpenAPI docs, OAuth2/JWT.

Flask

Flask — OverviewflaskMicro-framework design, WSGI, request/response lifecycle, core components, Flask vs FastAPI vs Django. Flask — Benefits & UtilizationflaskFlexibility, extension ecosystem, production utilization patterns, performance characteristics. Flask — Building REST APIsflaskRouting, blueprints, validation, error handling, JWT auth, CORS, rate limiting, OpenAPI with Flask-Smorest. Flask — Sample CodeflaskRunnable CRUD, JWT, file upload, scikit-learn & PyTorch model serving, Celery, SocketIO, app factory. Flask — Production DeploymentflaskGunicorn, nginx, Docker, Kubernetes, 12-factor config, observability, security hardening, zero-downtime…

GraphQL

GraphQL — Advanced Technical DetailsapisSchema typing, single endpoint, client-driven queries.

HR Systems Integration

Greenhouse & Workday API Integrationhr integrationOAuth, retry/backoff, rate limiting, Medallion ingestion, SCD Type 2, anomaly detection.

YouTube API

YouTube Search Engine & Brand-Safety PlatformyoutubeXapian probabilistic search over a multi-billion-video corpus, BM25 ranking, NLP feature extraction,…

Common Cross-Cutting Concerns

Authentication — OAuth 2.0 client-credentials and authorization-code flows; API keys; bearer tokens.
Rate Limiting — Token-bucket and leaky-bucket strategies; respecting Retry-After headers.
Retries — Exponential backoff with jitter; circuit breakers; idempotency keys on mutating calls.
Pagination — Cursor-based, offset-based, and link-header pagination patterns.
Observability — Structured logging, correlation IDs, latency histograms, error-rate SLOs.
Schema Evolution — Versioning strategies (URI vs. header), deprecation policies, backward compatibility.