Page 15 - REST-API

Once several microservices each offer their own REST API, the same cross-cutting logic repeats everywhere: checking authentication, enforcing rate limits, logging requests. An API gateway pulls that logic into one central place, with clear benefits but also new questions about resilience and latency.

A GraphQL API that works in development mode is not yet a production-ready API. Performance traps, security gaps and missing observability only surface under load, exactly when there is little room to react. This checklist closes those gaps before they become a problem.

The choice between OpenAPI-First and Code-First is not a technical decision, it is an organizational one. It depends on team size, product maturity, number of consumers and synchronization requirements. This guide provides a structured decision framework, with concrete tooling recommendations for both approaches.

Error modeling is the neglected part of API design. RFC 9457 Problem Details, domain-specific error codes and polymorphic error schemas make the difference between an API where integrators have to guess what an error means and an API where errors are self-explanatory and machine-processable.

OpenAPI 3.1 is the industry standard for REST API documentation, yet many teams only use a fraction of its capabilities. This guide explains all the essential building blocks: from Info and Paths through Components and Schemas to Security and Callbacks, with complete practical YAML examples.

Passing Magento events to external systems through cron polling wastes real-time capability and puts unnecessary load on the database. This article shows how Magento webhooks can be implemented robustly, transparently and portably across Open Source and Commerce using an observer, a message queue and signed HTTP delivery. The focus is on HMAC signatures, retry strategies and a complete delivery log for production-ready webhook delivery.

An API endpoint that disappears without warning breaks every integration using it and damages external developer teams' trust in the entire API. The Deprecation and Sunset HTTP headers from RFC 8594 offer a standardized way to communicate an upcoming retirement early and in a machine-readable form, so clients can react in time.

Choosing the wrong authentication method costs more than just security, it costs developer time on every single integration. API keys, bearer tokens, OAuth2 and HMAC signed requests each solve a different problem, and knowing the difference lets you make the right call before the first commit.

Without additional protective measures, GraphQL APIs are vulnerable to overloaded queries, introspection attacks, batching DoS, and data leaks through resolvers that are too permissive. This security review shows concrete attack scenarios and the matching countermeasures.

Postman, Insomnia, and curl become optional the moment PhpStorm has a full-featured HTTP client built in. GraphQL queries, REST endpoints, bearer-token authentication, and environment variables for different stages, all right inside the IDE, versioned in the repository, with no tool switching required.