api

HTTP methods and REST semantics: GET/POST/PUT/PATCH/DELETE verbs, idempotency, safe methods, status-code pairing and common misuses. For choosing the right verb when designing APIs so retries and concurrency behave predictably. Pairs with the HTTP Status Codes sheet.

For developers designing or consuming GraphQL APIs: covers query and mutation syntax, subscriptions, the schema type system, fragments, directives, and pagination — the vocabulary shared by GraphQL clients and servers.

Postman operations covering request building, environment/global variables, test scripts and assertions, pre-request scripts and dynamic data, and collection runs with Mock servers. For debugging APIs beyond a single curl call.

RESTful API design conventions covering URL naming, HTTP method selection, status-code choice, request headers and response formats, auth options and best practices. For designing consistent, debuggable web APIs.

An HTTPie reference: GET/POST requests, automatic JSON formatting, form and file uploads, authentication, and http/s sessions for everyday API testing.