OpenAPI design, documentation and testing toolset by SmartBear — author specs, generate SDKs/server stubs and publish interactive API portals.
Pricing: 19 USD · Updated 2026-09-03
developmentYes. Swagger Editor, UI and Codegen are open source and free to use. Commercial SmartBear plans start at $19/user/month for design, docs and portal (price checked 2026-09-03).
Swagger is an OpenAPI design, documentation and testing toolset — author specs, generate client SDKs and server stubs in dozens of languages, and publish interactive API portals.
What an API is, how REST APIs work over HTTP, the methods you'll actually meet — GET, POST, PUT, PATCH, DELETE — and how to read a response.
What HTTP request methods are, what each one does, and the difference between GET, POST, PUT, PATCH, DELETE and the rest — with safe vs idempotent.
Cross-Origin Resource Sharing (CORS) is the mechanism browsers use to allow or block requests between different origins. This guide explains how CORS works, why it exists, common errors, and how to fix them.
Step-by-step implementation of JWT authentication on a Node.js/Express API: password hashing, login endpoint, token verification middleware, refresh tokens, and the common security pitfalls.
Rate limiting protects Node.js APIs from abuse and overload. This guide explains fixed window, sliding window, and token bucket algorithms, shows how to add rate limiting to an Express API, and how to test it.
A webhook is a user-defined HTTP callback: one service sends an HTTP request to a URL you control when an event happens. Learn how they work, how they differ from polling and regular APIs, and how to verify signatures and handle retries safely.
The Web Crypto API gives every browser a built-in cryptography engine. Learn how to hash data, sign and verify messages, and encrypt or decrypt content using SubtleCrypto — with practical code examples and security notes.
GraphQL is an open-source query language for APIs that lets clients request exactly the data they need. This guide explains how GraphQL works, its type system, queries and mutations, and how it compares to REST.
REST and GraphQL are two ways to build web APIs. REST uses fixed endpoints and HTTP methods; GraphQL uses a single endpoint where clients query exactly the fields they need. Compare the trade-offs and learn how to choose.
REST and gRPC are two ways to build APIs. REST uses HTTP and JSON with universal browser support; gRPC uses HTTP/2 and Protocol Buffers for binary efficiency and code-generated stubs. Compare the trade-offs and learn when to choose each.
GraphQL and gRPC are two modern ways to build APIs. GraphQL lets clients query exactly the fields they need over a single HTTP endpoint; gRPC calls typed remote methods over HTTP/2 with binary Protocol Buffers. Compare the trade-offs and learn when to choose each.
JSON (JavaScript Object Notation) is an open, language-independent, text-based data interchange format derived from JavaScript object syntax. It represents data as a small set of types — objects, arrays, strings, numbers, booleans, and null — and is the de facto format for web APIs, configuration files, and data exchange between servers and clients. This guide explains JSON's syntax, its data types, how it compares to XML and YAML, and how to parse and generate it.
A regular expression (regex or regexp) is a sequence of characters that forms a search pattern for matching and manipulating text. Built on a formal mathematical foundation and common to almost every programming language and tool, regex lets you validate input, find and replace text, extract data, and transform strings with a compact, declarative syntax. This guide explains what regex is, its core syntax, how it is implemented, and how to use it safely.
How to design a clean REST API: plural resource URLs, safe and idempotent HTTP methods, meaningful status codes, pagination, and error responses — with practical examples.
Protocol Buffers (protobuf) is Google's language-neutral, platform-neutral data serialization format. Define your data once in a .proto file, compile it, and get fast, compact binary output. Learn how protobuf works and when it outperforms JSON.
