body-parser

Body-parser is a Node.js body parsing middleware that extracts the body portion of incoming HTTP requests and makes it available under req.body. The middleware supports parsing JSON payloads, URL-encoded form data, raw binary buffers, and plain text bodies. Each parser can be configured with size limits to prevent denial-of-service attacks from oversized request bodies, custom content type matching, and encoding options. The JSON parser handles Content-Type application/json, the urlencoded parser handles application/x-www-form-urlencoded (the default format for HTML form submissions), and the raw and text parsers handle arbitrary binary and text content types respectively. While Express 4.16+ includes built-in body parsing via express.json() and express.urlencoded() (which are actually re-exports of body-parser), the standalone body-parser package is still widely used with other frameworks and in projects that need the raw or text parsers. Body-parser was originally part of Express's core and was extracted into a separate module as part of Express 4's modularization effort.