litenode/core/utils/bodyParser.js

Lightweight and modular web framework

import { meros } from "./meros.js"

export const bodyParser = (handlers, customMaxRequestSize) => async (req, res) => {
	let body = ""
	const contentType = req.headers["content-type"]
	const maxRequestSize = customMaxRequestSize ? customMaxRequestSize * 1024 * 1024 : 1024 * 1024

	if (req.headers["content-length"] > maxRequestSize) {
		res.writeHead(413)
		return res.end("Request Entity Too Large")
	}

	if (/^multipart\/form-data/.test(contentType)) {
		function getFileName(headers) {
			const contentDisposition = headers["content-disposition"]
			const fileNameMatch = /filename="([^"]+)"/.exec(contentDisposition)
			return fileNameMatch ? fileNameMatch[1] : null
		}

		const chunks = await meros(req, { multiple: true })
		const data = {}

		for await (const parts of chunks) {
			for (const part of parts) {
				const contentDisposition = part.headers["content-disposition"]
				const nameMatch = contentDisposition.match(/name="([^"]+)"/)

				if (nameMatch) {
					const partName = nameMatch[1]
					const contentType = part.headers["content-type"]
					if (!data[partName]) {
						data[partName] = []
					}
					data[partName].push({
						headers: part.headers,
						body: part.body,
						filename: getFileName(part.headers),
						contentType: contentType,
					})
				}
			}
		}

		req.body = data
		await handlers[handlers.length - 1](req, res, data)
	} else {
		req.on("data", (chunk) => {
			body += chunk.toString()
			if (body.length > maxRequestSize) {
				req.connection.destroy()
			}
		})

		req.on("end", async () => {
			try {
				let data
				if (/^application\/json/.test(contentType)) {
					data = JSON.parse(body)
				} else if (/^application\/x-www-form-urlencoded/.test(contentType)) {
					data = parseFormUrlEncoded(body)
				} else {
					res.writeHead(415)
					return res.end("Unsupported Media Type")
				}
				req.body = data
				await handlers[handlers.length - 1](req, res, data)
			} catch (error) {
				console.error("Error parsing data:", error)
				res.writeHead(400)
				res.end("Invalid data")
			}
		})
	}
}

const parseFormUrlEncoded = (body) => {
	const params = new URLSearchParams(body)
	const data = {}

	for (const [key, value] of params.entries()) {
		assignNestedProperty(data, key, value)
	}

	return data
}

const assignNestedProperty = (obj, key, value) => {
	const keys = key.match(/[^[\]]+/g) // Split the key by [ and ] to get nested keys
	keys.reduce((acc, currentKey, index) => {
		if (index === keys.length - 1) {
			acc[currentKey] = value // Assign the value to the last key
		} else {
			acc[currentKey] = acc[currentKey] || {} // Create nested object if it doesn't exist
		}
		return acc[currentKey]
	}, obj)
}