template-web-astro/src/main.ts

import { objectMap, objectOmit } from '@dzeio/object-util'
import { exec as execAsync } from 'child_process'
import express from 'express'
import fs from 'fs/promises'
import { evaluate } from 'mathjs'
import util from 'util'
import { createErrorResponse } from './HTTPError'
import { getParams } from './gcodeUtils'

const exec = util.promisify(execAsync)
const server = express()

async function exists(file: string) {
	try {
		await fs.stat(file)
		return true
	} catch {
		return false
	}
}

// make the files dir

server.use((req, _, next) => {
    let data: Array<any> = []
    // req.setEncoding()
    req.on('data', function(chunk) {
       data.push(Buffer.from(chunk))
    });

    req.on('end', function() {
        req.body = Buffer.concat(data);
        next();
    });
});

const path = process.cwd()

server.get('/', (_, res) => {
	res.send('please read the README.md file...')
})

server.post('/', async (req, res) => {
	const file = (Math.random() * 1000000).toFixed(0)
	console.log('started processing new request', file)
	await fs.mkdir('files', { recursive: true })
	
	const overrides = objectOmit(req.query, 'algo', 'config')
	let config = `${path}/configs/` + (req.query?.config ?? 'config') + '.ini'
	if (!exists(config)) {
		console.log('request finished in error :(', file)
		return createErrorResponse(res, {
			title: 'Configuration file does not exist',
			status: 404,
			detail: `The configuration file you want to use does not exist`,
			config: req.query?.config ?? 'config'
		})
	}
	const stlPath = `${path}/files/${file}.stl`
	const gcodePath = `${path}/files/${file}.gcode`
	// console.log(stlPath, req.body)
	await fs.writeFile(stlPath, req.body, {
		encoding: null
	})
	// console.log(fs.statSync(stlPath).size, req.body.length)
	let additionnalParams = objectMap(overrides, (v, k) => `--${(k as string).replace(/_/g, '-')} ${v}`).join(' ')
	const slicer = process.env.SLICER_PATH ?? 'prusa-slicer'
	if (slicer.includes('prusa')) {
		additionnalParams += ' --export-gcode'
	}
	const cmd = `${slicer} ${stlPath} --load ${config} --output ${gcodePath} ${additionnalParams}`
	try {
		await exec(cmd, {
			timeout: 60000
		})
	} catch (e: any) {
		console.log('request finished in error :(', file)
		const line = e.toString()
		console.error(e)
		if (line.includes('Objects could not fit on the bed')) {
			await fs.rm(stlPath)
			return createErrorResponse(res, {
				title: 'Object is too large to fit on the bed',
				status: 413,
				detail: `The object you are trying to slice is too large to fit on the current bed`
			})
		} else if (line.includes('No such file')) {
			await fs.rm(stlPath)
			return createErrorResponse(res, {
				title: 'Configuration file does not exist',
				status: 404,
				detail: `The configuration file you want to use does not exist`,
				config: req.query?.config ?? 'config'
			})
		} else if (line.includes('Unknown option')) {
			await fs.rm(stlPath)
			return createErrorResponse(res, {
				title: 'An override does exist',
				status: 404,
				detail: `One or more of your overrides are not available in the current slicer`,
				overrides: overrides

			})
		} else if (line.includes('ETIMEDOUT') || line.includes('Command failed')) {
			await fs.rm(stlPath)
			return createErrorResponse(res, {
				title: 'File is taking too long to process',
				status: 400,
				detail: `The file you are trying to process is too large (${req.body.length}o) to be processed in less than 60 secs`,
				fileId: file,
				config: req.query?.config ?? 'config',
				fileSize: req.body.length,
				overrides: overrides
			})
		}
		return createErrorResponse(res, {
			title: 'General I/O error',
			status: 500,
			detail: `A server error make it impossible to slice the file`,
			fileId: file,
			config: req.query?.config ?? 'config',
			fileSize: req.body.length,
			overrides: overrides,
			serverMessage: e.toString().replace(cmd, '<i>software</i>').replace(stlPath, `<i>file ${file}</i>`).replace(`${path}/configs/`, '').replace('.ini', '')
		})
	}
	const gcode = await fs.readFile(gcodePath, 'utf-8')
	await fs.rm(stlPath)
	await fs.rm(gcodePath)
	const params = getParams(gcode)
	let price = -1
	if (req.query?.algo) {
		let algo = req.query.algo as string
		// objectLoop(params, (value, key) => {
		// 	if (typeof value !== 'number') {
		// 		return
		// 	}
		// 	while (algo.includes(key)) {
		// 		algo = algo.replace(key, value.toString())
		// 	}
		// })
		price = evaluate(algo, params)
	}
	res.json({
		price: parseFloat(price.toFixed(2)),
		...getParams(gcode),
		gcode
	})
	console.log('request successfull :)', file)
	// res.sendFile(gcodePath)
})

server.listen(3000, () => {
	console.log(`🚀 Server ready at localhost:3000`);
})