now-flow/src/serverless/get-handler.js

Add deployment workflows to Zeit now

// @flow

// Native
const { readFileSync } = require('fs-extra')
const { join } = require('path')

// Utilities
/*eslint-disable */
const handler = readFileSync(join(__dirname, 'handler.js')).toString()
/*eslint-enable */

// symbols to replace in the meta-source
const CMD_SYMBOL = '/*NOW_CMD*/'
const SCRIPT_SYMBOL = '/*NOW_SCRIPT*/'
const REQ_HANDLER_SYMBOL = '/*PROXY_REQUEST_SOURCE*/'

if (handler.indexOf(CMD_SYMBOL) < 0) {
	throw new Error('Missing symbol in `handler.js`: ' + CMD_SYMBOL)
}

if (handler.indexOf(SCRIPT_SYMBOL) < 0) {
	throw new Error('Missing symbol in `handler.js`: ' + SCRIPT_SYMBOL)
}

if (handler.indexOf(REQ_HANDLER_SYMBOL) < 0) {
	throw new Error('Missing symbol in `handler.js`: ' + REQ_HANDLER_SYMBOL)
}

const getHandler = ({ cmd, script }, fn) =>
	handler
		.replace(CMD_SYMBOL, JSON.stringify(cmd))
		.replace(SCRIPT_SYMBOL, JSON.stringify(script))
		.replace(REQ_HANDLER_SYMBOL, fn.toString())

module.exports = getHandler