64 lines
1.7 KiB
TypeScript
64 lines
1.7 KiB
TypeScript
import { NextApiRequest, NextApiResponse } from 'next'
|
|
import { promisify } from 'util'
|
|
import { pipeline } from 'stream'
|
|
import { getFunctionUrl } from 'web/lib/firebase/api-call'
|
|
import fetch, { Headers, Response } from 'node-fetch'
|
|
|
|
function getProxiedRequestHeaders(req: NextApiRequest, whitelist: string[]) {
|
|
const result = new Headers()
|
|
for (const name of whitelist) {
|
|
const v = req.headers[name.toLowerCase()]
|
|
if (Array.isArray(v)) {
|
|
for (const vv of v) {
|
|
result.append(name, vv)
|
|
}
|
|
} else if (v != null) {
|
|
result.append(name, v)
|
|
}
|
|
}
|
|
result.append('X-Forwarded-For', req.socket.remoteAddress || '')
|
|
result.append('Via', 'Vercel public API')
|
|
return result
|
|
}
|
|
|
|
function getProxiedResponseHeaders(res: Response, whitelist: string[]) {
|
|
const result: { [k: string]: string } = {}
|
|
for (const name of whitelist) {
|
|
const v = res.headers.get(name)
|
|
if (v != null) {
|
|
result[name] = v
|
|
}
|
|
}
|
|
return result
|
|
}
|
|
|
|
export const fetchBackend = (req: NextApiRequest, name: string) => {
|
|
const url = getFunctionUrl(name)
|
|
const headers = getProxiedRequestHeaders(req, [
|
|
'Authorization',
|
|
'Content-Length',
|
|
'Content-Type',
|
|
'Origin',
|
|
])
|
|
const hasBody = req.method != 'HEAD' && req.method != 'GET'
|
|
const opts = { headers, method: req.method, body: hasBody ? req : undefined }
|
|
return fetch(url, opts)
|
|
}
|
|
|
|
export const forwardResponse = async (
|
|
res: NextApiResponse,
|
|
backendRes: Response
|
|
) => {
|
|
const headers = getProxiedResponseHeaders(backendRes, [
|
|
'Access-Control-Allow-Origin',
|
|
'Content-Type',
|
|
'Cache-Control',
|
|
'ETag',
|
|
'Vary',
|
|
])
|
|
res.writeHead(backendRes.status, headers)
|
|
if (backendRes.body != null) {
|
|
return await promisify(pipeline)(backendRes.body, res)
|
|
}
|
|
}
|