From a410bc4264a884e2d130b0fce23ad573e1fda60b Mon Sep 17 00:00:00 2001
From: httpjamesm <github@httpjames.space>
Date: Sat, 12 Nov 2022 10:56:51 -0500
Subject: [PATCH] refactor: use zyachel's code

---
 src/pages/api/media_proxy.ts | 154 +++++------------------------------
 1 file changed, 20 insertions(+), 134 deletions(-)

diff --git a/src/pages/api/media_proxy.ts b/src/pages/api/media_proxy.ts
index 1cffb04..0426087 100644
--- a/src/pages/api/media_proxy.ts
+++ b/src/pages/api/media_proxy.ts
@@ -1,164 +1,50 @@
 import { NextApiRequest, NextApiResponse } from 'next'
-import fetch from 'node-fetch'
 import redis from '../../utils/redis'
-import crypto from 'crypto'
+import axiosInstance from '../../utils/axiosInstance'
+import { AxiosResponse } from 'axios'
 
-const acceptableExtensions = ['.jpg', '.png', '.gif', '.webp', '.mp4']
+const regex =
+  /^https:\/\/((m\.)?media-amazon\.com|imdb-video\.media-imdb\.com).*\.(jpg|jpeg|png|mp4|gif|webp).*$/
 
 export default async function handler(
   req: NextApiRequest,
   res: NextApiResponse
 ) {
-  const userIp =
-    (req.headers['cf-connecting-ip'] as string) ||
-    (req.headers['x-real-ip'] as string) ||
-    req.socket.remoteAddress ||
-    null
+  const mediaUrl = req.query.url as string | undefined
 
-  if (!userIp) {
-    res.status(500)
-    res.json({
+  if (!mediaUrl || !regex.test(mediaUrl))
+    return res.status(400).json({
       success: false,
-      message: 'Unable to enforce ratelimit',
+      message: 'Invalid query',
     })
-    return
-  }
 
-  // hash ip with md5 (for speed)
-  const ipHash = crypto.createHash('md5').update(userIp).digest('hex')
-
-  const key = `ip_ratelimit:${ipHash}`
-
-  // check if ip is in redis
-  let ipInRedis = await redis.get(key)
-
-  if (!ipInRedis) {
-    // if not, set it to 1
-    await redis.setex(key, 30, '1')
-    ipInRedis = '1'
-  }
-
-  const ipReqNumber = Number(ipInRedis)
-
-  if (ipReqNumber > 60) {
-    res.status(429)
-    res.setHeader('x-cringe', 'stop abusing a FOSS service')
-    res.json({
-      success: false,
-      message: 'Too many requests',
-    })
-    return
-  }
-
-  // increment ip in redis
-  await redis.set(key, String(ipReqNumber + 1))
-
-  // get query param
-  const mediaUrl = (req.query as { url: string }).url
-
-  if (!mediaUrl) {
-    res.status(400)
-    res.json({
-      success: false,
-      message: 'Missing query',
-    })
-    return
-  }
-
-  let mediaUrlParsed: URL
-
-  try {
-    mediaUrlParsed = new URL(mediaUrl)
-  } catch {
-    res.status(400)
-    res.json({
-      success: false,
-      message: 'Invalid URL',
-    })
-    return
-  }
-
-  // get media domain
-  const mediaDomain = mediaUrlParsed.hostname
-
-  if (
-    !mediaDomain.endsWith('media-amazon.com') &&
-    mediaDomain !== 'imdb-video.media-imdb.com'
-  ) {
-    res.status(400)
-    res.json({
-      success: false,
-      message: 'Unauthorized domain',
-    })
-    return
-  }
-
-  if (mediaUrlParsed.protocol !== 'https:') {
-    res.status(400)
-    res.json({
-      success: false,
-      message: 'Unauthorized protocol',
-    })
-    return
-  }
-
-  let validExtension = false
-
-  for (const acceptableExtension of acceptableExtensions) {
-    if (mediaUrlParsed.pathname.endsWith(acceptableExtension)) {
-      validExtension = true
-      break
-    }
-  }
-
-  if (!validExtension) {
-    res.status(400)
-    res.json({
-      success: false,
-      message: 'Unauthorized extension',
-    })
-    return
-  }
-
-  // hash mediaUrl with blake3
-  const mediaUrlHash = crypto
-    .createHash('sha256')
-    .update(mediaUrl)
-    .digest('base64')
-
-  // try to find mediaUrlHash in redis
-  const cacheKey = `media_proxy:${mediaUrlHash}`
-
-  const cachedMedia = await redis.get(cacheKey)
+  const cachedMedia = await redis.getBuffer(mediaUrl)
 
   if (cachedMedia) {
-    res.status(302)
     res.setHeader('x-cached', 'true')
-    res.send(cachedMedia)
+    res.status(302).send(cachedMedia)
     return
   }
 
-  res.setHeader('x-cached', 'false')
-
-  // download media
-  const mediaRes = await fetch(mediaUrl)
-
-  if (!mediaRes.ok) {
-    res.status(mediaRes.status)
+  let mediaRes: AxiosResponse
+  try {
+    mediaRes = await axiosInstance(mediaUrl, { responseType: 'arraybuffer' })
+  } catch {
+    res.status(404)
     res.json({
       success: false,
-      message: 'Error from Amazon',
+      message: 'Error from IMDb',
     })
     return
   }
 
-  const mediaBuffer = Buffer.from(await mediaRes.arrayBuffer())
-
+  const data = mediaRes.data
   // save in redis for 30 minutes
-  await redis.setex(cacheKey, 60 * 30, mediaBuffer)
+  await redis.setex(mediaUrl, 30 * 60, Buffer.from(data))
 
   // send media
-  res.send(mediaBuffer)
+  res.setHeader('x-cached', 'false')
+  res.send(data)
 }
 
 export const config = {