chore: use requestInit instead

src/config.ts

@@ -1,13 +1,55 @@
-export const fetchOptions = {
-  cf: {
-    cacheEverything: true,
-    cacheTtlByStatus: {
-      "200-299": 86400,
-      "400-599": 60,
-    },
-  } satisfies RequestInitCfProperties,
-  headers: {
-    Accept: "text/html, application/xhtml+xml, application/xml;q=0.9, */*;q=0.8",
-    "User-Agent": "Mozilla/5.0 (compatible; Summerflare; +https://github.com/misskey-dev/summerflare)",
-  },
+function parseRFC9110ListsLax(value: string | null): string[] {
+  return (
+    value
+      ?.split(/(?<=^[^"]*|^(?:[^"]*"[^"]*"[^"]*)*),/)
+      .map((value) => value.trim())
+      .filter((value) => value) ?? []
+  )
+}
+
+export function requestInit(request: Request) {
+  const url = new URL(request.url)
+  const cdnLoop = parseRFC9110ListsLax(request.headers.get("CDN-Loop"))
+  if (cdnLoop.some((value) => value.toLowerCase() === url.hostname.toLowerCase() || value.toLowerCase().startsWith(`${url.hostname.toLowerCase()};`))) {
+    throw new Error("CDN Loop Detected")
+  }
+  return {
+    cf: {
+      cacheEverything: true,
+      cacheTtlByStatus: {
+        "200-299": 86400,
+        "400-599": 60,
+      },
+    } satisfies RequestInitCfProperties,
+    headers: {
+      Accept: "text/html, application/xhtml+xml, application/xml;q=0.9, */*;q=0.8",
+      "CDN-Loop": cdnLoop.concat(url.hostname).join(", "),
+      "User-Agent": "Mozilla/5.0 (compatible; Summerflare; +https://github.com/misskey-dev/summerflare)",
+    },
+  }
+}
+
+if (import.meta.vitest) {
+  const { describe, expect, test } = import.meta.vitest
+
+  describe(parseRFC9110ListsLax.name, () => {
+    test("null returns an empty array", () => {
+      expect(parseRFC9110ListsLax(null)).toStrictEqual([])
+    })
+    test("empty string returns an empty array", () => {
+      expect(parseRFC9110ListsLax("")).toStrictEqual([])
+    })
+    test("whitespace only string returns an empty array", () => {
+      expect(parseRFC9110ListsLax("   ")).toStrictEqual([])
+    })
+    test("Cache-Control: max-age=86400, stale-while-revalidate=604800, stale-if-error=86400 returns an array with 3 elements", () => {
+      expect(parseRFC9110ListsLax("max-age=86400, stale-while-revalidate=604800, stale-if-error=86400")).toStrictEqual(["max-age=86400", "stale-while-revalidate=604800", "stale-if-error=86400"])
+    })
+    test('Example-URIs: "http://example.com/a.html,foo", "http://without-a-comma.example.com/" returns an array with 2 elements', () => {
+      expect(parseRFC9110ListsLax('"http://example.com/a.html,foo", "http://without-a-comma.example.com/"')).toStrictEqual(['"http://example.com/a.html,foo"', '"http://without-a-comma.example.com/"'])
+    })
+    test('Example-Dates: "Sat, 04 May 1996", "Wed, 14 Sep 2005" returns an array with 2 elements', () => {
+      expect(parseRFC9110ListsLax('"Sat, 04 May 1996", "Wed, 14 Sep 2005"')).toStrictEqual(['"Sat, 04 May 1996"', '"Wed, 14 Sep 2005"'])
+    })
+  })
 }

src/encoding.ts

@@ -1,5 +1,7 @@
-import { UniversalDetector } from "jschardet/src"
+import { decode } from "html-entities"
+import { UniversalDetector } from "jschardet/src"
 import MIMEType from "whatwg-mimetype"
+import { assign, PrioritizedReference } from "./summary/common"
 
 function getCharset(value: string | null): string | null {
   const type = value === null ? null : MIMEType.parse(value)
@@ -24,17 +26,31 @@ export async function normalize(response: Response): Promise<Response> {
   if (!getCharset(headers.get("content-type"))) {
     const [left, right] = response.body!.tee()
     response = new Response(left, response)
+    const result: PrioritizedReference<string | null> = {
+      bits: 2, // 0-3
+      priority: 0,
+      content: null,
+    }
     const rewriter = new HTMLRewriter()
     rewriter.on("meta", {
       element(element) {
+        const charset = element.getAttribute("charset")
+        if (charset) {
+          const mimeType = new MIMEType("text/html")
+          mimeType.parameters.set("charset", decode(charset))
+          assign(result, 3, mimeType.toString())
+        }
         const httpEquiv = element.getAttribute("http-equiv")?.toLowerCase()
         if (httpEquiv === "content-type") {
-          headers.set(httpEquiv, element.getAttribute("content")!)
+          assign(result, 2, element.getAttribute("content")!)
         }
       },
     })
     const reader = rewriter.transform(new Response(right, response)).body!.getReader()
     while (!(await reader.read()).done);
+    if (result.content) {
+      headers.set("content-type", result.content)
+    }
   }
   if (!headers.has("content-type")) {
     const [left, right] = response.body!.tee()

src/index.ts

@@ -1,5 +1,5 @@
 import { Hono } from "hono"
-import { fetchOptions } from "./config"
+import { requestInit } from "./config"
 import { normalize } from "./encoding"
 import summary from "./summary"
 export interface Env {
@@ -30,10 +30,10 @@ app.get("/url", async (context) => {
   } catch (e) {
     return context.json({ error: "Invalid URL" }, 400)
   }
-  const response = (await fetch(url, fetchOptions)) as any as Response
+  const response = (await fetch(url, requestInit(context.req.raw))) as any as Response
   url = new URL(response.url)
   const rewriter = new HTMLRewriter()
-  const summarized = summary(url, rewriter)
+  const summarized = summary(context.req.raw, url, rewriter)
   const reader = (rewriter.transform(await normalize(response)).body as ReadableStream<Uint8Array>).getReader()
   while (!(await reader.read()).done);
   return context.json(await summarized)
@@ -176,7 +176,7 @@ if (import.meta.vitest) {
     ])("should return summary of %s <%s>", async (_, url, contentType, expected) => {
       const request = new Request(`https://fakehost/url?${new URLSearchParams({ url })}`)
       const ctx = createExecutionContext()
-      const preconnect = await fetch(url, fetchOptions)
+      const preconnect = await fetch(url, requestInit(request))
       expect(preconnect.status).toBe(200)
       expect(preconnect.headers.get("content-type")).toBe(contentType)
       const response = await app.fetch(request, env, ctx)

src/summary/general/index.ts

@@ -8,11 +8,11 @@ import getTitle from "./title"
 import getSensitive from "./sensitive"
 import getPlayer, { Player } from "./player"
 
-export default function general(url: URL, html: HTMLRewriter) {
+export default function general(request: Request, url: URL, html: HTMLRewriter) {
   const card = getCard(url, html)
   const title = getTitle(url, html)
   const image = getImage(url, html)
-  const player = Promise.all([card, getPlayer(url, html)]).then<Player>(([card, parsedPlayer]) => {
+  const player = Promise.all([card, getPlayer(request, url, html)]).then<Player>(([card, parsedPlayer]) => {
     return {
       url: (card !== "summary_large_image" && parsedPlayer.urlGeneral) || parsedPlayer.urlCommon,
       width: parsedPlayer.width,

src/summary/general/player.ts

@@ -16,8 +16,8 @@ export interface ParsedPlayer extends Omit<Player, "url"> {
   urlGeneral: string | null
 }
 
-export default function getPlayer(url: URL, html: HTMLRewriter): Promise<ParsedPlayer> {
-  const oEmbed = getPlayerOEmbed(url, html)
+export default function getPlayer(request: Request, url: URL, html: HTMLRewriter): Promise<ParsedPlayer> {
+  const oEmbed = getPlayerOEmbed(request, url, html)
   const urlGeneral = getPlayerUrlGeneral(url, html)
   const urlCommon = getPlayerUrlCommon(url, html)
   const width = getPlayerUrlWidth(url, html)

src/summary/general/playerOEmbed.ts

@@ -1,6 +1,6 @@
 import { decode } from "html-entities"
 import { z } from "zod"
-import { fetchOptions } from "../../config"
+import { requestInit } from "../../config"
 import { assign, PrioritizedReference } from "../common"
 import type { ParsedPlayer } from "./player"
 
@@ -41,7 +41,8 @@ const oEmbed = z.union([
   }),
 ])
 
-export default function getPlayerOEmbed(url: URL, html: HTMLRewriter) {
+export default function getPlayerOEmbed(request: Request, url: URL, html: HTMLRewriter) {
+  const { promise, resolve, reject } = Promise.withResolvers<ParsedPlayer>()
   const result: PrioritizedReference<ParsedPlayer> = {
     bits: 1, // 0-1
     priority: 0,
@@ -59,7 +60,14 @@ export default function getPlayerOEmbed(url: URL, html: HTMLRewriter) {
       if (!oEmbedHref) {
         return
       }
-      const oEmbedData: unknown = await fetch(oEmbedHref, fetchOptions)
+      let init: RequestInit
+      try {
+        init = requestInit(request)
+      } catch (e) {
+        reject(e)
+        return
+      }
+      const oEmbedData: unknown = await fetch(oEmbedHref, init)
         .then((response) => response.json())
         .catch(() => undefined)
       const { success, data } = oEmbed.safeParse(oEmbedData)
@@ -112,11 +120,10 @@ export default function getPlayerOEmbed(url: URL, html: HTMLRewriter) {
       }
     },
   })
-  return new Promise<ParsedPlayer>((resolve) => {
-    html.onDocument({
-      end() {
-        resolve(result.content)
-      },
-    })
+  html.onDocument({
+    end() {
+      resolve(result.content)
+    },
   })
+  return promise
 }

src/summary/index.ts

@@ -2,12 +2,12 @@ import amazon from "./amazon"
 import general from "./general"
 import wikipedia from "./wikipedia"
 
-export default function summary(url: URL, html: HTMLRewriter) {
+export default function summary(request: Request, url: URL, html: HTMLRewriter) {
   if (url.hostname === "www.amazon.com" || url.hostname === "www.amazon.co.jp" || url.hostname === "www.amazon.ca" || url.hostname === "www.amazon.com.br" || url.hostname === "www.amazon.com.mx" || url.hostname === "www.amazon.co.uk" || url.hostname === "www.amazon.de" || url.hostname === "www.amazon.fr" || url.hostname === "www.amazon.it" || url.hostname === "www.amazon.es" || url.hostname === "www.amazon.nl" || url.hostname === "www.amazon.cn" || url.hostname === "www.amazon.in" || url.hostname === "www.amazon.au") {
     return amazon(url, html)
   }
   if (`.${url.hostname}`.endsWith(".wikipedia.org")) {
     return wikipedia(url, html)
   }
-  return general(url, html)
+  return general(request, url, html)
 }