Hono と Cloudflare Images で Next.js の画像リサイズを再現する

routes = [
  { pattern = "zzz.xxx.yyy/_next/*", zone_name = "xxx.yyy" },
]

import { Hono } from "hono";
import { createFactory, createMiddleware } from "hono/factory";

const preventResizeLoop = createMiddleware((c, next) => {
  const via = c.req.header("via") ?? "";
  // 'via' ヘッダーに 'image-resizing' が含まれる場合、無限ループを防ぐためにリクエストをそのまま返す
  if (/image-resizing/.test(via)) {
    return fetch(c.req.raw);
  }

  return next();
});

const factory = createFactory();
const app = factory.createApp();

const nextImage = factory.createHandlers(preventResizeLoop, async (c) => {
  // URL Parameter から URL と画像の最適化オプション取得
  // 画像最適化
});

app.get("/_next/image", nextImage);
app.get("*", (c) => fetch(c.req.raw));

export default app;

import { z } from "zod";

const Format = z.union([z.literal("avif"), z.literal("webp"), z.literal("jpeg"), z.literal("png")]);

export const TransformOptions = z.object({
  blur: z.coerce.number().min(0).max(250).optional(),

  format: Format.optional(),

  height: z.coerce.number().min(0).optional(),
  h: z.coerce.number().min(0).optional(),

  width: z.coerce.number().min(0).optional(),
  w: z.coerce.number().min(0).optional(),

  quality: z.coerce.number().min(0).max(100).optional(),
  q: z.coerce.number().min(0).max(100).optional(),
});

import { Hono } from "hono";
import { createFactory, createMiddleware } from "hono/factory";
import { zValidator } from "@hono/zod-validator";

import { TransformOptions } from "./schema";

const preventResizeLoop = createMiddleware((c, next) => {
  const via = c.req.header("via") ?? "";
  if (/image-resizing/.test(via)) {
    return fetch(c.req.raw);
  }

  return next();
});

const factory = createFactory();
const app = factory.createApp();

const nextImage = factory.createHandlers(preventResizeLoop, zValidator("query", TransformOptions), async (c) => {
  // 画像最適化
});

app.get("/_next/image", nextImage);
app.get("*", (c) => fetch(c.req.raw));

export default app;

import { Hono } from "hono";
import { createFactory, createMiddleware } from "hono/factory";
import { zValidator } from "@hono/zod-validator";

import { TransformOptions } from "./schema";

const preventResizeLoop = createMiddleware((c, next) => {
  const via = c.req.header("via") ?? "";
  if (/image-resizing/.test(via)) {
    return fetch(c.req.raw);
  }

  return next();
});

const factory = createFactory();
const app = factory.createApp();

const nextImage = factory.createHandlers(
  preventResizeLoop,
  zValidator("query", TransformOptions),
  async (c) => {
    const query = c.req.valid("query");
    const accept = c.req.header("accept") ?? "";

    return fetch(c.req.raw, {
      cf: {
        image: {
          ...query,
          get quality() {
            return query.quality ?? query.q;
          },
          get width() {
            return query.width ?? query.w;
          },
          get height() {
            return query.height ?? query.h;
          },
          get format() {
            if (query.format !== undefined) {
              return query.format;
            }

            if (/image\/avif/.test(accept)) {
              return "avif";
            } else if (/image\/webp/.test(accept)) {
              return "webp";
            }

            return undefined;
          },
        },
      },
    });
  }
);

app.get("/_next/image", nextImage);
app.get("*", (c) => fetch(c.req.raw));

export default app;

"use client";
import NextImage from "next/image";

import {
  useCallback,
  useMemo,
  useState,
  type ComponentPropsWithoutRef,
} from "react";

type Props = ComponentPropsWithoutRef<typeof NextImage>;

const Image = (props: Props) => {
  const [loading, setLoading] = useState(true);
  const handleLoad = useCallback(
    (event: React.SyntheticEvent<HTMLImageElement, Event>) => {
      setLoading(false);
      props?.onLoad?.(event);
    },
    [props],
  );
  const isPlaceholderBlur =
    typeof props.blurDataURL === "string" && props.placeholder === "blur";

  const placeholderStyle = useMemo(
    () =>
      typeof props.blurDataURL === "string" && props.placeholder === "blur"
        ? {
            ...props.style,
            backgroundSize: props.style?.objectFit ?? "cover",
            backgroundPosition: props.style?.objectPosition ?? "50% 50%",
            backgroundRepeat: "no-repeat",
            backgroundImage: `url("${props.blurDataURL}")`,
          }
        : {},
    [props.blurDataURL, props.placeholder, props.style],
  );

  return (
    <NextImage
      {...props}
      onLoad={handleLoad}
      alt={props.alt}
      placeholder={isPlaceholderBlur ? "empty" : props.placeholder}
      style={isPlaceholderBlur && loading ? placeholderStyle : props.style}
    />
  );
};

export default Image;

type BlurOptions = {
  width?: number;
  quality?: number;
  blur?: number;
};

export const formatBlurURL = (
  path: string,
  blurOptions?: BlurOptions,
): string => {
  const searchParams = new URLSearchParams();
  searchParams.set("url", path);
  searchParams.set("w", `${blurOptions?.width ?? 32}`);
  searchParams.set("q", `${blurOptions?.quality ?? 30}`);
  if (blurOptions?.blur !== undefined) {
    searchParams.set("blur", `${blurOptions.blur}`);
  }

  return `/_next/image?${searchParams.toString()}`;
};

name = "optimizaan"
compatibility_date = "2023-12-01"
main="src/index.ts"
workers_dev = false

routes = [
  { pattern = "www.flatkobo.com/_next/*", zone_name = "flatkobo.com" },
  { pattern = "www.flatkobo.com/images/*", zone_name = "flatkobo.com" },

  { pattern = "lp.flatkobo.com/events/kobosai-2023/img/*", zone_name = "flatkobo.com" },
  { pattern = "lp.flatkobo.com/_next/*", zone_name = "flatkobo.com" },
  { pattern = "lp.flatkobo.com/images/*", zone_name = "flatkobo.com" },
]

import { Hono } from "hono";

import { transformImageHandler as transformRawImageHandler } from "./optimize-images";
import { transformImageHandler as transformURLImageHandler } from "./optimize-images/with-url";


const app = new Hono<Env>({
  getPath: (req) => req.url.replace(/^https?:\/([^?]+).*$/, "$1"),
});

app.get("/www.flatkobo.com/_next/image", ...transformURLImageHandler);
app.get(
  "/www.flatkobo.com/_next/static/media/*.:ext{jpg|jpeg|webp|png|avif|gif}",
  ...transformRawImageHandler,
);
app.get("/www.flatkobo.com/images/*", ...transformRawImageHandler);

app.get("/lp.flatkobo.com/_next/image", ...transformURLImageHandler);
app.get(
  "/lp.flatkobo.com/_next/static/media/*.:ext{jpg|jpeg|webp|png|avif|gif}",
  ...transformRawImageHandler,
);
app.get("/lp.flatkobo.com/images/*", ...transformRawImageHandler);
app.get(
  "/lp.flatkobo.com/events/kobosai-2023/img/*",
  ...transformRawImageHandler,
);

app.get("*", (c) => fetch(c.req.raw));

export default app;