[新服务]Picgo-BackBlaze B2 S3-Cloudflare Worker隐藏桶名称

date

Nov 1, 2021

slug

Picgo-BackBlazeS3-Cloudflare

status

Published

summary

图床 BackBlaze 10G免费S3 利用CloudFlare免费无限流量

Summary

图床 BackBlaze B2 10G免费S3 利用CloudFlare免费无限流量

https://wlnxing.com/archives/49.html

https://blog.meow.page/archives/free-personal-image-hosting-with-backblaze-b2-and-cloudflare-workers/

历史关于picgo的文章

步骤

获得B2上面的bucket + appId + appKey

CloudFlare 自定义域名 + Worker来隐藏bucket名称

自定义图床域名 b2.your-own.domain

解决SSL带来的重定向太多问题

Worker Script

'use strict';
const b2Domain = 'b2.your-own.domain'; // 必须是上面设置的自定义域名
const b2Bucket = '使用前此处改为你的存储桶的名字'; // configure this as per instructions above
const b2UrlPath = `/file/${b2Bucket}/`;
addEventListener('fetch', event => {
    return event.respondWith(fileReq(event));
});

// define the file extensions we wish to add basic access control headers to
const corsFileTypes = ['png', 'jpg', 'gif', 'jpeg', 'webp'];

// backblaze returns some additional headers that are useful for debugging, but unnecessary in production. We can remove these to save some size
const removeHeaders = [
    'x-bz-content-sha1',
    'x-bz-file-id',
    'x-bz-file-name',
    'x-bz-info-src_last_modified_millis',
    'X-Bz-Upload-Timestamp',
    'Expires'
];
const expiration = 31536000; // override browser cache for images - 1 year

// define a function we can re-use to fix headers
const fixHeaders = function(url, status, headers){
    let newHdrs = new Headers(headers);
    // add basic cors headers for images
    if(corsFileTypes.includes(url.pathname.split('.').pop())){
        newHdrs.set('Access-Control-Allow-Origin', '*');
    }
    // override browser cache for files when 200
    if(status === 200){
        newHdrs.set('Cache-Control', "public, max-age=" + expiration);
    }else{
        // only cache other things for 5 minutes
        newHdrs.set('Cache-Control', 'public, max-age=300');
    }
    // set ETag for efficient caching where possible
    const ETag = newHdrs.get('x-bz-content-sha1') || newHdrs.get('x-bz-info-src_last_modified_millis') || newHdrs.get('x-bz-file-id');
    if(ETag){
        newHdrs.set('ETag', ETag);
    }
    // remove unnecessary headers
    removeHeaders.forEach(header => {
        newHdrs.delete(header);
    });
    return newHdrs;
};
async function fileReq(event){
    const cache = caches.default; // Cloudflare edge caching
    const url = new URL(event.request.url);
    if(url.host === b2Domain && !url.pathname.startsWith(b2UrlPath)){
        url.pathname = b2UrlPath + url.pathname;
    }
    let response = await cache.match(url); // try to find match for this request in the edge cache
    if(response){
        // use cache found on Cloudflare edge. Set X-Worker-Cache header for helpful debug
        let newHdrs = fixHeaders(url, response.status, response.headers);
        newHdrs.set('X-Worker-Cache', "true");
        return new Response(response.body, {
            status: response.status,
            statusText: response.statusText,
            headers: newHdrs
        });
    }
    // no cache, fetch image, apply Cloudflare lossless compression
    response = await fetch(url, {cf: {polish: "lossless"}});
    let newHdrs = fixHeaders(url, response.status, response.headers);

  if(response.status === 200){

    response = new Response(response.body, {
      status: response.status,
      statusText: response.statusText,
      headers: newHdrs
    });
  }else{
    response = new Response('File not found!', { status: 404 })
  }

    event.waitUntil(cache.put(url, response.clone()));
    return response;
}