1 files changed, 312 insertions, 0 deletions
diff --git a/node_modules/@cloudflare/kv-asset-handler/src/index.ts b/node_modules/@cloudflare/kv-asset-handler/src/index.ts
new file mode 100644
index 0000000..5a91b68
--- /dev/null
+++ b/node_modules/@cloudflare/kv-asset-handler/src/index.ts
@@ -0,0 +1,312 @@
+import * as mime from 'mime'
+import {
+  Options,
+  CacheControl,
+  MethodNotAllowedError,
+  NotFoundError,
+  InternalError,
+  AssetManifestType,
+} from './types'
+
+declare global {
+  var __STATIC_CONTENT: any, __STATIC_CONTENT_MANIFEST: string
+}
+
+const defaultCacheControl: CacheControl = {
+  browserTTL: null,
+  edgeTTL: 2 * 60 * 60 * 24, // 2 days
+  bypassCache: false, // do not bypass Cloudflare's cache
+}
+
+const parseStringAsObject = <T>(maybeString: string | T): T =>
+  typeof maybeString === 'string' ? (JSON.parse(maybeString) as T) : maybeString
+
+const getAssetFromKVDefaultOptions: Partial<Options> = {
+  ASSET_NAMESPACE: typeof __STATIC_CONTENT !== 'undefined' ? __STATIC_CONTENT : undefined,
+  ASSET_MANIFEST:
+    typeof __STATIC_CONTENT_MANIFEST !== 'undefined'
+      ? parseStringAsObject<AssetManifestType>(__STATIC_CONTENT_MANIFEST)
+      : {},
+  cacheControl: defaultCacheControl,
+  defaultMimeType: 'text/plain',
+  defaultDocument: 'index.html',
+  pathIsEncoded: false,
+}
+
+function assignOptions(options?: Partial<Options>): Options {
+  // Assign any missing options passed in to the default
+  // options.mapRequestToAsset is handled manually later
+  return <Options>Object.assign({}, getAssetFromKVDefaultOptions, options)
+}
+
+/**
+ * maps the path of incoming request to the request pathKey to look up
+ * in bucket and in cache
+ * e.g.  for a path '/' returns '/index.html' which serves
+ * the content of bucket/index.html
+ * @param {Request} request incoming request
+ */
+const mapRequestToAsset = (request: Request, options?: Partial<Options>) => {
+  options = assignOptions(options)
+
+  const parsedUrl = new URL(request.url)
+  let pathname = parsedUrl.pathname
+
+  if (pathname.endsWith('/')) {
+    // If path looks like a directory append options.defaultDocument
+    // e.g. If path is /about/ -> /about/index.html
+    pathname = pathname.concat(options.defaultDocument)
+  } else if (!mime.getType(pathname)) {
+    // If path doesn't look like valid content
+    //  e.g. /about.me ->  /about.me/index.html
+    pathname = pathname.concat('/' + options.defaultDocument)
+  }
+
+  parsedUrl.pathname = pathname
+  return new Request(parsedUrl.toString(), request)
+}
+
+/**
+ * maps the path of incoming request to /index.html if it evaluates to
+ * any HTML file.
+ * @param {Request} request incoming request
+ */
+function serveSinglePageApp(request: Request, options?: Partial<Options>): Request {
+  options = assignOptions(options)
+
+  // First apply the default handler, which already has logic to detect
+  // paths that should map to HTML files.
+  request = mapRequestToAsset(request, options)
+
+  const parsedUrl = new URL(request.url)
+
+  // Detect if the default handler decided to map to
+  // a HTML file in some specific directory.
+  if (parsedUrl.pathname.endsWith('.html')) {
+    // If expected HTML file was missing, just return the root index.html (or options.defaultDocument)
+    return new Request(`${parsedUrl.origin}/${options.defaultDocument}`, request)
+  } else {
+    // The default handler decided this is not an HTML page. It's probably
+    // an image, CSS, or JS file. Leave it as-is.
+    return request
+  }
+}
+
+/**
+ * takes the path of the incoming request, gathers the appropriate content from KV, and returns
+ * the response
+ *
+ * @param {FetchEvent} event the fetch event of the triggered request
+ * @param {{mapRequestToAsset: (string: Request) => Request, cacheControl: {bypassCache:boolean, edgeTTL: number, browserTTL:number}, ASSET_NAMESPACE: any, ASSET_MANIFEST:any}} [options] configurable options
+ * @param {CacheControl} [options.cacheControl] determine how to cache on Cloudflare and the browser
+ * @param {typeof(options.mapRequestToAsset)} [options.mapRequestToAsset]  maps the path of incoming request to the request pathKey to look up
+ * @param {Object | string} [options.ASSET_NAMESPACE] the binding to the namespace that script references
+ * @param {any} [options.ASSET_MANIFEST] the map of the key to cache and store in KV
+ * */
+
+type Evt = {
+  request: Request
+  waitUntil: (promise: Promise<any>) => void
+}
+
+const getAssetFromKV = async (event: Evt, options?: Partial<Options>): Promise<Response> => {
+  options = assignOptions(options)
+
+  const request = event.request
+  const ASSET_NAMESPACE = options.ASSET_NAMESPACE
+  const ASSET_MANIFEST = parseStringAsObject<AssetManifestType>(options.ASSET_MANIFEST)
+
+  if (typeof ASSET_NAMESPACE === 'undefined') {
+    throw new InternalError(`there is no KV namespace bound to the script`)
+  }
+
+  const rawPathKey = new URL(request.url).pathname.replace(/^\/+/, '') // strip any preceding /'s
+  let pathIsEncoded = options.pathIsEncoded
+  let requestKey
+  // if options.mapRequestToAsset is explicitly passed in, always use it and assume user has own intentions
+  // otherwise handle request as normal, with default mapRequestToAsset below
+  if (options.mapRequestToAsset) {
+    requestKey = options.mapRequestToAsset(request)
+  } else if (ASSET_MANIFEST[rawPathKey]) {
+    requestKey = request
+  } else if (ASSET_MANIFEST[decodeURIComponent(rawPathKey)]) {
+    pathIsEncoded = true
+    requestKey = request
+  } else {
+    const mappedRequest = mapRequestToAsset(request)
+    const mappedRawPathKey = new URL(mappedRequest.url).pathname.replace(/^\/+/, '')
+    if (ASSET_MANIFEST[decodeURIComponent(mappedRawPathKey)]) {
+      pathIsEncoded = true
+      requestKey = mappedRequest
+    } else {
+      // use default mapRequestToAsset
+      requestKey = mapRequestToAsset(request, options)
+    }
+  }
+
+  const SUPPORTED_METHODS = ['GET', 'HEAD']
+  if (!SUPPORTED_METHODS.includes(requestKey.method)) {
+    throw new MethodNotAllowedError(`${requestKey.method} is not a valid request method`)
+  }
+
+  const parsedUrl = new URL(requestKey.url)
+  const pathname = pathIsEncoded ? decodeURIComponent(parsedUrl.pathname) : parsedUrl.pathname // decode percentage encoded path only when necessary
+
+  // pathKey is the file path to look up in the manifest
+  let pathKey = pathname.replace(/^\/+/, '') // remove prepended /
+
+  // @ts-ignore
+  const cache = caches.default
+  let mimeType = mime.getType(pathKey) || options.defaultMimeType
+  if (mimeType.startsWith('text') || mimeType === 'application/javascript') {
+    mimeType += '; charset=utf-8'
+  }
+
+  let shouldEdgeCache = false // false if storing in KV by raw file path i.e. no hash
+  // check manifest for map from file path to hash
+  if (typeof ASSET_MANIFEST !== 'undefined') {
+    if (ASSET_MANIFEST[pathKey]) {
+      pathKey = ASSET_MANIFEST[pathKey]
+      // if path key is in asset manifest, we can assume it contains a content hash and can be cached
+      shouldEdgeCache = true
+    }
+  }
+
+  // TODO this excludes search params from cache, investigate ideal behavior
+  let cacheKey = new Request(`${parsedUrl.origin}/${pathKey}`, request)
+
+  // if argument passed in for cacheControl is a function then
+  // evaluate that function. otherwise return the Object passed in
+  // or default Object
+  const evalCacheOpts = (() => {
+    switch (typeof options.cacheControl) {
+      case 'function':
+        return options.cacheControl(request)
+      case 'object':
+        return options.cacheControl
+      default:
+        return defaultCacheControl
+    }
+  })()
+
+  // formats the etag depending on the response context. if the entityId
+  // is invalid, returns an empty string (instead of null) to prevent the
+  // the potentially disastrous scenario where the value of the Etag resp
+  // header is "null". Could be modified in future to base64 encode etc
+  const formatETag = (entityId: any = pathKey, validatorType: string = 'strong') => {
+    if (!entityId) {
+      return ''
+    }
+    switch (validatorType) {
+      case 'weak':
+        if (!entityId.startsWith('W/')) {
+          return `W/${entityId}`
+        }
+        return entityId
+      case 'strong':
+        if (entityId.startsWith(`W/"`)) {
+          entityId = entityId.replace('W/', '')
+        }
+        if (!entityId.endsWith(`"`)) {
+          entityId = `"${entityId}"`
+        }
+        return entityId
+      default:
+        return ''
+    }
+  }
+
+  options.cacheControl = Object.assign({}, defaultCacheControl, evalCacheOpts)
+
+  // override shouldEdgeCache if options say to bypassCache
+  if (
+    options.cacheControl.bypassCache ||
+    options.cacheControl.edgeTTL === null ||
+    request.method == 'HEAD'
+  ) {
+    shouldEdgeCache = false
+  }
+  // only set max-age if explicitly passed in a number as an arg
+  const shouldSetBrowserCache = typeof options.cacheControl.browserTTL === 'number'
+
+  let response = null
+  if (shouldEdgeCache) {
+    response = await cache.match(cacheKey)
+  }
+
+  if (response) {
+    if (response.status > 300 && response.status < 400) {
+      if (response.body && 'cancel' in Object.getPrototypeOf(response.body)) {
+        // Body exists and environment supports readable streams
+        response.body.cancel()
+      } else {
+        // Environment doesnt support readable streams, or null repsonse body. Nothing to do
+      }
+      response = new Response(null, response)
+    } else {
+      // fixes #165
+      let opts = {
+        headers: new Headers(response.headers),
+        status: 0,
+        statusText: '',
+      }
+
+      opts.headers.set('cf-cache-status', 'HIT')
+
+      if (response.status) {
+        opts.status = response.status
+        opts.statusText = response.statusText
+      } else if (opts.headers.has('Content-Range')) {
+        opts.status = 206
+        opts.statusText = 'Partial Content'
+      } else {
+        opts.status = 200
+        opts.statusText = 'OK'
+      }
+      response = new Response(response.body, opts)
+    }
+  } else {
+    const body = await ASSET_NAMESPACE.get(pathKey, 'arrayBuffer')
+    if (body === null) {
+      throw new NotFoundError(`could not find ${pathKey} in your content namespace`)
+    }
+    response = new Response(body)
+
+    if (shouldEdgeCache) {
+      response.headers.set('Accept-Ranges', 'bytes')
+      response.headers.set('Content-Length', body.length)
+      // set etag before cache insertion
+      if (!response.headers.has('etag')) {
+        response.headers.set('etag', formatETag(pathKey, 'strong'))
+      }
+      // determine Cloudflare cache behavior
+      response.headers.set('Cache-Control', `max-age=${options.cacheControl.edgeTTL}`)
+      event.waitUntil(cache.put(cacheKey, response.clone()))
+      response.headers.set('CF-Cache-Status', 'MISS')
+    }
+  }
+  response.headers.set('Content-Type', mimeType)
+
+  if (response.status === 304) {
+    let etag = formatETag(response.headers.get('etag'), 'strong')
+    let ifNoneMatch = cacheKey.headers.get('if-none-match')
+    let proxyCacheStatus = response.headers.get('CF-Cache-Status')
+    if (etag) {
+      if (ifNoneMatch && ifNoneMatch === etag && proxyCacheStatus === 'MISS') {
+        response.headers.set('CF-Cache-Status', 'EXPIRED')
+      } else {
+        response.headers.set('CF-Cache-Status', 'REVALIDATED')
+      }
+      response.headers.set('etag', formatETag(etag, 'weak'))
+    }
+  }
+  if (shouldSetBrowserCache) {
+    response.headers.set('Cache-Control', `max-age=${options.cacheControl.browserTTL}`)
+  } else {
+    response.headers.delete('Cache-Control')
+  }
+  return response
+}
+
+export { getAssetFromKV, mapRequestToAsset, serveSinglePageApp }
+export { Options, CacheControl, MethodNotAllowedError, NotFoundError, InternalError }