$

node_modules/make-fetch-happen/lib/cache/entry.js

@@ -0,0 +1,444 @@
+const { Request, Response } = require('minipass-fetch')
+const Minipass = require('minipass')
+const MinipassFlush = require('minipass-flush')
+const cacache = require('cacache')
+const url = require('url')
+
+const CachingMinipassPipeline = require('../pipeline.js')
+const CachePolicy = require('./policy.js')
+const cacheKey = require('./key.js')
+const remote = require('../remote.js')
+
+const hasOwnProperty = (obj, prop) => Object.prototype.hasOwnProperty.call(obj, prop)
+
+// allow list for request headers that will be written to the cache index
+// note: we will also store any request headers
+// that are named in a response's vary header
+const KEEP_REQUEST_HEADERS = [
+  'accept-charset',
+  'accept-encoding',
+  'accept-language',
+  'accept',
+  'cache-control',
+]
+
+// allow list for response headers that will be written to the cache index
+// note: we must not store the real response's age header, or when we load
+// a cache policy based on the metadata it will think the cached response
+// is always stale
+const KEEP_RESPONSE_HEADERS = [
+  'cache-control',
+  'content-encoding',
+  'content-language',
+  'content-type',
+  'date',
+  'etag',
+  'expires',
+  'last-modified',
+  'link',
+  'location',
+  'pragma',
+  'vary',
+]
+
+// return an object containing all metadata to be written to the index
+const getMetadata = (request, response, options) => {
+  const metadata = {
+    time: Date.now(),
+    url: request.url,
+    reqHeaders: {},
+    resHeaders: {},
+
+    // options on which we must match the request and vary the response
+    options: {
+      compress: options.compress != null ? options.compress : request.compress,
+    },
+  }
+
+  // only save the status if it's not a 200 or 304
+  if (response.status !== 200 && response.status !== 304) {
+    metadata.status = response.status
+  }
+
+  for (const name of KEEP_REQUEST_HEADERS) {
+    if (request.headers.has(name)) {
+      metadata.reqHeaders[name] = request.headers.get(name)
+    }
+  }
+
+  // if the request's host header differs from the host in the url
+  // we need to keep it, otherwise it's just noise and we ignore it
+  const host = request.headers.get('host')
+  const parsedUrl = new url.URL(request.url)
+  if (host && parsedUrl.host !== host) {
+    metadata.reqHeaders.host = host
+  }
+
+  // if the response has a vary header, make sure
+  // we store the relevant request headers too
+  if (response.headers.has('vary')) {
+    const vary = response.headers.get('vary')
+    // a vary of "*" means every header causes a different response.
+    // in that scenario, we do not include any additional headers
+    // as the freshness check will always fail anyway and we don't
+    // want to bloat the cache indexes
+    if (vary !== '*') {
+      // copy any other request headers that will vary the response
+      const varyHeaders = vary.trim().toLowerCase().split(/\s*,\s*/)
+      for (const name of varyHeaders) {
+        if (request.headers.has(name)) {
+          metadata.reqHeaders[name] = request.headers.get(name)
+        }
+      }
+    }
+  }
+
+  for (const name of KEEP_RESPONSE_HEADERS) {
+    if (response.headers.has(name)) {
+      metadata.resHeaders[name] = response.headers.get(name)
+    }
+  }
+
+  return metadata
+}
+
+// symbols used to hide objects that may be lazily evaluated in a getter
+const _request = Symbol('request')
+const _response = Symbol('response')
+const _policy = Symbol('policy')
+
+class CacheEntry {
+  constructor ({ entry, request, response, options }) {
+    if (entry) {
+      this.key = entry.key
+      this.entry = entry
+      // previous versions of this module didn't write an explicit timestamp in
+      // the metadata, so fall back to the entry's timestamp. we can't use the
+      // entry timestamp to determine staleness because cacache will update it
+      // when it verifies its data
+      this.entry.metadata.time = this.entry.metadata.time || this.entry.time
+    } else {
+      this.key = cacheKey(request)
+    }
+
+    this.options = options
+
+    // these properties are behind getters that lazily evaluate
+    this[_request] = request
+    this[_response] = response
+    this[_policy] = null
+  }
+
+  // returns a CacheEntry instance that satisfies the given request
+  // or undefined if no existing entry satisfies
+  static async find (request, options) {
+    try {
+      // compacts the index and returns an array of unique entries
+      var matches = await cacache.index.compact(options.cachePath, cacheKey(request), (A, B) => {
+        const entryA = new CacheEntry({ entry: A, options })
+        const entryB = new CacheEntry({ entry: B, options })
+        return entryA.policy.satisfies(entryB.request)
+      }, {
+        validateEntry: (entry) => {
+          // clean out entries with a buggy content-encoding value
+          if (entry.metadata &&
+              entry.metadata.resHeaders &&
+              entry.metadata.resHeaders['content-encoding'] === null) {
+            return false
+          }
+
+          // if an integrity is null, it needs to have a status specified
+          if (entry.integrity === null) {
+            return !!(entry.metadata && entry.metadata.status)
+          }
+
+          return true
+        },
+      })
+    } catch (err) {
+      // if the compact request fails, ignore the error and return
+      return
+    }
+
+    // a cache mode of 'reload' means to behave as though we have no cache
+    // on the way to the network. return undefined to allow cacheFetch to
+    // create a brand new request no matter what.
+    if (options.cache === 'reload') {
+      return
+    }
+
+    // find the specific entry that satisfies the request
+    let match
+    for (const entry of matches) {
+      const _entry = new CacheEntry({
+        entry,
+        options,
+      })
+
+      if (_entry.policy.satisfies(request)) {
+        match = _entry
+        break
+      }
+    }
+
+    return match
+  }
+
+  // if the user made a PUT/POST/PATCH then we invalidate our
+  // cache for the same url by deleting the index entirely
+  static async invalidate (request, options) {
+    const key = cacheKey(request)
+    try {
+      await cacache.rm.entry(options.cachePath, key, { removeFully: true })
+    } catch (err) {
+      // ignore errors
+    }
+  }
+
+  get request () {
+    if (!this[_request]) {
+      this[_request] = new Request(this.entry.metadata.url, {
+        method: 'GET',
+        headers: this.entry.metadata.reqHeaders,
+        ...this.entry.metadata.options,
+      })
+    }
+
+    return this[_request]
+  }
+
+  get response () {
+    if (!this[_response]) {
+      this[_response] = new Response(null, {
+        url: this.entry.metadata.url,
+        counter: this.options.counter,
+        status: this.entry.metadata.status || 200,
+        headers: {
+          ...this.entry.metadata.resHeaders,
+          'content-length': this.entry.size,
+        },
+      })
+    }
+
+    return this[_response]
+  }
+
+  get policy () {
+    if (!this[_policy]) {
+      this[_policy] = new CachePolicy({
+        entry: this.entry,
+        request: this.request,
+        response: this.response,
+        options: this.options,
+      })
+    }
+
+    return this[_policy]
+  }
+
+  // wraps the response in a pipeline that stores the data
+  // in the cache while the user consumes it
+  async store (status) {
+    // if we got a status other than 200, 301, or 308,
+    // or the CachePolicy forbid storage, append the
+    // cache status header and return it untouched
+    if (
+      this.request.method !== 'GET' ||
+      ![200, 301, 308].includes(this.response.status) ||
+      !this.policy.storable()
+    ) {
+      this.response.headers.set('x-local-cache-status', 'skip')
+      return this.response
+    }
+
+    const size = this.response.headers.get('content-length')
+    const cacheOpts = {
+      algorithms: this.options.algorithms,
+      metadata: getMetadata(this.request, this.response, this.options),
+      size,
+      integrity: this.options.integrity,
+      integrityEmitter: this.response.body.hasIntegrityEmitter && this.response.body,
+    }
+
+    let body = null
+    // we only set a body if the status is a 200, redirects are
+    // stored as metadata only
+    if (this.response.status === 200) {
+      let cacheWriteResolve, cacheWriteReject
+      const cacheWritePromise = new Promise((resolve, reject) => {
+        cacheWriteResolve = resolve
+        cacheWriteReject = reject
+      })
+
+      body = new CachingMinipassPipeline({ events: ['integrity', 'size'] }, new MinipassFlush({
+        flush () {
+          return cacheWritePromise
+        },
+      }))
+      // this is always true since if we aren't reusing the one from the remote fetch, we
+      // are using the one from cacache
+      body.hasIntegrityEmitter = true
+
+      const onResume = () => {
+        const tee = new Minipass()
+        const cacheStream = cacache.put.stream(this.options.cachePath, this.key, cacheOpts)
+        // re-emit the integrity and size events on our new response body so they can be reused
+        cacheStream.on('integrity', i => body.emit('integrity', i))
+        cacheStream.on('size', s => body.emit('size', s))
+        // stick a flag on here so downstream users will know if they can expect integrity events
+        tee.pipe(cacheStream)
+        // TODO if the cache write fails, log a warning but return the response anyway
+        // eslint-disable-next-line promise/catch-or-return
+        cacheStream.promise().then(cacheWriteResolve, cacheWriteReject)
+        body.unshift(tee)
+        body.unshift(this.response.body)
+      }
+
+      body.once('resume', onResume)
+      body.once('end', () => body.removeListener('resume', onResume))
+    } else {
+      await cacache.index.insert(this.options.cachePath, this.key, null, cacheOpts)
+    }
+
+    // note: we do not set the x-local-cache-hash header because we do not know
+    // the hash value until after the write to the cache completes, which doesn't
+    // happen until after the response has been sent and it's too late to write
+    // the header anyway
+    this.response.headers.set('x-local-cache', encodeURIComponent(this.options.cachePath))
+    this.response.headers.set('x-local-cache-key', encodeURIComponent(this.key))
+    this.response.headers.set('x-local-cache-mode', 'stream')
+    this.response.headers.set('x-local-cache-status', status)
+    this.response.headers.set('x-local-cache-time', new Date().toISOString())
+    const newResponse = new Response(body, {
+      url: this.response.url,
+      status: this.response.status,
+      headers: this.response.headers,
+      counter: this.options.counter,
+    })
+    return newResponse
+  }
+
+  // use the cached data to create a response and return it
+  async respond (method, options, status) {
+    let response
+    if (method === 'HEAD' || [301, 308].includes(this.response.status)) {
+      // if the request is a HEAD, or the response is a redirect,
+      // then the metadata in the entry already includes everything
+      // we need to build a response
+      response = this.response
+    } else {
+      // we're responding with a full cached response, so create a body
+      // that reads from cacache and attach it to a new Response
+      const body = new Minipass()
+      const headers = { ...this.policy.responseHeaders() }
+      const onResume = () => {
+        const cacheStream = cacache.get.stream.byDigest(
+          this.options.cachePath, this.entry.integrity, { memoize: this.options.memoize }
+        )
+        cacheStream.on('error', async (err) => {
+          cacheStream.pause()
+          if (err.code === 'EINTEGRITY') {
+            await cacache.rm.content(
+              this.options.cachePath, this.entry.integrity, { memoize: this.options.memoize }
+            )
+          }
+          if (err.code === 'ENOENT' || err.code === 'EINTEGRITY') {
+            await CacheEntry.invalidate(this.request, this.options)
+          }
+          body.emit('error', err)
+          cacheStream.resume()
+        })
+        // emit the integrity and size events based on our metadata so we're consistent
+        body.emit('integrity', this.entry.integrity)
+        body.emit('size', Number(headers['content-length']))
+        cacheStream.pipe(body)
+      }
+
+      body.once('resume', onResume)
+      body.once('end', () => body.removeListener('resume', onResume))
+      response = new Response(body, {
+        url: this.entry.metadata.url,
+        counter: options.counter,
+        status: 200,
+        headers,
+      })
+    }
+
+    response.headers.set('x-local-cache', encodeURIComponent(this.options.cachePath))
+    response.headers.set('x-local-cache-hash', encodeURIComponent(this.entry.integrity))
+    response.headers.set('x-local-cache-key', encodeURIComponent(this.key))
+    response.headers.set('x-local-cache-mode', 'stream')
+    response.headers.set('x-local-cache-status', status)
+    response.headers.set('x-local-cache-time', new Date(this.entry.metadata.time).toUTCString())
+    return response
+  }
+
+  // use the provided request along with this cache entry to
+  // revalidate the stored response. returns a response, either
+  // from the cache or from the update
+  async revalidate (request, options) {
+    const revalidateRequest = new Request(request, {
+      headers: this.policy.revalidationHeaders(request),
+    })
+
+    try {
+      // NOTE: be sure to remove the headers property from the
+      // user supplied options, since we have already defined
+      // them on the new request object. if they're still in the
+      // options then those will overwrite the ones from the policy
+      var response = await remote(revalidateRequest, {
+        ...options,
+        headers: undefined,
+      })
+    } catch (err) {
+      // if the network fetch fails, return the stale
+      // cached response unless it has a cache-control
+      // of 'must-revalidate'
+      if (!this.policy.mustRevalidate) {
+        return this.respond(request.method, options, 'stale')
+      }
+
+      throw err
+    }
+
+    if (this.policy.revalidated(revalidateRequest, response)) {
+      // we got a 304, write a new index to the cache and respond from cache
+      const metadata = getMetadata(request, response, options)
+      // 304 responses do not include headers that are specific to the response data
+      // since they do not include a body, so we copy values for headers that were
+      // in the old cache entry to the new one, if the new metadata does not already
+      // include that header
+      for (const name of KEEP_RESPONSE_HEADERS) {
+        if (
+          !hasOwnProperty(metadata.resHeaders, name) &&
+          hasOwnProperty(this.entry.metadata.resHeaders, name)
+        ) {
+          metadata.resHeaders[name] = this.entry.metadata.resHeaders[name]
+        }
+      }
+
+      try {
+        await cacache.index.insert(options.cachePath, this.key, this.entry.integrity, {
+          size: this.entry.size,
+          metadata,
+        })
+      } catch (err) {
+        // if updating the cache index fails, we ignore it and
+        // respond anyway
+      }
+      return this.respond(request.method, options, 'revalidated')
+    }
+
+    // if we got a modified response, create a new entry based on it
+    const newEntry = new CacheEntry({
+      request,
+      response,
+      options,
+    })
+
+    // respond with the new entry while writing it to the cache
+    return newEntry.store('updated')
+  }
+}
+
+module.exports = CacheEntry

node_modules/make-fetch-happen/lib/cache/errors.js

@@ -0,0 +1,11 @@
+class NotCachedError extends Error {
+  constructor (url) {
+    /* eslint-disable-next-line max-len */
+    super(`request to ${url} failed: cache mode is 'only-if-cached' but no cached response is available.`)
+    this.code = 'ENOTCACHED'
+  }
+}
+
+module.exports = {
+  NotCachedError,
+}

node_modules/make-fetch-happen/lib/cache/index.js

@@ -0,0 +1,49 @@
+const { NotCachedError } = require('./errors.js')
+const CacheEntry = require('./entry.js')
+const remote = require('../remote.js')
+
+// do whatever is necessary to get a Response and return it
+const cacheFetch = async (request, options) => {
+  // try to find a cached entry that satisfies this request
+  const entry = await CacheEntry.find(request, options)
+  if (!entry) {
+    // no cached result, if the cache mode is 'only-if-cached' that's a failure
+    if (options.cache === 'only-if-cached') {
+      throw new NotCachedError(request.url)
+    }
+
+    // otherwise, we make a request, store it and return it
+    const response = await remote(request, options)
+    const newEntry = new CacheEntry({ request, response, options })
+    return newEntry.store('miss')
+  }
+
+  // we have a cached response that satisfies this request, however if the cache
+  // mode is 'no-cache' then we send the revalidation request no matter what
+  if (options.cache === 'no-cache') {
+    return entry.revalidate(request, options)
+  }
+
+  // if the cached entry is not stale, or if the cache mode is 'force-cache' or
+  // 'only-if-cached' we can respond with the cached entry. set the status
+  // based on the result of needsRevalidation and respond
+  const _needsRevalidation = entry.policy.needsRevalidation(request)
+  if (options.cache === 'force-cache' ||
+      options.cache === 'only-if-cached' ||
+      !_needsRevalidation) {
+    return entry.respond(request.method, options, _needsRevalidation ? 'stale' : 'hit')
+  }
+
+  // if we got here, the cache entry is stale so revalidate it
+  return entry.revalidate(request, options)
+}
+
+cacheFetch.invalidate = async (request, options) => {
+  if (!options.cachePath) {
+    return
+  }
+
+  return CacheEntry.invalidate(request, options)
+}
+
+module.exports = cacheFetch

node_modules/make-fetch-happen/lib/cache/key.js

@@ -0,0 +1,17 @@
+const { URL, format } = require('url')
+
+// options passed to url.format() when generating a key
+const formatOptions = {
+  auth: false,
+  fragment: false,
+  search: true,
+  unicode: false,
+}
+
+// returns a string to be used as the cache key for the Request
+const cacheKey = (request) => {
+  const parsed = new URL(request.url)
+  return `make-fetch-happen:request-cache:${format(parsed, formatOptions)}`
+}
+
+module.exports = cacheKey

node_modules/make-fetch-happen/lib/cache/policy.js

@@ -0,0 +1,161 @@
+const CacheSemantics = require('http-cache-semantics')
+const Negotiator = require('negotiator')
+const ssri = require('ssri')
+
+// options passed to http-cache-semantics constructor
+const policyOptions = {
+  shared: false,
+  ignoreCargoCult: true,
+}
+
+// a fake empty response, used when only testing the
+// request for storability
+const emptyResponse = { status: 200, headers: {} }
+
+// returns a plain object representation of the Request
+const requestObject = (request) => {
+  const _obj = {
+    method: request.method,
+    url: request.url,
+    headers: {},
+    compress: request.compress,
+  }
+
+  request.headers.forEach((value, key) => {
+    _obj.headers[key] = value
+  })
+
+  return _obj
+}
+
+// returns a plain object representation of the Response
+const responseObject = (response) => {
+  const _obj = {
+    status: response.status,
+    headers: {},
+  }
+
+  response.headers.forEach((value, key) => {
+    _obj.headers[key] = value
+  })
+
+  return _obj
+}
+
+class CachePolicy {
+  constructor ({ entry, request, response, options }) {
+    this.entry = entry
+    this.request = requestObject(request)
+    this.response = responseObject(response)
+    this.options = options
+    this.policy = new CacheSemantics(this.request, this.response, policyOptions)
+
+    if (this.entry) {
+      // if we have an entry, copy the timestamp to the _responseTime
+      // this is necessary because the CacheSemantics constructor forces
+      // the value to Date.now() which means a policy created from a
+      // cache entry is likely to always identify itself as stale
+      this.policy._responseTime = this.entry.metadata.time
+    }
+  }
+
+  // static method to quickly determine if a request alone is storable
+  static storable (request, options) {
+    // no cachePath means no caching
+    if (!options.cachePath) {
+      return false
+    }
+
+    // user explicitly asked not to cache
+    if (options.cache === 'no-store') {
+      return false
+    }
+
+    // we only cache GET and HEAD requests
+    if (!['GET', 'HEAD'].includes(request.method)) {
+      return false
+    }
+
+    // otherwise, let http-cache-semantics make the decision
+    // based on the request's headers
+    const policy = new CacheSemantics(requestObject(request), emptyResponse, policyOptions)
+    return policy.storable()
+  }
+
+  // returns true if the policy satisfies the request
+  satisfies (request) {
+    const _req = requestObject(request)
+    if (this.request.headers.host !== _req.headers.host) {
+      return false
+    }
+
+    if (this.request.compress !== _req.compress) {
+      return false
+    }
+
+    const negotiatorA = new Negotiator(this.request)
+    const negotiatorB = new Negotiator(_req)
+
+    if (JSON.stringify(negotiatorA.mediaTypes()) !== JSON.stringify(negotiatorB.mediaTypes())) {
+      return false
+    }
+
+    if (JSON.stringify(negotiatorA.languages()) !== JSON.stringify(negotiatorB.languages())) {
+      return false
+    }
+
+    if (JSON.stringify(negotiatorA.encodings()) !== JSON.stringify(negotiatorB.encodings())) {
+      return false
+    }
+
+    if (this.options.integrity) {
+      return ssri.parse(this.options.integrity).match(this.entry.integrity)
+    }
+
+    return true
+  }
+
+  // returns true if the request and response allow caching
+  storable () {
+    return this.policy.storable()
+  }
+
+  // NOTE: this is a hack to avoid parsing the cache-control
+  // header ourselves, it returns true if the response's
+  // cache-control contains must-revalidate
+  get mustRevalidate () {
+    return !!this.policy._rescc['must-revalidate']
+  }
+
+  // returns true if the cached response requires revalidation
+  // for the given request
+  needsRevalidation (request) {
+    const _req = requestObject(request)
+    // force method to GET because we only cache GETs
+    // but can serve a HEAD from a cached GET
+    _req.method = 'GET'
+    return !this.policy.satisfiesWithoutRevalidation(_req)
+  }
+
+  responseHeaders () {
+    return this.policy.responseHeaders()
+  }
+
+  // returns a new object containing the appropriate headers
+  // to send a revalidation request
+  revalidationHeaders (request) {
+    const _req = requestObject(request)
+    return this.policy.revalidationHeaders(_req)
+  }
+
+  // returns true if the request/response was revalidated
+  // successfully. returns false if a new response was received
+  revalidated (request, response) {
+    const _req = requestObject(request)
+    const _res = responseObject(response)
+    const policy = this.policy.revalidatedPolicy(_req, _res)
+    return !policy.modified
+  }
+}
+
+module.exports = CachePolicy