diff options
Diffstat (limited to 'deps/npm/node_modules/pacote/node_modules/make-fetch-happen/node_modules/http-cache-semantics/index.js')
| -rw-r--r-- | deps/npm/node_modules/pacote/node_modules/make-fetch-happen/node_modules/http-cache-semantics/index.js | 497 |
1 files changed, 0 insertions, 497 deletions
diff --git a/deps/npm/node_modules/pacote/node_modules/make-fetch-happen/node_modules/http-cache-semantics/index.js b/deps/npm/node_modules/pacote/node_modules/make-fetch-happen/node_modules/http-cache-semantics/index.js deleted file mode 100644 index 8a5bcab597..0000000000 --- a/deps/npm/node_modules/pacote/node_modules/make-fetch-happen/node_modules/http-cache-semantics/index.js +++ /dev/null @@ -1,497 +0,0 @@ -'use strict'; -// rfc7231 6.1 -const statusCodeCacheableByDefault = [200, 203, 204, 206, 300, 301, 404, 405, 410, 414, 501]; - -// This implementation does not understand partial responses (206) -const understoodStatuses = [200, 203, 204, 300, 301, 302, 303, 307, 308, 404, 405, 410, 414, 501]; - -const hopByHopHeaders = {'connection':true, 'keep-alive':true, 'proxy-authenticate':true, 'proxy-authorization':true, 'te':true, 'trailer':true, 'transfer-encoding':true, 'upgrade':true}; -const excludedFromRevalidationUpdate = { - // Since the old body is reused, it doesn't make sense to change properties of the body - 'content-length': true, 'content-encoding': true, 'transfer-encoding': true, - 'content-range': true, -}; - -function parseCacheControl(header) { - const cc = {}; - if (!header) return cc; - - // TODO: When there is more than one value present for a given directive (e.g., two Expires header fields, multiple Cache-Control: max-age directives), - // the directive's value is considered invalid. Caches are encouraged to consider responses that have invalid freshness information to be stale - const parts = header.trim().split(/\s*,\s*/); // TODO: lame parsing - for(const part of parts) { - const [k,v] = part.split(/\s*=\s*/, 2); - cc[k] = (v === undefined) ? true : v.replace(/^"|"$/g, ''); // TODO: lame unquoting - } - - return cc; -} - -function formatCacheControl(cc) { - let parts = []; - for(const k in cc) { - const v = cc[k]; - parts.push(v === true ? k : k + '=' + v); - } - if (!parts.length) { - return undefined; - } - return parts.join(', '); -} - -module.exports = class CachePolicy { - constructor(req, res, {shared, cacheHeuristic, immutableMinTimeToLive, ignoreCargoCult, _fromObject} = {}) { - if (_fromObject) { - this._fromObject(_fromObject); - return; - } - - if (!res || !res.headers) { - throw Error("Response headers missing"); - } - this._assertRequestHasHeaders(req); - - this._responseTime = this.now(); - this._isShared = shared !== false; - this._cacheHeuristic = undefined !== cacheHeuristic ? cacheHeuristic : 0.1; // 10% matches IE - this._immutableMinTtl = undefined !== immutableMinTimeToLive ? immutableMinTimeToLive : 24*3600*1000; - - this._status = 'status' in res ? res.status : 200; - this._resHeaders = res.headers; - this._rescc = parseCacheControl(res.headers['cache-control']); - this._method = 'method' in req ? req.method : 'GET'; - this._url = req.url; - this._host = req.headers.host; - this._noAuthorization = !req.headers.authorization; - this._reqHeaders = res.headers.vary ? req.headers : null; // Don't keep all request headers if they won't be used - this._reqcc = parseCacheControl(req.headers['cache-control']); - - // Assume that if someone uses legacy, non-standard uncecessary options they don't understand caching, - // so there's no point stricly adhering to the blindly copy&pasted directives. - if (ignoreCargoCult && "pre-check" in this._rescc && "post-check" in this._rescc) { - delete this._rescc['pre-check']; - delete this._rescc['post-check']; - delete this._rescc['no-cache']; - delete this._rescc['no-store']; - delete this._rescc['must-revalidate']; - this._resHeaders = Object.assign({}, this._resHeaders, {'cache-control': formatCacheControl(this._rescc)}); - delete this._resHeaders.expires; - delete this._resHeaders.pragma; - } - - // When the Cache-Control header field is not present in a request, caches MUST consider the no-cache request pragma-directive - // as having the same effect as if "Cache-Control: no-cache" were present (see Section 5.2.1). - if (!res.headers['cache-control'] && /no-cache/.test(res.headers.pragma)) { - this._rescc['no-cache'] = true; - } - } - - now() { - return Date.now(); - } - - storable() { - // The "no-store" request directive indicates that a cache MUST NOT store any part of either this request or any response to it. - return !!(!this._reqcc['no-store'] && - // A cache MUST NOT store a response to any request, unless: - // The request method is understood by the cache and defined as being cacheable, and - ('GET' === this._method || 'HEAD' === this._method || ('POST' === this._method && this._hasExplicitExpiration())) && - // the response status code is understood by the cache, and - understoodStatuses.indexOf(this._status) !== -1 && - // the "no-store" cache directive does not appear in request or response header fields, and - !this._rescc['no-store'] && - // the "private" response directive does not appear in the response, if the cache is shared, and - (!this._isShared || !this._rescc.private) && - // the Authorization header field does not appear in the request, if the cache is shared, - (!this._isShared || this._noAuthorization || this._allowsStoringAuthenticated()) && - // the response either: - ( - // contains an Expires header field, or - this._resHeaders.expires || - // contains a max-age response directive, or - // contains a s-maxage response directive and the cache is shared, or - // contains a public response directive. - this._rescc.public || this._rescc['max-age'] || this._rescc['s-maxage'] || - // has a status code that is defined as cacheable by default - statusCodeCacheableByDefault.indexOf(this._status) !== -1 - )); - } - - _hasExplicitExpiration() { - // 4.2.1 Calculating Freshness Lifetime - return (this._isShared && this._rescc['s-maxage']) || - this._rescc['max-age'] || - this._resHeaders.expires; - } - - _assertRequestHasHeaders(req) { - if (!req || !req.headers) { - throw Error("Request headers missing"); - } - } - - satisfiesWithoutRevalidation(req) { - this._assertRequestHasHeaders(req); - - // When presented with a request, a cache MUST NOT reuse a stored response, unless: - // the presented request does not contain the no-cache pragma (Section 5.4), nor the no-cache cache directive, - // unless the stored response is successfully validated (Section 4.3), and - const requestCC = parseCacheControl(req.headers['cache-control']); - if (requestCC['no-cache'] || /no-cache/.test(req.headers.pragma)) { - return false; - } - - if (requestCC['max-age'] && this.age() > requestCC['max-age']) { - return false; - } - - if (requestCC['min-fresh'] && this.timeToLive() < 1000*requestCC['min-fresh']) { - return false; - } - - // the stored response is either: - // fresh, or allowed to be served stale - if (this.stale()) { - const allowsStale = requestCC['max-stale'] && !this._rescc['must-revalidate'] && (true === requestCC['max-stale'] || requestCC['max-stale'] > this.age() - this.maxAge()); - if (!allowsStale) { - return false; - } - } - - return this._requestMatches(req, false); - } - - _requestMatches(req, allowHeadMethod) { - // The presented effective request URI and that of the stored response match, and - return (!this._url || this._url === req.url) && - (this._host === req.headers.host) && - // the request method associated with the stored response allows it to be used for the presented request, and - (!req.method || this._method === req.method || (allowHeadMethod && 'HEAD' === req.method)) && - // selecting header fields nominated by the stored response (if any) match those presented, and - this._varyMatches(req); - } - - _allowsStoringAuthenticated() { - // following Cache-Control response directives (Section 5.2.2) have such an effect: must-revalidate, public, and s-maxage. - return this._rescc['must-revalidate'] || this._rescc.public || this._rescc['s-maxage']; - } - - _varyMatches(req) { - if (!this._resHeaders.vary) { - return true; - } - - // A Vary header field-value of "*" always fails to match - if (this._resHeaders.vary === '*') { - return false; - } - - const fields = this._resHeaders.vary.trim().toLowerCase().split(/\s*,\s*/); - for(const name of fields) { - if (req.headers[name] !== this._reqHeaders[name]) return false; - } - return true; - } - - _copyWithoutHopByHopHeaders(inHeaders) { - const headers = {}; - for(const name in inHeaders) { - if (hopByHopHeaders[name]) continue; - headers[name] = inHeaders[name]; - } - // 9.1. Connection - if (inHeaders.connection) { - const tokens = inHeaders.connection.trim().split(/\s*,\s*/); - for(const name of tokens) { - delete headers[name]; - } - } - if (headers.warning) { - const warnings = headers.warning.split(/,/).filter(warning => { - return !/^\s*1[0-9][0-9]/.test(warning); - }); - if (!warnings.length) { - delete headers.warning; - } else { - headers.warning = warnings.join(',').trim(); - } - } - return headers; - } - - responseHeaders() { - const headers = this._copyWithoutHopByHopHeaders(this._resHeaders); - const age = this.age(); - - // A cache SHOULD generate 113 warning if it heuristically chose a freshness - // lifetime greater than 24 hours and the response's age is greater than 24 hours. - if (age > 3600*24 && !this._hasExplicitExpiration() && this.maxAge() > 3600*24) { - headers.warning = (headers.warning ? `${headers.warning}, ` : '') + '113 - "rfc7234 5.5.4"'; - } - headers.age = `${Math.round(age)}`; - return headers; - } - - /** - * Value of the Date response header or current time if Date was demed invalid - * @return timestamp - */ - date() { - const dateValue = Date.parse(this._resHeaders.date) - const maxClockDrift = 8*3600*1000; - if (Number.isNaN(dateValue) || dateValue < this._responseTime-maxClockDrift || dateValue > this._responseTime+maxClockDrift) { - return this._responseTime; - } - return dateValue; - } - - /** - * Value of the Age header, in seconds, updated for the current time. - * May be fractional. - * - * @return Number - */ - age() { - let age = Math.max(0, (this._responseTime - this.date())/1000); - if (this._resHeaders.age) { - let ageValue = this._ageValue(); - if (ageValue > age) age = ageValue; - } - - const residentTime = (this.now() - this._responseTime)/1000; - return age + residentTime; - } - - _ageValue() { - const ageValue = parseInt(this._resHeaders.age); - return isFinite(ageValue) ? ageValue : 0; - } - - /** - * Value of applicable max-age (or heuristic equivalent) in seconds. This counts since response's `Date`. - * - * For an up-to-date value, see `timeToLive()`. - * - * @return Number - */ - maxAge() { - if (!this.storable() || this._rescc['no-cache']) { - return 0; - } - - // Shared responses with cookies are cacheable according to the RFC, but IMHO it'd be unwise to do so by default - // so this implementation requires explicit opt-in via public header - if (this._isShared && (this._resHeaders['set-cookie'] && !this._rescc.public && !this._rescc.immutable)) { - return 0; - } - - if (this._resHeaders.vary === '*') { - return 0; - } - - if (this._isShared) { - if (this._rescc['proxy-revalidate']) { - return 0; - } - // if a response includes the s-maxage directive, a shared cache recipient MUST ignore the Expires field. - if (this._rescc['s-maxage']) { - return parseInt(this._rescc['s-maxage'], 10); - } - } - - // If a response includes a Cache-Control field with the max-age directive, a recipient MUST ignore the Expires field. - if (this._rescc['max-age']) { - return parseInt(this._rescc['max-age'], 10); - } - - const defaultMinTtl = this._rescc.immutable ? this._immutableMinTtl : 0; - - const dateValue = this.date(); - if (this._resHeaders.expires) { - const expires = Date.parse(this._resHeaders.expires); - // A cache recipient MUST interpret invalid date formats, especially the value "0", as representing a time in the past (i.e., "already expired"). - if (Number.isNaN(expires) || expires < dateValue) { - return 0; - } - return Math.max(defaultMinTtl, (expires - dateValue)/1000); - } - - if (this._resHeaders['last-modified']) { - const lastModified = Date.parse(this._resHeaders['last-modified']); - if (isFinite(lastModified) && dateValue > lastModified) { - return Math.max(defaultMinTtl, (dateValue - lastModified)/1000 * this._cacheHeuristic); - } - } - - return defaultMinTtl; - } - - timeToLive() { - return Math.max(0, this.maxAge() - this.age())*1000; - } - - stale() { - return this.maxAge() <= this.age(); - } - - static fromObject(obj) { - return new this(undefined, undefined, {_fromObject:obj}); - } - - _fromObject(obj) { - if (this._responseTime) throw Error("Reinitialized"); - if (!obj || obj.v !== 1) throw Error("Invalid serialization"); - - this._responseTime = obj.t; - this._isShared = obj.sh; - this._cacheHeuristic = obj.ch; - this._immutableMinTtl = obj.imm !== undefined ? obj.imm : 24*3600*1000; - this._status = obj.st; - this._resHeaders = obj.resh; - this._rescc = obj.rescc; - this._method = obj.m; - this._url = obj.u; - this._host = obj.h; - this._noAuthorization = obj.a; - this._reqHeaders = obj.reqh; - this._reqcc = obj.reqcc; - } - - toObject() { - return { - v:1, - t: this._responseTime, - sh: this._isShared, - ch: this._cacheHeuristic, - imm: this._immutableMinTtl, - st: this._status, - resh: this._resHeaders, - rescc: this._rescc, - m: this._method, - u: this._url, - h: this._host, - a: this._noAuthorization, - reqh: this._reqHeaders, - reqcc: this._reqcc, - }; - } - - /** - * Headers for sending to the origin server to revalidate stale response. - * Allows server to return 304 to allow reuse of the previous response. - * - * Hop by hop headers are always stripped. - * Revalidation headers may be added or removed, depending on request. - */ - revalidationHeaders(incomingReq) { - this._assertRequestHasHeaders(incomingReq); - const headers = this._copyWithoutHopByHopHeaders(incomingReq.headers); - - // This implementation does not understand range requests - delete headers['if-range']; - - if (!this._requestMatches(incomingReq, true) || !this.storable()) { // revalidation allowed via HEAD - // not for the same resource, or wasn't allowed to be cached anyway - delete headers['if-none-match']; - delete headers['if-modified-since']; - return headers; - } - - /* MUST send that entity-tag in any cache validation request (using If-Match or If-None-Match) if an entity-tag has been provided by the origin server. */ - if (this._resHeaders.etag) { - headers['if-none-match'] = headers['if-none-match'] ? `${headers['if-none-match']}, ${this._resHeaders.etag}` : this._resHeaders.etag; - } - - // Clients MAY issue simple (non-subrange) GET requests with either weak validators or strong validators. Clients MUST NOT use weak validators in other forms of request. - const forbidsWeakValidators = headers['accept-ranges'] || headers['if-match'] || headers['if-unmodified-since'] || (this._method && this._method != 'GET'); - - /* SHOULD send the Last-Modified value in non-subrange cache validation requests (using If-Modified-Since) if only a Last-Modified value has been provided by the origin server. - Note: This implementation does not understand partial responses (206) */ - if (forbidsWeakValidators) { - delete headers['if-modified-since']; - - if (headers['if-none-match']) { - const etags = headers['if-none-match'].split(/,/).filter(etag => { - return !/^\s*W\//.test(etag); - }); - if (!etags.length) { - delete headers['if-none-match']; - } else { - headers['if-none-match'] = etags.join(',').trim(); - } - } - } else if (this._resHeaders['last-modified'] && !headers['if-modified-since']) { - headers['if-modified-since'] = this._resHeaders['last-modified']; - } - - return headers; - } - - /** - * Creates new CachePolicy with information combined from the previews response, - * and the new revalidation response. - * - * Returns {policy, modified} where modified is a boolean indicating - * whether the response body has been modified, and old cached body can't be used. - * - * @return {Object} {policy: CachePolicy, modified: Boolean} - */ - revalidatedPolicy(request, response) { - this._assertRequestHasHeaders(request); - if (!response || !response.headers) { - throw Error("Response headers missing"); - } - - // These aren't going to be supported exactly, since one CachePolicy object - // doesn't know about all the other cached objects. - let matches = false; - if (response.status !== undefined && response.status != 304) { - matches = false; - } else if (response.headers.etag && !/^\s*W\//.test(response.headers.etag)) { - // "All of the stored responses with the same strong validator are selected. - // If none of the stored responses contain the same strong validator, - // then the cache MUST NOT use the new response to update any stored responses." - matches = this._resHeaders.etag && this._resHeaders.etag.replace(/^\s*W\//,'') === response.headers.etag; - } else if (this._resHeaders.etag && response.headers.etag) { - // "If the new response contains a weak validator and that validator corresponds - // to one of the cache's stored responses, - // then the most recent of those matching stored responses is selected for update." - matches = this._resHeaders.etag.replace(/^\s*W\//,'') === response.headers.etag.replace(/^\s*W\//,''); - } else if (this._resHeaders['last-modified']) { - matches = this._resHeaders['last-modified'] === response.headers['last-modified']; - } else { - // If the new response does not include any form of validator (such as in the case where - // a client generates an If-Modified-Since request from a source other than the Last-Modified - // response header field), and there is only one stored response, and that stored response also - // lacks a validator, then that stored response is selected for update. - if (!this._resHeaders.etag && !this._resHeaders['last-modified'] && - !response.headers.etag && !response.headers['last-modified']) { - matches = true; - } - } - - if (!matches) { - return { - policy: new this.constructor(request, response), - modified: true, - } - } - - // use other header fields provided in the 304 (Not Modified) response to replace all instances - // of the corresponding header fields in the stored response. - const headers = {}; - for(const k in this._resHeaders) { - headers[k] = k in response.headers && !excludedFromRevalidationUpdate[k] ? response.headers[k] : this._resHeaders[k]; - } - - const newResponse = Object.assign({}, response, { - status: this._status, - method: this._method, - headers, - }); - return { - policy: new this.constructor(request, newResponse), - modified: false, - }; - } -}; |