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Diffstat (limited to 'lib/fetch/util.js')
| -rw-r--r-- | lib/fetch/util.js | 1071 |
1 files changed, 1071 insertions, 0 deletions
diff --git a/lib/fetch/util.js b/lib/fetch/util.js new file mode 100644 index 0000000..b12142c --- /dev/null +++ b/lib/fetch/util.js @@ -0,0 +1,1071 @@ +'use strict' + +const { redirectStatusSet, referrerPolicySet: referrerPolicyTokens, badPortsSet } = require('./constants') +const { getGlobalOrigin } = require('./global') +const { performance } = require('perf_hooks') +const { isBlobLike, toUSVString, ReadableStreamFrom } = require('../core/util') +const assert = require('assert') +const { isUint8Array } = require('util/types') + +// https://nodejs.org/api/crypto.html#determining-if-crypto-support-is-unavailable +/** @type {import('crypto')|undefined} */ +let crypto + +try { + crypto = require('crypto') +} catch { + +} + +function responseURL (response) { + // https://fetch.spec.whatwg.org/#responses + // A response has an associated URL. It is a pointer to the last URL + // in response’s URL list and null if response’s URL list is empty. + const urlList = response.urlList + const length = urlList.length + return length === 0 ? null : urlList[length - 1].toString() +} + +// https://fetch.spec.whatwg.org/#concept-response-location-url +function responseLocationURL (response, requestFragment) { + // 1. If response’s status is not a redirect status, then return null. + if (!redirectStatusSet.has(response.status)) { + return null + } + + // 2. Let location be the result of extracting header list values given + // `Location` and response’s header list. + let location = response.headersList.get('location') + + // 3. If location is a header value, then set location to the result of + // parsing location with response’s URL. + if (location !== null && isValidHeaderValue(location)) { + location = new URL(location, responseURL(response)) + } + + // 4. If location is a URL whose fragment is null, then set location’s + // fragment to requestFragment. + if (location && !location.hash) { + location.hash = requestFragment + } + + // 5. Return location. + return location +} + +/** @returns {URL} */ +function requestCurrentURL (request) { + return request.urlList[request.urlList.length - 1] +} + +function requestBadPort (request) { + // 1. Let url be request’s current URL. + const url = requestCurrentURL(request) + + // 2. If url’s scheme is an HTTP(S) scheme and url’s port is a bad port, + // then return blocked. + if (urlIsHttpHttpsScheme(url) && badPortsSet.has(url.port)) { + return 'blocked' + } + + // 3. Return allowed. + return 'allowed' +} + +function isErrorLike (object) { + return object instanceof Error || ( + object?.constructor?.name === 'Error' || + object?.constructor?.name === 'DOMException' + ) +} + +// Check whether |statusText| is a ByteString and +// matches the Reason-Phrase token production. +// RFC 2616: https://tools.ietf.org/html/rfc2616 +// RFC 7230: https://tools.ietf.org/html/rfc7230 +// "reason-phrase = *( HTAB / SP / VCHAR / obs-text )" +// https://github.com/chromium/chromium/blob/94.0.4604.1/third_party/blink/renderer/core/fetch/response.cc#L116 +function isValidReasonPhrase (statusText) { + for (let i = 0; i < statusText.length; ++i) { + const c = statusText.charCodeAt(i) + if ( + !( + ( + c === 0x09 || // HTAB + (c >= 0x20 && c <= 0x7e) || // SP / VCHAR + (c >= 0x80 && c <= 0xff) + ) // obs-text + ) + ) { + return false + } + } + return true +} + +/** + * @see https://tools.ietf.org/html/rfc7230#section-3.2.6 + * @param {number} c + */ +function isTokenCharCode (c) { + switch (c) { + case 0x22: + case 0x28: + case 0x29: + case 0x2c: + case 0x2f: + case 0x3a: + case 0x3b: + case 0x3c: + case 0x3d: + case 0x3e: + case 0x3f: + case 0x40: + case 0x5b: + case 0x5c: + case 0x5d: + case 0x7b: + case 0x7d: + // DQUOTE and "(),/:;<=>?@[\]{}" + return false + default: + // VCHAR %x21-7E + return c >= 0x21 && c <= 0x7e + } +} + +/** + * @param {string} characters + */ +function isValidHTTPToken (characters) { + if (characters.length === 0) { + return false + } + for (let i = 0; i < characters.length; ++i) { + if (!isTokenCharCode(characters.charCodeAt(i))) { + return false + } + } + return true +} + +/** + * @see https://fetch.spec.whatwg.org/#header-name + * @param {string} potentialValue + */ +function isValidHeaderName (potentialValue) { + return isValidHTTPToken(potentialValue) +} + +/** + * @see https://fetch.spec.whatwg.org/#header-value + * @param {string} potentialValue + */ +function isValidHeaderValue (potentialValue) { + // - Has no leading or trailing HTTP tab or space bytes. + // - Contains no 0x00 (NUL) or HTTP newline bytes. + if ( + potentialValue.startsWith('\t') || + potentialValue.startsWith(' ') || + potentialValue.endsWith('\t') || + potentialValue.endsWith(' ') + ) { + return false + } + + if ( + potentialValue.includes('\0') || + potentialValue.includes('\r') || + potentialValue.includes('\n') + ) { + return false + } + + return true +} + +// https://w3c.github.io/webappsec-referrer-policy/#set-requests-referrer-policy-on-redirect +function setRequestReferrerPolicyOnRedirect (request, actualResponse) { + // Given a request request and a response actualResponse, this algorithm + // updates request’s referrer policy according to the Referrer-Policy + // header (if any) in actualResponse. + + // 1. Let policy be the result of executing § 8.1 Parse a referrer policy + // from a Referrer-Policy header on actualResponse. + + // 8.1 Parse a referrer policy from a Referrer-Policy header + // 1. Let policy-tokens be the result of extracting header list values given `Referrer-Policy` and response’s header list. + const { headersList } = actualResponse + // 2. Let policy be the empty string. + // 3. For each token in policy-tokens, if token is a referrer policy and token is not the empty string, then set policy to token. + // 4. Return policy. + const policyHeader = (headersList.get('referrer-policy') ?? '').split(',') + + // Note: As the referrer-policy can contain multiple policies + // separated by comma, we need to loop through all of them + // and pick the first valid one. + // Ref: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referrer-Policy#specify_a_fallback_policy + let policy = '' + if (policyHeader.length > 0) { + // The right-most policy takes precedence. + // The left-most policy is the fallback. + for (let i = policyHeader.length; i !== 0; i--) { + const token = policyHeader[i - 1].trim() + if (referrerPolicyTokens.has(token)) { + policy = token + break + } + } + } + + // 2. If policy is not the empty string, then set request’s referrer policy to policy. + if (policy !== '') { + request.referrerPolicy = policy + } +} + +// https://fetch.spec.whatwg.org/#cross-origin-resource-policy-check +function crossOriginResourcePolicyCheck () { + // TODO + return 'allowed' +} + +// https://fetch.spec.whatwg.org/#concept-cors-check +function corsCheck () { + // TODO + return 'success' +} + +// https://fetch.spec.whatwg.org/#concept-tao-check +function TAOCheck () { + // TODO + return 'success' +} + +function appendFetchMetadata (httpRequest) { + // https://w3c.github.io/webappsec-fetch-metadata/#sec-fetch-dest-header + // TODO + + // https://w3c.github.io/webappsec-fetch-metadata/#sec-fetch-mode-header + + // 1. Assert: r’s url is a potentially trustworthy URL. + // TODO + + // 2. Let header be a Structured Header whose value is a token. + let header = null + + // 3. Set header’s value to r’s mode. + header = httpRequest.mode + + // 4. Set a structured field value `Sec-Fetch-Mode`/header in r’s header list. + httpRequest.headersList.set('sec-fetch-mode', header) + + // https://w3c.github.io/webappsec-fetch-metadata/#sec-fetch-site-header + // TODO + + // https://w3c.github.io/webappsec-fetch-metadata/#sec-fetch-user-header + // TODO +} + +// https://fetch.spec.whatwg.org/#append-a-request-origin-header +function appendRequestOriginHeader (request) { + // 1. Let serializedOrigin be the result of byte-serializing a request origin with request. + let serializedOrigin = request.origin + + // 2. If request’s response tainting is "cors" or request’s mode is "websocket", then append (`Origin`, serializedOrigin) to request’s header list. + if (request.responseTainting === 'cors' || request.mode === 'websocket') { + if (serializedOrigin) { + request.headersList.append('origin', serializedOrigin) + } + + // 3. Otherwise, if request’s method is neither `GET` nor `HEAD`, then: + } else if (request.method !== 'GET' && request.method !== 'HEAD') { + // 1. Switch on request’s referrer policy: + switch (request.referrerPolicy) { + case 'no-referrer': + // Set serializedOrigin to `null`. + serializedOrigin = null + break + case 'no-referrer-when-downgrade': + case 'strict-origin': + case 'strict-origin-when-cross-origin': + // If request’s origin is a tuple origin, its scheme is "https", and request’s current URL’s scheme is not "https", then set serializedOrigin to `null`. + if (request.origin && urlHasHttpsScheme(request.origin) && !urlHasHttpsScheme(requestCurrentURL(request))) { + serializedOrigin = null + } + break + case 'same-origin': + // If request’s origin is not same origin with request’s current URL’s origin, then set serializedOrigin to `null`. + if (!sameOrigin(request, requestCurrentURL(request))) { + serializedOrigin = null + } + break + default: + // Do nothing. + } + + if (serializedOrigin) { + // 2. Append (`Origin`, serializedOrigin) to request’s header list. + request.headersList.append('origin', serializedOrigin) + } + } +} + +function coarsenedSharedCurrentTime (crossOriginIsolatedCapability) { + // TODO + return performance.now() +} + +// https://fetch.spec.whatwg.org/#create-an-opaque-timing-info +function createOpaqueTimingInfo (timingInfo) { + return { + startTime: timingInfo.startTime ?? 0, + redirectStartTime: 0, + redirectEndTime: 0, + postRedirectStartTime: timingInfo.startTime ?? 0, + finalServiceWorkerStartTime: 0, + finalNetworkResponseStartTime: 0, + finalNetworkRequestStartTime: 0, + endTime: 0, + encodedBodySize: 0, + decodedBodySize: 0, + finalConnectionTimingInfo: null + } +} + +// https://html.spec.whatwg.org/multipage/origin.html#policy-container +function makePolicyContainer () { + // Note: the fetch spec doesn't make use of embedder policy or CSP list + return { + referrerPolicy: 'strict-origin-when-cross-origin' + } +} + +// https://html.spec.whatwg.org/multipage/origin.html#clone-a-policy-container +function clonePolicyContainer (policyContainer) { + return { + referrerPolicy: policyContainer.referrerPolicy + } +} + +// https://w3c.github.io/webappsec-referrer-policy/#determine-requests-referrer +function determineRequestsReferrer (request) { + // 1. Let policy be request's referrer policy. + const policy = request.referrerPolicy + + // Note: policy cannot (shouldn't) be null or an empty string. + assert(policy) + + // 2. Let environment be request’s client. + + let referrerSource = null + + // 3. Switch on request’s referrer: + if (request.referrer === 'client') { + // Note: node isn't a browser and doesn't implement document/iframes, + // so we bypass this step and replace it with our own. + + const globalOrigin = getGlobalOrigin() + + if (!globalOrigin || globalOrigin.origin === 'null') { + return 'no-referrer' + } + + // note: we need to clone it as it's mutated + referrerSource = new URL(globalOrigin) + } else if (request.referrer instanceof URL) { + // Let referrerSource be request’s referrer. + referrerSource = request.referrer + } + + // 4. Let request’s referrerURL be the result of stripping referrerSource for + // use as a referrer. + let referrerURL = stripURLForReferrer(referrerSource) + + // 5. Let referrerOrigin be the result of stripping referrerSource for use as + // a referrer, with the origin-only flag set to true. + const referrerOrigin = stripURLForReferrer(referrerSource, true) + + // 6. If the result of serializing referrerURL is a string whose length is + // greater than 4096, set referrerURL to referrerOrigin. + if (referrerURL.toString().length > 4096) { + referrerURL = referrerOrigin + } + + const areSameOrigin = sameOrigin(request, referrerURL) + const isNonPotentiallyTrustWorthy = isURLPotentiallyTrustworthy(referrerURL) && + !isURLPotentiallyTrustworthy(request.url) + + // 8. Execute the switch statements corresponding to the value of policy: + switch (policy) { + case 'origin': return referrerOrigin != null ? referrerOrigin : stripURLForReferrer(referrerSource, true) + case 'unsafe-url': return referrerURL + case 'same-origin': + return areSameOrigin ? referrerOrigin : 'no-referrer' + case 'origin-when-cross-origin': + return areSameOrigin ? referrerURL : referrerOrigin + case 'strict-origin-when-cross-origin': { + const currentURL = requestCurrentURL(request) + + // 1. If the origin of referrerURL and the origin of request’s current + // URL are the same, then return referrerURL. + if (sameOrigin(referrerURL, currentURL)) { + return referrerURL + } + + // 2. If referrerURL is a potentially trustworthy URL and request’s + // current URL is not a potentially trustworthy URL, then return no + // referrer. + if (isURLPotentiallyTrustworthy(referrerURL) && !isURLPotentiallyTrustworthy(currentURL)) { + return 'no-referrer' + } + + // 3. Return referrerOrigin. + return referrerOrigin + } + case 'strict-origin': // eslint-disable-line + /** + * 1. If referrerURL is a potentially trustworthy URL and + * request’s current URL is not a potentially trustworthy URL, + * then return no referrer. + * 2. Return referrerOrigin + */ + case 'no-referrer-when-downgrade': // eslint-disable-line + /** + * 1. If referrerURL is a potentially trustworthy URL and + * request’s current URL is not a potentially trustworthy URL, + * then return no referrer. + * 2. Return referrerOrigin + */ + + default: // eslint-disable-line + return isNonPotentiallyTrustWorthy ? 'no-referrer' : referrerOrigin + } +} + +/** + * @see https://w3c.github.io/webappsec-referrer-policy/#strip-url + * @param {URL} url + * @param {boolean|undefined} originOnly + */ +function stripURLForReferrer (url, originOnly) { + // 1. Assert: url is a URL. + assert(url instanceof URL) + + // 2. If url’s scheme is a local scheme, then return no referrer. + if (url.protocol === 'file:' || url.protocol === 'about:' || url.protocol === 'blank:') { + return 'no-referrer' + } + + // 3. Set url’s username to the empty string. + url.username = '' + + // 4. Set url’s password to the empty string. + url.password = '' + + // 5. Set url’s fragment to null. + url.hash = '' + + // 6. If the origin-only flag is true, then: + if (originOnly) { + // 1. Set url’s path to « the empty string ». + url.pathname = '' + + // 2. Set url’s query to null. + url.search = '' + } + + // 7. Return url. + return url +} + +function isURLPotentiallyTrustworthy (url) { + if (!(url instanceof URL)) { + return false + } + + // If child of about, return true + if (url.href === 'about:blank' || url.href === 'about:srcdoc') { + return true + } + + // If scheme is data, return true + if (url.protocol === 'data:') return true + + // If file, return true + if (url.protocol === 'file:') return true + + return isOriginPotentiallyTrustworthy(url.origin) + + function isOriginPotentiallyTrustworthy (origin) { + // If origin is explicitly null, return false + if (origin == null || origin === 'null') return false + + const originAsURL = new URL(origin) + + // If secure, return true + if (originAsURL.protocol === 'https:' || originAsURL.protocol === 'wss:') { + return true + } + + // If localhost or variants, return true + if (/^127(?:\.[0-9]+){0,2}\.[0-9]+$|^\[(?:0*:)*?:?0*1\]$/.test(originAsURL.hostname) || + (originAsURL.hostname === 'localhost' || originAsURL.hostname.includes('localhost.')) || + (originAsURL.hostname.endsWith('.localhost'))) { + return true + } + + // If any other, return false + return false + } +} + +/** + * @see https://w3c.github.io/webappsec-subresource-integrity/#does-response-match-metadatalist + * @param {Uint8Array} bytes + * @param {string} metadataList + */ +function bytesMatch (bytes, metadataList) { + // If node is not built with OpenSSL support, we cannot check + // a request's integrity, so allow it by default (the spec will + // allow requests if an invalid hash is given, as precedence). + /* istanbul ignore if: only if node is built with --without-ssl */ + if (crypto === undefined) { + return true + } + + // 1. Let parsedMetadata be the result of parsing metadataList. + const parsedMetadata = parseMetadata(metadataList) + + // 2. If parsedMetadata is no metadata, return true. + if (parsedMetadata === 'no metadata') { + return true + } + + // 3. If parsedMetadata is the empty set, return true. + if (parsedMetadata.length === 0) { + return true + } + + // 4. Let metadata be the result of getting the strongest + // metadata from parsedMetadata. + const list = parsedMetadata.sort((c, d) => d.algo.localeCompare(c.algo)) + // get the strongest algorithm + const strongest = list[0].algo + // get all entries that use the strongest algorithm; ignore weaker + const metadata = list.filter((item) => item.algo === strongest) + + // 5. For each item in metadata: + for (const item of metadata) { + // 1. Let algorithm be the alg component of item. + const algorithm = item.algo + + // 2. Let expectedValue be the val component of item. + let expectedValue = item.hash + + // See https://github.com/web-platform-tests/wpt/commit/e4c5cc7a5e48093220528dfdd1c4012dc3837a0e + // "be liberal with padding". This is annoying, and it's not even in the spec. + + if (expectedValue.endsWith('==')) { + expectedValue = expectedValue.slice(0, -2) + } + + // 3. Let actualValue be the result of applying algorithm to bytes. + let actualValue = crypto.createHash(algorithm).update(bytes).digest('base64') + + if (actualValue.endsWith('==')) { + actualValue = actualValue.slice(0, -2) + } + + // 4. If actualValue is a case-sensitive match for expectedValue, + // return true. + if (actualValue === expectedValue) { + return true + } + + let actualBase64URL = crypto.createHash(algorithm).update(bytes).digest('base64url') + + if (actualBase64URL.endsWith('==')) { + actualBase64URL = actualBase64URL.slice(0, -2) + } + + if (actualBase64URL === expectedValue) { + return true + } + } + + // 6. Return false. + return false +} + +// https://w3c.github.io/webappsec-subresource-integrity/#grammardef-hash-with-options +// https://www.w3.org/TR/CSP2/#source-list-syntax +// https://www.rfc-editor.org/rfc/rfc5234#appendix-B.1 +const parseHashWithOptions = /((?<algo>sha256|sha384|sha512)-(?<hash>[A-z0-9+/]{1}.*={0,2}))( +[\x21-\x7e]?)?/i + +/** + * @see https://w3c.github.io/webappsec-subresource-integrity/#parse-metadata + * @param {string} metadata + */ +function parseMetadata (metadata) { + // 1. Let result be the empty set. + /** @type {{ algo: string, hash: string }[]} */ + const result = [] + + // 2. Let empty be equal to true. + let empty = true + + const supportedHashes = crypto.getHashes() + + // 3. For each token returned by splitting metadata on spaces: + for (const token of metadata.split(' ')) { + // 1. Set empty to false. + empty = false + + // 2. Parse token as a hash-with-options. + const parsedToken = parseHashWithOptions.exec(token) + + // 3. If token does not parse, continue to the next token. + if (parsedToken === null || parsedToken.groups === undefined) { + // Note: Chromium blocks the request at this point, but Firefox + // gives a warning that an invalid integrity was given. The + // correct behavior is to ignore these, and subsequently not + // check the integrity of the resource. + continue + } + + // 4. Let algorithm be the hash-algo component of token. + const algorithm = parsedToken.groups.algo + + // 5. If algorithm is a hash function recognized by the user + // agent, add the parsed token to result. + if (supportedHashes.includes(algorithm.toLowerCase())) { + result.push(parsedToken.groups) + } + } + + // 4. Return no metadata if empty is true, otherwise return result. + if (empty === true) { + return 'no metadata' + } + + return result +} + +// https://w3c.github.io/webappsec-upgrade-insecure-requests/#upgrade-request +function tryUpgradeRequestToAPotentiallyTrustworthyURL (request) { + // TODO +} + +/** + * @link {https://html.spec.whatwg.org/multipage/origin.html#same-origin} + * @param {URL} A + * @param {URL} B + */ +function sameOrigin (A, B) { + // 1. If A and B are the same opaque origin, then return true. + if (A.origin === B.origin && A.origin === 'null') { + return true + } + + // 2. If A and B are both tuple origins and their schemes, + // hosts, and port are identical, then return true. + if (A.protocol === B.protocol && A.hostname === B.hostname && A.port === B.port) { + return true + } + + // 3. Return false. + return false +} + +function createDeferredPromise () { + let res + let rej + const promise = new Promise((resolve, reject) => { + res = resolve + rej = reject + }) + + return { promise, resolve: res, reject: rej } +} + +function isAborted (fetchParams) { + return fetchParams.controller.state === 'aborted' +} + +function isCancelled (fetchParams) { + return fetchParams.controller.state === 'aborted' || + fetchParams.controller.state === 'terminated' +} + +const normalizeMethodRecord = { + delete: 'DELETE', + DELETE: 'DELETE', + get: 'GET', + GET: 'GET', + head: 'HEAD', + HEAD: 'HEAD', + options: 'OPTIONS', + OPTIONS: 'OPTIONS', + post: 'POST', + POST: 'POST', + put: 'PUT', + PUT: 'PUT' +} + +// Note: object prototypes should not be able to be referenced. e.g. `Object#hasOwnProperty`. +Object.setPrototypeOf(normalizeMethodRecord, null) + +/** + * @see https://fetch.spec.whatwg.org/#concept-method-normalize + * @param {string} method + */ +function normalizeMethod (method) { + return normalizeMethodRecord[method.toLowerCase()] ?? method +} + +// https://infra.spec.whatwg.org/#serialize-a-javascript-value-to-a-json-string +function serializeJavascriptValueToJSONString (value) { + // 1. Let result be ? Call(%JSON.stringify%, undefined, « value »). + const result = JSON.stringify(value) + + // 2. If result is undefined, then throw a TypeError. + if (result === undefined) { + throw new TypeError('Value is not JSON serializable') + } + + // 3. Assert: result is a string. + assert(typeof result === 'string') + + // 4. Return result. + return result +} + +// https://tc39.es/ecma262/#sec-%25iteratorprototype%25-object +const esIteratorPrototype = Object.getPrototypeOf(Object.getPrototypeOf([][Symbol.iterator]())) + +/** + * @see https://webidl.spec.whatwg.org/#dfn-iterator-prototype-object + * @param {() => unknown[]} iterator + * @param {string} name name of the instance + * @param {'key'|'value'|'key+value'} kind + */ +function makeIterator (iterator, name, kind) { + const object = { + index: 0, + kind, + target: iterator + } + + const i = { + next () { + // 1. Let interface be the interface for which the iterator prototype object exists. + + // 2. Let thisValue be the this value. + + // 3. Let object be ? ToObject(thisValue). + + // 4. If object is a platform object, then perform a security + // check, passing: + + // 5. If object is not a default iterator object for interface, + // then throw a TypeError. + if (Object.getPrototypeOf(this) !== i) { + throw new TypeError( + `'next' called on an object that does not implement interface ${name} Iterator.` + ) + } + + // 6. Let index be object’s index. + // 7. Let kind be object’s kind. + // 8. Let values be object’s target's value pairs to iterate over. + const { index, kind, target } = object + const values = target() + + // 9. Let len be the length of values. + const len = values.length + + // 10. If index is greater than or equal to len, then return + // CreateIterResultObject(undefined, true). + if (index >= len) { + return { value: undefined, done: true } + } + + // 11. Let pair be the entry in values at index index. + const pair = values[index] + + // 12. Set object’s index to index + 1. + object.index = index + 1 + + // 13. Return the iterator result for pair and kind. + return iteratorResult(pair, kind) + }, + // The class string of an iterator prototype object for a given interface is the + // result of concatenating the identifier of the interface and the string " Iterator". + [Symbol.toStringTag]: `${name} Iterator` + } + + // The [[Prototype]] internal slot of an iterator prototype object must be %IteratorPrototype%. + Object.setPrototypeOf(i, esIteratorPrototype) + // esIteratorPrototype needs to be the prototype of i + // which is the prototype of an empty object. Yes, it's confusing. + return Object.setPrototypeOf({}, i) +} + +// https://webidl.spec.whatwg.org/#iterator-result +function iteratorResult (pair, kind) { + let result + + // 1. Let result be a value determined by the value of kind: + switch (kind) { + case 'key': { + // 1. Let idlKey be pair’s key. + // 2. Let key be the result of converting idlKey to an + // ECMAScript value. + // 3. result is key. + result = pair[0] + break + } + case 'value': { + // 1. Let idlValue be pair’s value. + // 2. Let value be the result of converting idlValue to + // an ECMAScript value. + // 3. result is value. + result = pair[1] + break + } + case 'key+value': { + // 1. Let idlKey be pair’s key. + // 2. Let idlValue be pair’s value. + // 3. Let key be the result of converting idlKey to an + // ECMAScript value. + // 4. Let value be the result of converting idlValue to + // an ECMAScript value. + // 5. Let array be ! ArrayCreate(2). + // 6. Call ! CreateDataProperty(array, "0", key). + // 7. Call ! CreateDataProperty(array, "1", value). + // 8. result is array. + result = pair + break + } + } + + // 2. Return CreateIterResultObject(result, false). + return { value: result, done: false } +} + +/** + * @see https://fetch.spec.whatwg.org/#body-fully-read + */ +async function fullyReadBody (body, processBody, processBodyError) { + // 1. If taskDestination is null, then set taskDestination to + // the result of starting a new parallel queue. + + // 2. Let successSteps given a byte sequence bytes be to queue a + // fetch task to run processBody given bytes, with taskDestination. + const successSteps = processBody + + // 3. Let errorSteps be to queue a fetch task to run processBodyError, + // with taskDestination. + const errorSteps = processBodyError + + // 4. Let reader be the result of getting a reader for body’s stream. + // If that threw an exception, then run errorSteps with that + // exception and return. + let reader + + try { + reader = body.stream.getReader() + } catch (e) { + errorSteps(e) + return + } + + // 5. Read all bytes from reader, given successSteps and errorSteps. + try { + const result = await readAllBytes(reader) + successSteps(result) + } catch (e) { + errorSteps(e) + } +} + +/** @type {ReadableStream} */ +let ReadableStream = globalThis.ReadableStream + +function isReadableStreamLike (stream) { + if (!ReadableStream) { + ReadableStream = require('stream/web').ReadableStream + } + + return stream instanceof ReadableStream || ( + stream[Symbol.toStringTag] === 'ReadableStream' && + typeof stream.tee === 'function' + ) +} + +const MAXIMUM_ARGUMENT_LENGTH = 65535 + +/** + * @see https://infra.spec.whatwg.org/#isomorphic-decode + * @param {number[]|Uint8Array} input + */ +function isomorphicDecode (input) { + // 1. To isomorphic decode a byte sequence input, return a string whose code point + // length is equal to input’s length and whose code points have the same values + // as the values of input’s bytes, in the same order. + + if (input.length < MAXIMUM_ARGUMENT_LENGTH) { + return String.fromCharCode(...input) + } + + return input.reduce((previous, current) => previous + String.fromCharCode(current), '') +} + +/** + * @param {ReadableStreamController<Uint8Array>} controller + */ +function readableStreamClose (controller) { + try { + controller.close() + } catch (err) { + // TODO: add comment explaining why this error occurs. + if (!err.message.includes('Controller is already closed')) { + throw err + } + } +} + +/** + * @see https://infra.spec.whatwg.org/#isomorphic-encode + * @param {string} input + */ +function isomorphicEncode (input) { + // 1. Assert: input contains no code points greater than U+00FF. + for (let i = 0; i < input.length; i++) { + assert(input.charCodeAt(i) <= 0xFF) + } + + // 2. Return a byte sequence whose length is equal to input’s code + // point length and whose bytes have the same values as the + // values of input’s code points, in the same order + return input +} + +/** + * @see https://streams.spec.whatwg.org/#readablestreamdefaultreader-read-all-bytes + * @see https://streams.spec.whatwg.org/#read-loop + * @param {ReadableStreamDefaultReader} reader + */ +async function readAllBytes (reader) { + const bytes = [] + let byteLength = 0 + + while (true) { + const { done, value: chunk } = await reader.read() + + if (done) { + // 1. Call successSteps with bytes. + return Buffer.concat(bytes, byteLength) + } + + // 1. If chunk is not a Uint8Array object, call failureSteps + // with a TypeError and abort these steps. + if (!isUint8Array(chunk)) { + throw new TypeError('Received non-Uint8Array chunk') + } + + // 2. Append the bytes represented by chunk to bytes. + bytes.push(chunk) + byteLength += chunk.length + + // 3. Read-loop given reader, bytes, successSteps, and failureSteps. + } +} + +/** + * @see https://fetch.spec.whatwg.org/#is-local + * @param {URL} url + */ +function urlIsLocal (url) { + assert('protocol' in url) // ensure it's a url object + + const protocol = url.protocol + + return protocol === 'about:' || protocol === 'blob:' || protocol === 'data:' +} + +/** + * @param {string|URL} url + */ +function urlHasHttpsScheme (url) { + if (typeof url === 'string') { + return url.startsWith('https:') + } + + return url.protocol === 'https:' +} + +/** + * @see https://fetch.spec.whatwg.org/#http-scheme + * @param {URL} url + */ +function urlIsHttpHttpsScheme (url) { + assert('protocol' in url) // ensure it's a url object + + const protocol = url.protocol + + return protocol === 'http:' || protocol === 'https:' +} + +/** + * Fetch supports node >= 16.8.0, but Object.hasOwn was added in v16.9.0. + */ +const hasOwn = Object.hasOwn || ((dict, key) => Object.prototype.hasOwnProperty.call(dict, key)) + +module.exports = { + isAborted, + isCancelled, + createDeferredPromise, + ReadableStreamFrom, + toUSVString, + tryUpgradeRequestToAPotentiallyTrustworthyURL, + coarsenedSharedCurrentTime, + determineRequestsReferrer, + makePolicyContainer, + clonePolicyContainer, + appendFetchMetadata, + appendRequestOriginHeader, + TAOCheck, + corsCheck, + crossOriginResourcePolicyCheck, + createOpaqueTimingInfo, + setRequestReferrerPolicyOnRedirect, + isValidHTTPToken, + requestBadPort, + requestCurrentURL, + responseURL, + responseLocationURL, + isBlobLike, + isURLPotentiallyTrustworthy, + isValidReasonPhrase, + sameOrigin, + normalizeMethod, + serializeJavascriptValueToJSONString, + makeIterator, + isValidHeaderName, + isValidHeaderValue, + hasOwn, + isErrorLike, + fullyReadBody, + bytesMatch, + isReadableStreamLike, + readableStreamClose, + isomorphicEncode, + isomorphicDecode, + urlIsLocal, + urlHasHttpsScheme, + urlIsHttpHttpsScheme, + readAllBytes, + normalizeMethodRecord +} |