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Diffstat (limited to 'node_modules/undici/lib/fetch/dataURL.js')
| -rw-r--r-- | node_modules/undici/lib/fetch/dataURL.js | 627 |
1 files changed, 627 insertions, 0 deletions
diff --git a/node_modules/undici/lib/fetch/dataURL.js b/node_modules/undici/lib/fetch/dataURL.js new file mode 100644 index 0000000..7b6a606 --- /dev/null +++ b/node_modules/undici/lib/fetch/dataURL.js @@ -0,0 +1,627 @@ +const assert = require('assert') +const { atob } = require('buffer') +const { isomorphicDecode } = require('./util') + +const encoder = new TextEncoder() + +/** + * @see https://mimesniff.spec.whatwg.org/#http-token-code-point + */ +const HTTP_TOKEN_CODEPOINTS = /^[!#$%&'*+-.^_|~A-Za-z0-9]+$/ +const HTTP_WHITESPACE_REGEX = /(\u000A|\u000D|\u0009|\u0020)/ // eslint-disable-line +/** + * @see https://mimesniff.spec.whatwg.org/#http-quoted-string-token-code-point + */ +const HTTP_QUOTED_STRING_TOKENS = /[\u0009|\u0020-\u007E|\u0080-\u00FF]/ // eslint-disable-line + +// https://fetch.spec.whatwg.org/#data-url-processor +/** @param {URL} dataURL */ +function dataURLProcessor (dataURL) { + // 1. Assert: dataURL’s scheme is "data". + assert(dataURL.protocol === 'data:') + + // 2. Let input be the result of running the URL + // serializer on dataURL with exclude fragment + // set to true. + let input = URLSerializer(dataURL, true) + + // 3. Remove the leading "data:" string from input. + input = input.slice(5) + + // 4. Let position point at the start of input. + const position = { position: 0 } + + // 5. Let mimeType be the result of collecting a + // sequence of code points that are not equal + // to U+002C (,), given position. + let mimeType = collectASequenceOfCodePointsFast( + ',', + input, + position + ) + + // 6. Strip leading and trailing ASCII whitespace + // from mimeType. + // Undici implementation note: we need to store the + // length because if the mimetype has spaces removed, + // the wrong amount will be sliced from the input in + // step #9 + const mimeTypeLength = mimeType.length + mimeType = removeASCIIWhitespace(mimeType, true, true) + + // 7. If position is past the end of input, then + // return failure + if (position.position >= input.length) { + return 'failure' + } + + // 8. Advance position by 1. + position.position++ + + // 9. Let encodedBody be the remainder of input. + const encodedBody = input.slice(mimeTypeLength + 1) + + // 10. Let body be the percent-decoding of encodedBody. + let body = stringPercentDecode(encodedBody) + + // 11. If mimeType ends with U+003B (;), followed by + // zero or more U+0020 SPACE, followed by an ASCII + // case-insensitive match for "base64", then: + if (/;(\u0020){0,}base64$/i.test(mimeType)) { + // 1. Let stringBody be the isomorphic decode of body. + const stringBody = isomorphicDecode(body) + + // 2. Set body to the forgiving-base64 decode of + // stringBody. + body = forgivingBase64(stringBody) + + // 3. If body is failure, then return failure. + if (body === 'failure') { + return 'failure' + } + + // 4. Remove the last 6 code points from mimeType. + mimeType = mimeType.slice(0, -6) + + // 5. Remove trailing U+0020 SPACE code points from mimeType, + // if any. + mimeType = mimeType.replace(/(\u0020)+$/, '') + + // 6. Remove the last U+003B (;) code point from mimeType. + mimeType = mimeType.slice(0, -1) + } + + // 12. If mimeType starts with U+003B (;), then prepend + // "text/plain" to mimeType. + if (mimeType.startsWith(';')) { + mimeType = 'text/plain' + mimeType + } + + // 13. Let mimeTypeRecord be the result of parsing + // mimeType. + let mimeTypeRecord = parseMIMEType(mimeType) + + // 14. If mimeTypeRecord is failure, then set + // mimeTypeRecord to text/plain;charset=US-ASCII. + if (mimeTypeRecord === 'failure') { + mimeTypeRecord = parseMIMEType('text/plain;charset=US-ASCII') + } + + // 15. Return a new data: URL struct whose MIME + // type is mimeTypeRecord and body is body. + // https://fetch.spec.whatwg.org/#data-url-struct + return { mimeType: mimeTypeRecord, body } +} + +// https://url.spec.whatwg.org/#concept-url-serializer +/** + * @param {URL} url + * @param {boolean} excludeFragment + */ +function URLSerializer (url, excludeFragment = false) { + if (!excludeFragment) { + return url.href + } + + const href = url.href + const hashLength = url.hash.length + + return hashLength === 0 ? href : href.substring(0, href.length - hashLength) +} + +// https://infra.spec.whatwg.org/#collect-a-sequence-of-code-points +/** + * @param {(char: string) => boolean} condition + * @param {string} input + * @param {{ position: number }} position + */ +function collectASequenceOfCodePoints (condition, input, position) { + // 1. Let result be the empty string. + let result = '' + + // 2. While position doesn’t point past the end of input and the + // code point at position within input meets the condition condition: + while (position.position < input.length && condition(input[position.position])) { + // 1. Append that code point to the end of result. + result += input[position.position] + + // 2. Advance position by 1. + position.position++ + } + + // 3. Return result. + return result +} + +/** + * A faster collectASequenceOfCodePoints that only works when comparing a single character. + * @param {string} char + * @param {string} input + * @param {{ position: number }} position + */ +function collectASequenceOfCodePointsFast (char, input, position) { + const idx = input.indexOf(char, position.position) + const start = position.position + + if (idx === -1) { + position.position = input.length + return input.slice(start) + } + + position.position = idx + return input.slice(start, position.position) +} + +// https://url.spec.whatwg.org/#string-percent-decode +/** @param {string} input */ +function stringPercentDecode (input) { + // 1. Let bytes be the UTF-8 encoding of input. + const bytes = encoder.encode(input) + + // 2. Return the percent-decoding of bytes. + return percentDecode(bytes) +} + +// https://url.spec.whatwg.org/#percent-decode +/** @param {Uint8Array} input */ +function percentDecode (input) { + // 1. Let output be an empty byte sequence. + /** @type {number[]} */ + const output = [] + + // 2. For each byte byte in input: + for (let i = 0; i < input.length; i++) { + const byte = input[i] + + // 1. If byte is not 0x25 (%), then append byte to output. + if (byte !== 0x25) { + output.push(byte) + + // 2. Otherwise, if byte is 0x25 (%) and the next two bytes + // after byte in input are not in the ranges + // 0x30 (0) to 0x39 (9), 0x41 (A) to 0x46 (F), + // and 0x61 (a) to 0x66 (f), all inclusive, append byte + // to output. + } else if ( + byte === 0x25 && + !/^[0-9A-Fa-f]{2}$/i.test(String.fromCharCode(input[i + 1], input[i + 2])) + ) { + output.push(0x25) + + // 3. Otherwise: + } else { + // 1. Let bytePoint be the two bytes after byte in input, + // decoded, and then interpreted as hexadecimal number. + const nextTwoBytes = String.fromCharCode(input[i + 1], input[i + 2]) + const bytePoint = Number.parseInt(nextTwoBytes, 16) + + // 2. Append a byte whose value is bytePoint to output. + output.push(bytePoint) + + // 3. Skip the next two bytes in input. + i += 2 + } + } + + // 3. Return output. + return Uint8Array.from(output) +} + +// https://mimesniff.spec.whatwg.org/#parse-a-mime-type +/** @param {string} input */ +function parseMIMEType (input) { + // 1. Remove any leading and trailing HTTP whitespace + // from input. + input = removeHTTPWhitespace(input, true, true) + + // 2. Let position be a position variable for input, + // initially pointing at the start of input. + const position = { position: 0 } + + // 3. Let type be the result of collecting a sequence + // of code points that are not U+002F (/) from + // input, given position. + const type = collectASequenceOfCodePointsFast( + '/', + input, + position + ) + + // 4. If type is the empty string or does not solely + // contain HTTP token code points, then return failure. + // https://mimesniff.spec.whatwg.org/#http-token-code-point + if (type.length === 0 || !HTTP_TOKEN_CODEPOINTS.test(type)) { + return 'failure' + } + + // 5. If position is past the end of input, then return + // failure + if (position.position > input.length) { + return 'failure' + } + + // 6. Advance position by 1. (This skips past U+002F (/).) + position.position++ + + // 7. Let subtype be the result of collecting a sequence of + // code points that are not U+003B (;) from input, given + // position. + let subtype = collectASequenceOfCodePointsFast( + ';', + input, + position + ) + + // 8. Remove any trailing HTTP whitespace from subtype. + subtype = removeHTTPWhitespace(subtype, false, true) + + // 9. If subtype is the empty string or does not solely + // contain HTTP token code points, then return failure. + if (subtype.length === 0 || !HTTP_TOKEN_CODEPOINTS.test(subtype)) { + return 'failure' + } + + const typeLowercase = type.toLowerCase() + const subtypeLowercase = subtype.toLowerCase() + + // 10. Let mimeType be a new MIME type record whose type + // is type, in ASCII lowercase, and subtype is subtype, + // in ASCII lowercase. + // https://mimesniff.spec.whatwg.org/#mime-type + const mimeType = { + type: typeLowercase, + subtype: subtypeLowercase, + /** @type {Map<string, string>} */ + parameters: new Map(), + // https://mimesniff.spec.whatwg.org/#mime-type-essence + essence: `${typeLowercase}/${subtypeLowercase}` + } + + // 11. While position is not past the end of input: + while (position.position < input.length) { + // 1. Advance position by 1. (This skips past U+003B (;).) + position.position++ + + // 2. Collect a sequence of code points that are HTTP + // whitespace from input given position. + collectASequenceOfCodePoints( + // https://fetch.spec.whatwg.org/#http-whitespace + char => HTTP_WHITESPACE_REGEX.test(char), + input, + position + ) + + // 3. Let parameterName be the result of collecting a + // sequence of code points that are not U+003B (;) + // or U+003D (=) from input, given position. + let parameterName = collectASequenceOfCodePoints( + (char) => char !== ';' && char !== '=', + input, + position + ) + + // 4. Set parameterName to parameterName, in ASCII + // lowercase. + parameterName = parameterName.toLowerCase() + + // 5. If position is not past the end of input, then: + if (position.position < input.length) { + // 1. If the code point at position within input is + // U+003B (;), then continue. + if (input[position.position] === ';') { + continue + } + + // 2. Advance position by 1. (This skips past U+003D (=).) + position.position++ + } + + // 6. If position is past the end of input, then break. + if (position.position > input.length) { + break + } + + // 7. Let parameterValue be null. + let parameterValue = null + + // 8. If the code point at position within input is + // U+0022 ("), then: + if (input[position.position] === '"') { + // 1. Set parameterValue to the result of collecting + // an HTTP quoted string from input, given position + // and the extract-value flag. + parameterValue = collectAnHTTPQuotedString(input, position, true) + + // 2. Collect a sequence of code points that are not + // U+003B (;) from input, given position. + collectASequenceOfCodePointsFast( + ';', + input, + position + ) + + // 9. Otherwise: + } else { + // 1. Set parameterValue to the result of collecting + // a sequence of code points that are not U+003B (;) + // from input, given position. + parameterValue = collectASequenceOfCodePointsFast( + ';', + input, + position + ) + + // 2. Remove any trailing HTTP whitespace from parameterValue. + parameterValue = removeHTTPWhitespace(parameterValue, false, true) + + // 3. If parameterValue is the empty string, then continue. + if (parameterValue.length === 0) { + continue + } + } + + // 10. If all of the following are true + // - parameterName is not the empty string + // - parameterName solely contains HTTP token code points + // - parameterValue solely contains HTTP quoted-string token code points + // - mimeType’s parameters[parameterName] does not exist + // then set mimeType’s parameters[parameterName] to parameterValue. + if ( + parameterName.length !== 0 && + HTTP_TOKEN_CODEPOINTS.test(parameterName) && + (parameterValue.length === 0 || HTTP_QUOTED_STRING_TOKENS.test(parameterValue)) && + !mimeType.parameters.has(parameterName) + ) { + mimeType.parameters.set(parameterName, parameterValue) + } + } + + // 12. Return mimeType. + return mimeType +} + +// https://infra.spec.whatwg.org/#forgiving-base64-decode +/** @param {string} data */ +function forgivingBase64 (data) { + // 1. Remove all ASCII whitespace from data. + data = data.replace(/[\u0009\u000A\u000C\u000D\u0020]/g, '') // eslint-disable-line + + // 2. If data’s code point length divides by 4 leaving + // no remainder, then: + if (data.length % 4 === 0) { + // 1. If data ends with one or two U+003D (=) code points, + // then remove them from data. + data = data.replace(/=?=$/, '') + } + + // 3. If data’s code point length divides by 4 leaving + // a remainder of 1, then return failure. + if (data.length % 4 === 1) { + return 'failure' + } + + // 4. If data contains a code point that is not one of + // U+002B (+) + // U+002F (/) + // ASCII alphanumeric + // then return failure. + if (/[^+/0-9A-Za-z]/.test(data)) { + return 'failure' + } + + const binary = atob(data) + const bytes = new Uint8Array(binary.length) + + for (let byte = 0; byte < binary.length; byte++) { + bytes[byte] = binary.charCodeAt(byte) + } + + return bytes +} + +// https://fetch.spec.whatwg.org/#collect-an-http-quoted-string +// tests: https://fetch.spec.whatwg.org/#example-http-quoted-string +/** + * @param {string} input + * @param {{ position: number }} position + * @param {boolean?} extractValue + */ +function collectAnHTTPQuotedString (input, position, extractValue) { + // 1. Let positionStart be position. + const positionStart = position.position + + // 2. Let value be the empty string. + let value = '' + + // 3. Assert: the code point at position within input + // is U+0022 ("). + assert(input[position.position] === '"') + + // 4. Advance position by 1. + position.position++ + + // 5. While true: + while (true) { + // 1. Append the result of collecting a sequence of code points + // that are not U+0022 (") or U+005C (\) from input, given + // position, to value. + value += collectASequenceOfCodePoints( + (char) => char !== '"' && char !== '\\', + input, + position + ) + + // 2. If position is past the end of input, then break. + if (position.position >= input.length) { + break + } + + // 3. Let quoteOrBackslash be the code point at position within + // input. + const quoteOrBackslash = input[position.position] + + // 4. Advance position by 1. + position.position++ + + // 5. If quoteOrBackslash is U+005C (\), then: + if (quoteOrBackslash === '\\') { + // 1. If position is past the end of input, then append + // U+005C (\) to value and break. + if (position.position >= input.length) { + value += '\\' + break + } + + // 2. Append the code point at position within input to value. + value += input[position.position] + + // 3. Advance position by 1. + position.position++ + + // 6. Otherwise: + } else { + // 1. Assert: quoteOrBackslash is U+0022 ("). + assert(quoteOrBackslash === '"') + + // 2. Break. + break + } + } + + // 6. If the extract-value flag is set, then return value. + if (extractValue) { + return value + } + + // 7. Return the code points from positionStart to position, + // inclusive, within input. + return input.slice(positionStart, position.position) +} + +/** + * @see https://mimesniff.spec.whatwg.org/#serialize-a-mime-type + */ +function serializeAMimeType (mimeType) { + assert(mimeType !== 'failure') + const { parameters, essence } = mimeType + + // 1. Let serialization be the concatenation of mimeType’s + // type, U+002F (/), and mimeType’s subtype. + let serialization = essence + + // 2. For each name → value of mimeType’s parameters: + for (let [name, value] of parameters.entries()) { + // 1. Append U+003B (;) to serialization. + serialization += ';' + + // 2. Append name to serialization. + serialization += name + + // 3. Append U+003D (=) to serialization. + serialization += '=' + + // 4. If value does not solely contain HTTP token code + // points or value is the empty string, then: + if (!HTTP_TOKEN_CODEPOINTS.test(value)) { + // 1. Precede each occurence of U+0022 (") or + // U+005C (\) in value with U+005C (\). + value = value.replace(/(\\|")/g, '\\$1') + + // 2. Prepend U+0022 (") to value. + value = '"' + value + + // 3. Append U+0022 (") to value. + value += '"' + } + + // 5. Append value to serialization. + serialization += value + } + + // 3. Return serialization. + return serialization +} + +/** + * @see https://fetch.spec.whatwg.org/#http-whitespace + * @param {string} char + */ +function isHTTPWhiteSpace (char) { + return char === '\r' || char === '\n' || char === '\t' || char === ' ' +} + +/** + * @see https://fetch.spec.whatwg.org/#http-whitespace + * @param {string} str + */ +function removeHTTPWhitespace (str, leading = true, trailing = true) { + let lead = 0 + let trail = str.length - 1 + + if (leading) { + for (; lead < str.length && isHTTPWhiteSpace(str[lead]); lead++); + } + + if (trailing) { + for (; trail > 0 && isHTTPWhiteSpace(str[trail]); trail--); + } + + return str.slice(lead, trail + 1) +} + +/** + * @see https://infra.spec.whatwg.org/#ascii-whitespace + * @param {string} char + */ +function isASCIIWhitespace (char) { + return char === '\r' || char === '\n' || char === '\t' || char === '\f' || char === ' ' +} + +/** + * @see https://infra.spec.whatwg.org/#strip-leading-and-trailing-ascii-whitespace + */ +function removeASCIIWhitespace (str, leading = true, trailing = true) { + let lead = 0 + let trail = str.length - 1 + + if (leading) { + for (; lead < str.length && isASCIIWhitespace(str[lead]); lead++); + } + + if (trailing) { + for (; trail > 0 && isASCIIWhitespace(str[trail]); trail--); + } + + return str.slice(lead, trail + 1) +} + +module.exports = { + dataURLProcessor, + URLSerializer, + collectASequenceOfCodePoints, + collectASequenceOfCodePointsFast, + stringPercentDecode, + parseMIMEType, + collectAnHTTPQuotedString, + serializeAMimeType +} |