Unit_AI/node_modules/undici/lib/fetch/dataURL.js
2024-06-01 16:24:36 -04:00

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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: dataURLs 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) {
const href = url.href
if (!excludeFragment) {
return href
}
const hash = href.lastIndexOf('#')
if (hash === -1) {
return href
}
return href.slice(0, hash)
}
// 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 doesnt 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
// - mimeTypes parameters[parameterName] does not exist
// then set mimeTypes 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 datas 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 datas 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 mimeTypes
// type, U+002F (/), and mimeTypes subtype.
let serialization = essence
// 2. For each name → value of mimeTypes 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
}