/*!
* content-disposition
* Copyright(c) 2014-2017 Douglas Christopher Wilson
* MIT Licensed
*/
'use strict'
/**
* Module exports.
* @public
*/
module.exports = contentDisposition
module.exports.parse = parse
/**
* Module dependencies.
* @private
*/
var basename = require('path').basename
var Buffer = require('safe-buffer').Buffer
/**
* RegExp to match non attr-char, *after* encodeURIComponent (i.e. not including "%")
* @private
*/
var ENCODE_URL_ATTR_CHAR_REGEXP = /[\x00-\x20"'()*,/:;<=>?@[\\\]{}\x7f]/g // eslint-disable-line no-control-regex
/**
* RegExp to match percent encoding escape.
* @private
*/
var HEX_ESCAPE_REGEXP = /%[0-9A-Fa-f]{2}/
var HEX_ESCAPE_REPLACE_REGEXP = /%([0-9A-Fa-f]{2})/g
/**
* RegExp to match non-latin1 characters.
* @private
*/
var NON_LATIN1_REGEXP = /[^\x20-\x7e\xa0-\xff]/g
/**
* RegExp to match quoted-pair in RFC 2616
*
* quoted-pair = "\" CHAR
* CHAR = <any US-ASCII character (octets 0 - 127)>
* @private
*/
var QESC_REGEXP = /\\([\u0000-\u007f])/g // eslint-disable-line no-control-regex
/**
* RegExp to match chars that must be quoted-pair in RFC 2616
* @private
*/
var QUOTE_REGEXP = /([\\"])/g
/**
* RegExp for various RFC 2616 grammar
*
* parameter = token "=" ( token | quoted-string )
* token = 1*<any CHAR except CTLs or separators>
* separators = "(" | ")" | "<" | ">" | "@"
* | "," | ";" | ":" | "\" | <">
* | "/" | "[" | "]" | "?" | "="
* | "{" | "}" | SP | HT
* quoted-string = ( <"> *(qdtext | quoted-pair ) <"> )
* qdtext = <any TEXT except <">>
* quoted-pair = "\" CHAR
* CHAR = <any US-ASCII character (octets 0 - 127)>
* TEXT = <any OCTET except CTLs, but including LWS>
* LWS = [CRLF] 1*( SP | HT )
* CRLF = CR LF
* CR = <US-ASCII CR, carriage return (13)>
* LF = <US-ASCII LF, linefeed (10)>
* SP = <US-ASCII SP, space (32)>
* HT = <US-ASCII HT, horizontal-tab (9)>
* CTL = <any US-ASCII control character (octets 0 - 31) and DEL (127)>
* OCTET = <any 8-bit sequence of data>
* @private
*/
var PARAM_REGEXP = /;[\x09\x20]*([!#$%&'*+.0-9A-Z^_`a-z|~-]+)[\x09\x20]*=[\x09\x20]*("(?:[\x20!\x23-\x5b\x5d-\x7e\x80-\xff]|\\[\x20-\x7e])*"|[!#$%&'*+.0-9A-Z^_`a-z|~-]+)[\x09\x20]*/g // eslint-disable-line no-control-regex
var TEXT_REGEXP = /^[\x20-\x7e\x80-\xff]+$/
var TOKEN_REGEXP = /^[!#$%&'*+.0-9A-Z^_`a-z|~-]+$/
/**
* RegExp for various RFC 5987 grammar
*
* ext-value = charset "'" [ language ] "'" value-chars
* charset = "UTF-8" / "ISO-8859-1" / mime-charset
* mime-charset = 1*mime-charsetc
* mime-charsetc = ALPHA / DIGIT
* / "!" / "#" / "$" / "%" / "&"
* / "+" / "-" / "^" / "_" / "`"
* / "{" / "}" / "~"
* language = ( 2*3ALPHA [ extlang ] )
* / 4ALPHA
* / 5*8ALPHA
* extlang = *3( "-" 3ALPHA )
* value-chars = *( pct-encoded / attr-char )
* pct-encoded = "%" HEXDIG HEXDIG
* attr-char = ALPHA / DIGIT
* / "!" / "#" / "$" / "&" / "+" / "-" / "."
* / "^" / "_" / "`" / "|" / "~"
* @private
*/
var EXT_VALUE_REGEXP = /^([A-Za-z0-9!#$%&+\-^_`{}~]+)'(?:[A-Za-z]{2,3}(?:-[A-Za-z]{3}){0,3}|[A-Za-z]{4,8}|)'((?:%[0-9A-Fa-f]{2}|[A-Za-z0-9!#$&+.^_`|~-])+)$/
/**
* RegExp for various RFC 6266 grammar
*
* disposition-type = "inline" | "attachment" | disp-ext-type
* disp-ext-type = token
* disposition-parm = filename-parm | disp-ext-parm
* filename-parm = "filename" "=" value
* | "filename*" "=" ext-value
* disp-ext-parm = token "=" value
* | ext-token "=" ext-value
* ext-token = <the characters in token, followed by "*">
* @private
*/
var DISPOSITION_TYPE_REGEXP = /^([!#$%&'*+.0-9A-Z^_`a-z|~-]+)[\x09\x20]*(?:$|;)/ // eslint-disable-line no-control-regex
/**
* Create an attachment Content-Disposition header.
*
* @param {string} [filename]
* @param {object} [options]
* @param {string} [options.type=attachment]
* @param {string|boolean} [options.fallback=true]
* @return {string}
* @public
*/
function contentDisposition (filename, options) {
var opts = options || {}
// get type
var type = opts.type || 'attachment'
// get parameters
var params = createparams(filename, opts.fallback)
// format into string
return format(new ContentDisposition(type, params))
}
/**
* Create parameters object from filename and fallback.
*
* @param {string} [filename]
* @param {string|boolean} [fallback=true]
* @return {object}
* @private
*/
function createparams (filename, fallback) {
if (filename === undefined) {
return
}
var params = {}
if (typeof filename !== 'string') {
throw new TypeError('filename must be a string')
}
// fallback defaults to true
if (fallback === undefined) {
fallback = true
}
if (typeof fallback !== 'string' && typeof fallback !== 'boolean') {
throw new TypeError('fallback must be a string or boolean')
}
if (typeof fallback === 'string' && NON_LATIN1_REGEXP.test(fallback)) {
throw new TypeError('fallback must be ISO-8859-1 string')
}
// restrict to file base name
var name = basename(filename)
// determine if name is suitable for quoted string
var isQuotedString = TEXT_REGEXP.test(name)
// generate fallback name
var fallbackName = typeof fallback !== 'string'
? fallback && getlatin1(name)
: basename(fallback)
var hasFallback = typeof fallbackName === 'string' && fallbackName !== name
// set extended filename parameter
if (hasFallback || !isQuotedString || HEX_ESCAPE_REGEXP.test(name)) {
params['filename*'] = name
}
// set filename parameter
if (isQuotedString || hasFallback) {
params.filename = hasFallback
? fallbackName
: name
}
return params
}
/**
* Format object to Content-Disposition header.
*
* @param {object} obj
* @param {string} obj.type
* @param {object} [obj.parameters]
* @return {string}
* @private
*/
function format (obj) {
var parameters = obj.parameters
var type = obj.type
if (!type || typeof type !== 'string' || !TOKEN_REGEXP.test(type)) {
throw new TypeError('invalid type')
}
// start with normalized type
var string = String(type).toLowerCase()
// append parameters
if (parameters && typeof parameters === 'object') {
var param
var params = Object.keys(parameters).sort()
for (var i = 0; i < params.length; i++) {
param = params[i]
var val = param.substr(-1) === '*'
? ustring(parameters[param])
: qstring(parameters[param])
string += '; ' + param + '=' + val
}
}
return string
}
/**
* Decode a RFC 6987 field value (gracefully).
*
* @param {string} str
* @return {string}
* @private
*/
function decodefield (str) {
var match = EXT_VALUE_REGEXP.exec(str)
if (!match) {
throw new TypeError('invalid extended field value')
}
var charset = match[1].toLowerCase()
var encoded = match[2]
var value
// to binary string
var binary = encoded.replace(HEX_ESCAPE_REPLACE_REGEXP, pdecode)
switch (charset) {
case 'iso-8859-1':
value = getlatin1(binary)
break
case 'utf-8':
value = Buffer.from(binary, 'binary').toString('utf8')
break
default:
throw new TypeError('unsupported charset in extended field')
}
return value
}
/**
* Get ISO-8859-1 version of string.
*
* @param {string} val
* @return {string}
* @private
*/
function getlatin1 (val) {
// simple Unicode -> ISO-8859-1 transformation
return String(val).replace(NON_LATIN1_REGEXP, '?')
}
/**
* Parse Content-Disposition header string.
*
* @param {string} string
* @return {object}
* @public
*/
function parse (string) {
if (!string || typeof string !== 'string') {
throw new TypeError('argument string is required')
}
var match = DISPOSITION_TYPE_REGEXP.exec(string)
if (!match) {
throw new TypeError('invalid type format')
}
// normalize type
var index = match[0].length
var type = match[1].toLowerCase()
var key
var names = []
var params = {}
var value
// calculate index to start at
index = PARAM_REGEXP.lastIndex = match[0].substr(-1) === ';'
? index - 1
: index
// match parameters
while ((match = PARAM_REGEXP.exec(string))) {
if (match.index !== index) {
throw new TypeError('invalid parameter format')
}
index += match[0].length
key = match[1].toLowerCase()
value = match[2]
if (names.indexOf(key) !== -1) {
throw new TypeError('invalid duplicate parameter')
}
names.push(key)
if (key.indexOf('*') + 1 === key.length) {
// decode extended value
key = key.slice(0, -1)
value = decodefield(value)
// overwrite existing value
params[key] = value
continue
}
if (typeof params[key] === 'string') {
continue
}
if (value[0] === '"') {
// remove quotes and escapes
value = value
.substr(1, value.length - 2)
.replace(QESC_REGEXP, '$1')
}
params[key] = value
}
if (index !== -1 && index !== string.length) {
throw new TypeError('invalid parameter format')
}
return new ContentDisposition(type, params)
}
/**
* Percent decode a single character.
*
* @param {string} str
* @param {string} hex
* @return {string}
* @private
*/
function pdecode (str, hex) {
return String.fromCharCode(parseInt(hex, 16))
}
/**
* Percent encode a single character.
*
* @param {string} char
* @return {string}
* @private
*/
function pencode (char) {
return '%' + String(char)
.charCodeAt(0)
.toString(16)
.toUpperCase()
}
/**
* Quote a string for HTTP.
*
* @param {string} val
* @return {string}
* @private
*/
function qstring (val) {
var str = String(val)
return '"' + str.replace(QUOTE_REGEXP, '\\$1') + '"'
}
/**
* Encode a Unicode string for HTTP (RFC 5987).
*
* @param {string} val
* @return {string}
* @private
*/
function ustring (val) {
var str = String(val)
// percent encode as UTF-8
var encoded = encodeURIComponent(str)
.replace(ENCODE_URL_ATTR_CHAR_REGEXP, pencode)
return 'UTF-8\'\'' + encoded
}
/**
* Class for parsed Content-Disposition header for v8 optimization
*
* @public
* @param {string} type
* @param {object} parameters
* @constructor
*/
function ContentDisposition (type, parameters) {
this.type = type
this.parameters = parameters
}