/*!
* express
* Copyright(c) 2009-2013 TJ Holowaychuk
* Copyright(c) 2014-2015 Douglas Christopher Wilson
* MIT Licensed
*/
'use strict';
/**
* Module dependencies.
* @api private
*/
var Buffer = require('safe-buffer').Buffer
var contentDisposition = require('content-disposition');
var contentType = require('content-type');
var deprecate = require('depd')('express');
var flatten = require('array-flatten');
var mime = require('send').mime;
var etag = require('etag');
var proxyaddr = require('proxy-addr');
var qs = require('qs');
var querystring = require('querystring');
/**
* Return strong ETag for `body`.
*
* @param {String|Buffer} body
* @param {String} [encoding]
* @return {String}
* @api private
*/
exports.etag = createETagGenerator({ weak: false })
/**
* Return weak ETag for `body`.
*
* @param {String|Buffer} body
* @param {String} [encoding]
* @return {String}
* @api private
*/
exports.wetag = createETagGenerator({ weak: true })
/**
* Check if `path` looks absolute.
*
* @param {String} path
* @return {Boolean}
* @api private
*/
exports.isAbsolute = function(path){
if ('/' === path[0]) return true;
if (':' === path[1] && ('\\' === path[2] || '/' === path[2])) return true; // Windows device path
if ('\\\\' === path.substring(0, 2)) return true; // Microsoft Azure absolute path
};
/**
* Flatten the given `arr`.
*
* @param {Array} arr
* @return {Array}
* @api private
*/
exports.flatten = deprecate.function(flatten,
'utils.flatten: use array-flatten npm module instead');
/**
* Normalize the given `type`, for example "html" becomes "text/html".
*
* @param {String} type
* @return {Object}
* @api private
*/
exports.normalizeType = function(type){
return ~type.indexOf('/')
? acceptParams(type)
: { value: mime.lookup(type), params: {} };
};
/**
* Normalize `types`, for example "html" becomes "text/html".
*
* @param {Array} types
* @return {Array}
* @api private
*/
exports.normalizeTypes = function(types){
var ret = [];
for (var i = 0; i < types.length; ++i) {
ret.push(exports.normalizeType(types[i]));
}
return ret;
};
/**
* Generate Content-Disposition header appropriate for the filename.
* non-ascii filenames are urlencoded and a filename* parameter is added
*
* @param {String} filename
* @return {String}
* @api private
*/
exports.contentDisposition = deprecate.function(contentDisposition,
'utils.contentDisposition: use content-disposition npm module instead');
/**
* Parse accept params `str` returning an
* object with `.value`, `.quality` and `.params`.
* also includes `.originalIndex` for stable sorting
*
* @param {String} str
* @param {Number} index
* @return {Object}
* @api private
*/
function acceptParams(str, index) {
var parts = str.split(/ *; */);
var ret = { value: parts[0], quality: 1, params: {}, originalIndex: index };
for (var i = 1; i < parts.length; ++i) {
var pms = parts[i].split(/ *= */);
if ('q' === pms[0]) {
ret.quality = parseFloat(pms[1]);
} else {
ret.params[pms[0]] = pms[1];
}
}
return ret;
}
/**
* Compile "etag" value to function.
*
* @param {Boolean|String|Function} val
* @return {Function}
* @api private
*/
exports.compileETag = function(val) {
var fn;
if (typeof val === 'function') {
return val;
}
switch (val) {
case true:
case 'weak':
fn = exports.wetag;
break;
case false:
break;
case 'strong':
fn = exports.etag;
break;
default:
throw new TypeError('unknown value for etag function: ' + val);
}
return fn;
}
/**
* Compile "query parser" value to function.
*
* @param {String|Function} val
* @return {Function}
* @api private
*/
exports.compileQueryParser = function compileQueryParser(val) {
var fn;
if (typeof val === 'function') {
return val;
}
switch (val) {
case true:
case 'simple':
fn = querystring.parse;
break;
case false:
fn = newObject;
break;
case 'extended':
fn = parseExtendedQueryString;
break;
default:
throw new TypeError('unknown value for query parser function: ' + val);
}
return fn;
}
/**
* Compile "proxy trust" value to function.
*
* @param {Boolean|String|Number|Array|Function} val
* @return {Function}
* @api private
*/
exports.compileTrust = function(val) {
if (typeof val === 'function') return val;
if (val === true) {
// Support plain true/false
return function(){ return true };
}
if (typeof val === 'number') {
// Support trusting hop count
return function(a, i){ return i < val };
}
if (typeof val === 'string') {
// Support comma-separated values
val = val.split(',')
.map(function (v) { return v.trim() })
}
return proxyaddr.compile(val || []);
}
/**
* Set the charset in a given Content-Type string.
*
* @param {String} type
* @param {String} charset
* @return {String}
* @api private
*/
exports.setCharset = function setCharset(type, charset) {
if (!type || !charset) {
return type;
}
// parse type
var parsed = contentType.parse(type);
// set charset
parsed.parameters.charset = charset;
// format type
return contentType.format(parsed);
};
/**
* Create an ETag generator function, generating ETags with
* the given options.
*
* @param {object} options
* @return {function}
* @private
*/
function createETagGenerator (options) {
return function generateETag (body, encoding) {
var buf = !Buffer.isBuffer(body)
? Buffer.from(body, encoding)
: body
return etag(buf, options)
}
}
/**
* Parse an extended query string with qs.
*
* @return {Object}
* @private
*/
function parseExtendedQueryString(str) {
return qs.parse(str, {
allowPrototypes: true
});
}
/**
* Return new empty object.
*
* @return {Object}
* @api private
*/
function newObject() {
return {};
}