koa-lite/lib/request.js
2013-11-28 12:47:23 -08:00

656 lines
14 KiB
JavaScript

/**
* Module dependencies.
*/
var debug = require('debug')('koa:context');
var Negotiator = require('negotiator');
var statuses = require('./status');
var qs = require('querystring');
var Stream = require('stream');
var fresh = require('fresh');
var http = require('http');
var path = require('path');
var mime = require('mime');
var basename = path.basename;
var extname = path.extname;
var url = require('url');
var parse = url.parse;
var stringify = url.format;
/**
* Prototype.
*/
module.exports = {
/**
* Return request header.
*
* @return {Object}
* @api public
*/
get header() {
return this.req.headers;
},
/**
* Get request URL.
*
* @return {String}
* @api public
*/
get url() {
return this.req.url;
},
/**
* Set request URL.
*
* @api public
*/
set url(val) {
this.req.url = val;
},
/**
* Get request method.
*
* @return {String}
* @api public
*/
get method() {
return this.req.method;
},
/**
* Set request method.
*
* @param {String} val
* @api public
*/
set method(val) {
this.req.method = val;
},
/**
* Get request pathname.
*
* @return {String}
* @api public
*/
get path() {
var c = this._pathcache = this._pathcache || {};
return c[this.url] || (c[this.url] = parse(this.url).pathname);
},
/**
* Set pathname, retaining the query-string when present.
*
* @param {String} path
* @api public
*/
set path(path) {
var url = parse(this.url);
url.pathname = path;
this.url = stringify(url);
},
/**
* Get parsed query-string.
*
* @return {Object}
* @api public
*/
get query() {
var str = this.querystring;
if (!str) return {};
var c = this._querycache = this._querycache || {};
return c[str] || (c[str] = qs.parse(str));
},
/**
* Set query-string as an object.
*
* @param {Object} obj
* @api public
*/
set query(obj) {
this.querystring = qs.stringify(obj);
},
/**
* Get query string.
*
* @return {String}
* @api public
*/
get querystring() {
var c = this._qscache = this._qscache || {};
return c[this.url] || (c[this.url] = parse(this.url).query || '');
},
/**
* Set querystring.
*
* @param {String} str
* @api public
*/
set querystring(str) {
var url = parse(this.url);
url.search = str;
this.url = stringify(url);
},
/**
* Get the search string. Same as the querystring
* except it includes the leading ?.
*
* @return {String}
* @api public
*/
get search() {
if (!this.querystring) return '';
return '?' + this.querystring;
},
/**
* Set the search string. Same as
* response.querystring= but included for ubiquity.
*
* @param {String} str
* @api public
*/
set search(str) {
this.querystring = str;
},
/**
* Parse the "Host" header field hostname
* and support X-Forwarded-Host when a
* proxy is enabled.
*
* @return {String}
* @api public
*/
get host() {
var proxy = this.app.proxy;
var host = proxy && this.get('X-Forwarded-Host');
host = host || this.get('Host');
if (!host) return;
return host.split(/\s*,\s*/)[0].split(':')[0];
},
/**
* Check if the request is fresh, aka
* Last-Modified and/or the ETag
* still match.
*
* @return {Boolean}
* @api public
*/
get fresh() {
var method = this.method;
var s = this.ctx.status;
// GET or HEAD for weak freshness validation only
if ('GET' != method && 'HEAD' != method) return false;
// 2xx or 304 as per rfc2616 14.26
if ((s >= 200 && s < 300) || 304 == s) {
return fresh(this.header, this.ctx.response.header);
}
return false;
},
/**
* Check if the request is stale, aka
* "Last-Modified" and / or the "ETag" for the
* resource has changed.
*
* @return {Boolean}
* @api public
*/
get stale() {
return !this.fresh;
},
/**
* Check if the request is idempotent.
*
* @return {Boolean}
* @api public
*/
get idempotent() {
return 'GET' == this.method
|| 'HEAD' == this.method;
},
/**
* Return the request socket.
*
* @return {Connection}
* @api public
*/
get socket() {
// TODO: TLS
return this.req.socket;
},
/**
* Return parsed Content-Length when present.
*
* @return {Number}
* @api public
*/
get length() {
var len = this.get('Content-Length');
if (null == len) return;
return ~~len;
},
/**
* Return the protocol string "http" or "https"
* when requested with TLS. When the proxy setting
* is enabled the "X-Forwarded-Proto" header
* field will be trusted. If you're running behind
* a reverse proxy that supplies https for you this
* may be enabled.
*
* @return {String}
* @api public
*/
get protocol() {
var proxy = this.app.proxy;
if (this.socket.encrypted) return 'https';
if (!proxy) return 'http';
var proto = this.get('X-Forwarded-Proto') || 'http';
return proto.split(/\s*,\s*/)[0];
},
/**
* Short-hand for:
*
* this.protocol == 'https'
*
* @return {Boolean}
* @api public
*/
get secure() {
return 'https' == this.protocol;
},
/**
* Return the remote address, or when
* `app.proxy` is `true` return
* the upstream addr.
*
* @return {String}
* @api public
*/
get ip() {
return this.ips[0] || this.socket.remoteAddress;
},
/**
* When `app.proxy` is `true`, parse
* the "X-Forwarded-For" ip address list.
*
* For example if the value were "client, proxy1, proxy2"
* you would receive the array `["client", "proxy1", "proxy2"]`
* where "proxy2" is the furthest down-stream.
*
* @return {Array}
* @api public
*/
get ips() {
var proxy = this.app.proxy;
var val = this.get('X-Forwarded-For');
return proxy && val
? val.split(/ *, */)
: [];
},
/**
* Return subdomains as an array.
*
* Subdomains are the dot-separated parts of the host before the main domain of
* the app. By default, the domain of the app is assumed to be the last two
* parts of the host. This can be changed by setting `app.subdomainOffset`.
*
* For example, if the domain is "tobi.ferrets.example.com":
* If `app.subdomainOffset` is not set, this.subdomains is `["ferrets", "tobi"]`.
* If `app.subdomainOffset` is 3, this.subdomains is `["tobi"]`.
*
* @return {Array}
* @api public
*/
get subdomains() {
var offset = this.app.subdomainOffset;
return (this.host || '')
.split('.')
.reverse()
.slice(offset);
},
/**
* Check if the given `type(s)` is acceptable, returning
* the best match when true, otherwise `undefined`, in which
* case you should respond with 406 "Not Acceptable".
*
* The `type` value may be a single mime type string
* such as "application/json", the extension name
* such as "json" or an array `["json", "html", "text/plain"]`. When a list
* or array is given the _best_ match, if any is returned.
*
* Examples:
*
* // Accept: text/html
* this.accepts('html');
* // => "html"
*
* // Accept: text/*, application/json
* this.accepts('html');
* // => "html"
* this.accepts('text/html');
* // => "text/html"
* this.accepts('json', 'text');
* // => "json"
* this.accepts('application/json');
* // => "application/json"
*
* // Accept: text/*, application/json
* this.accepts('image/png');
* this.accepts('png');
* // => undefined
*
* // Accept: text/*;q=.5, application/json
* this.accepts(['html', 'json']);
* this.accepts('html', 'json');
* // => "json"
*
* @param {String|Array} type(s)...
* @return {String|Array|Boolean}
* @api public
*/
accepts: function(types){
if (!Array.isArray(types)) types = [].slice.call(arguments);
var n = new Negotiator(this.req);
if (!types.length) return n.preferredMediaTypes();
if (!this.header.accept) return types[0];
var mimes = types.map(extToMime);
var accepts = n.preferredMediaTypes(mimes);
var first = accepts[0];
if (!first) return false;
return types[mimes.indexOf(first)];
},
/**
* Return accepted encodings or best fit based on `encodings`.
*
* Given `Accept-Encoding: gzip, deflate`
* an array sorted by quality is returned:
*
* ['gzip', 'deflate']
*
* @param {String|Array} encoding(s)...
* @return {String|Array}
* @api public
*/
acceptsEncodings: function(encodings) {
if (!Array.isArray(encodings)) encodings = [].slice.call(arguments);
var n = new Negotiator(this.req);
if (!encodings.length) return n.preferredEncodings();
return n.preferredEncodings(encodings)[0] || 'identity';
},
/**
* Return accepted charsets or best fit based on `charsets`.
*
* Given `Accept-Charset: utf-8, iso-8859-1;q=0.2, utf-7;q=0.5`
* an array sorted by quality is returned:
*
* ['utf-8', 'utf-7', 'iso-8859-1']
*
* @param {String|Array} charset(s)...
* @return {String|Array}
* @api public
*/
acceptsCharsets: function(charsets) {
if (!Array.isArray(charsets)) charsets = [].slice.call(arguments);
var n = new Negotiator(this.req);
if (!charsets.length) return n.preferredCharsets();
if (!this.header['accept-charset']) return charsets[0];
return n.preferredCharsets(charsets)[0] || false;
},
/**
* Return accepted languages or best fit based on `langs`.
*
* Given `Accept-Language: en;q=0.8, es, pt`
* an array sorted by quality is returned:
*
* ['es', 'pt', 'en']
*
* @param {String|Array} lang(s)...
* @return {Array|String}
* @api public
*/
acceptsLanguages: function(langs) {
if (!Array.isArray(langs)) langs = [].slice.call(arguments);
var n = new Negotiator(this.req);
if (!langs.length) return n.preferredLanguages();
if (!this.header['accept-language']) return langs[0];
return n.preferredLanguages(langs)[0] || false;
},
/**
* Vary on `field`.
*
* @param {String} field
* @api public
*/
vary: function(field){
this.append('Vary', field);
},
/**
* Check if the incoming request contains the "Content-Type"
* header field, and it contains any of the give mime `type`s.
* If there is no request body, `null` is returned.
* If there is no content type, `false` is returned.
* Otherwise, it returns the first `type` that matches.
*
* Examples:
*
* // With Content-Type: text/html; charset=utf-8
* this.is('html'); // => 'html'
* this.is('text/html'); // => 'text/html'
* this.is('text/*', 'application/json'); // => 'text/html'
*
* // When Content-Type is application/json
* this.is('json', 'urlencoded'); // => 'json'
* this.is('application/json'); // => 'application/json'
* this.is('html', 'application/*'); // => 'application/json'
*
* this.is('html'); // => false
*
* @param {String|Array} types...
* @return {String|false|null}
* @api public
*/
is: function(types){
// no request body
if (!(this.length || 'transfer-encoding' in this.header)) return;
var ct = this.type;
// no content-type
if (!ct) return false;
// paramless
ct = ct.split(';')[0];
if (!types) return ct;
// ensure array
if (!Array.isArray(types)) types = [].slice.call(arguments);
for (var i = 0; i < types.length; i++) {
var type = types[i];
switch (type) {
case 'urlencoded':
mt = 'application/x-www-form-urlencoded';
break;
default:
mt = ~type.indexOf('/') ? type : mime.lookup(type);
}
if (mimeMatch(mt, ct)) return ct;
}
// no matches
return false;
},
/**
* Return the request mime type void of
* parameters such as "charset".
*
* @return {String}
* @api public
*/
get type() {
var type = this.get('Content-Type');
if (!type) return;
return type.split(';')[0];
},
/**
* Return request header.
*
* The `Referrer` header field is special-cased,
* both `Referrer` and `Referer` are interchangeable.
*
* Examples:
*
* this.get('Content-Type');
* // => "text/plain"
*
* this.get('content-type');
* // => "text/plain"
*
* this.get('Something');
* // => undefined
*
* @param {String} field
* @return {String}
* @api public
*/
get: function(field){
var req = this.req;
switch (field = field.toLowerCase()) {
case 'referer':
case 'referrer':
return req.headers.referrer || req.headers.referer;
default:
return req.headers[field];
}
},
/**
* Inspect implementation.
*
* @return {Object}
* @api public
*/
inspect: function(){
return this.toJSON();
},
/**
* Return JSON representation.
*
* @return {Object}
* @api public
*/
toJSON: function(){
return {
method: this.method,
url: this.url,
header: this.header
}
}
};
/**
* Convert extnames to mime.
*
* @param {String} type
* @return {String}
* @api private
*/
function extToMime(type) {
if (~type.indexOf('/')) return type;
return mime.lookup(type);
}
/**
* Check if `exected` mime type
* matches `actual` mime type with
* wildcard support.
*
* @param {String} expected
* @param {String} actual
* @return {Boolean}
* @api private
*/
function mimeMatch(expected, actual) {
if (expected == actual) return true;
if (!~expected.indexOf('*')) return false;
actual = actual.split('/');
expected = expected.split('/');
if ('*' == expected[0] && expected[1] == actual[1]) return true;
if ('*' == expected[1] && expected[0] == actual[0]) return true;
}