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Diffstat (limited to 'web-ui/app/js/helpers/contenttype.js')
| -rw-r--r-- | web-ui/app/js/helpers/contenttype.js | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/web-ui/app/js/helpers/contenttype.js b/web-ui/app/js/helpers/contenttype.js new file mode 100644 index 00000000..a1e5361a --- /dev/null +++ b/web-ui/app/js/helpers/contenttype.js @@ -0,0 +1,184 @@ +/* + * Copyright (c) 2014 ThoughtWorks, Inc. + * + * Pixelated is free software: you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * Pixelated is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with Pixelated. If not, see <http://www.gnu.org/licenses/>. + */ + +/* jshint curly: false */ +define([], function () { + 'use strict'; + var exports = {}; + + // Licence: PUBLIC DOMAIN <http://unlicense.org/> + // Author: Austin Wright <http://github.com/Acubed> + + function MediaType(s, p){ + this.type = ''; + this.params = {}; + var c, i, n; + if(typeof s==='string'){ + c = splitQuotedString(s); + this.type = c.shift(); + for(i=0; i<c.length; i++){ + this.parseParameter(c[i]); + } + }else if(s instanceof MediaType){ + this.type = s.type; + this.q = s.q; + for(n in s.params) this.params[n]=s.params[n]; + } + if(typeof p==='string'){ + c = splitQuotedString(p); + for(i=0; i<c.length; i++){ + this.parseParameter(c[i]); + } + }else if(typeof p==='object'){ + for(n in p) this.params[n]=p[n]; + } + } + MediaType.prototype.parseParameter = function parseParameter(s){ + var param = s.split('=',1); + var name = param[0].trim(); + var value = s.substr(param[0].length+1).trim(); + if(!value || !name) return; + if(name==='q' && this.q===undefined){ + this.q=parseFloat(value); + }else{ + if(value[0]==='"' && value[value.length-1]==='"'){ + value = value.substr(1, value.length-2); + value = value.replace(/\\(.)/g, function(a,b){return b;}); + } + this.params[name]=value; + } + }; + MediaType.prototype.toString = function toString(){ + var str = this.type + ';q='+this.q; + for(var n in this.params){ + str += ';'+n+'='; + if(this.params[n].match(/["=;<>\[\]\(\) ,\-]/)){ + str += '"' + this.params[n].replace(/["\\]/g, function(a){return '\\'+a;}) + '"'; + }else{ + str += this.params[n]; + } + } + return str; + }; + exports.MediaType = MediaType; + + // Split a string by character, but ignore quoted parts and backslash-escaped characters + function splitQuotedString(str, delim, quote){ + delim = delim || ';'; + quote = quote || '"'; + var res = []; + var start = 0; + var offset = 0; + function findNextChar(v, c, i, a){ + var p = str.indexOf(c, offset+1); + return (p<0)?v:Math.min(p,v); + } + while(offset>=0){ + offset = [delim,quote].reduce(findNextChar, 1/0); + if(offset===1/0) break; + switch(str[offset]){ + case quote: + // Skip to end of quoted string + while(1){ + offset=str.indexOf(quote, offset+1); + if(offset<0) break; + if(str[offset-1]==='\\') continue; + break; + } + continue; + case delim: + res.push(str.substr(start, offset-start).trim()); + start = ++offset; + break; + } + } + res.push(str.substr(start).trim()); + return res; + } + exports.splitQuotedString = splitQuotedString; + + // Split a list of content types found in an Accept header + // Maybe use it like: splitContentTypes(request.headers.accept).map(parseMedia) + function splitContentTypes(str){ + return splitQuotedString(str, ','); + } + exports.splitContentTypes = splitContentTypes; + + function parseMedia(str){ + var o = new MediaType(str); + if(o.q===undefined) o.q=1; + return o; + } + exports.parseMedia = parseMedia; + + // Pick an ideal representation to send given a list of representations to choose from and the client-preferred list + function select(reps, accept){ + var cr = {q:0}; + var ca = {q:0}; + var cq = 0; + for(var i=0; i<reps.length; i++){ + var r = reps[i]; + var rq = r.q || 1; + for(var j=0; j<accept.length; j++){ + var a=accept[j]; + var aq = a.q || 1; + var cmp = mediaCmp(a, r); + if(cmp!==null && cmp>=0){ + if(aq*rq>cq){ + ca = a; + cr = r; + cq = ca.q*cr.q; + if(cq===1 && cr.type) return cr; + } + } + } + } + return cr.type&&cr; + } + exports.select = select; + + // Determine if one media type is a subset of another + // If a is a superset of b (b is smaller than a), return 1 + // If b is a superset of a, return -1 + // If they are the exact same, return 0 + // If they are disjoint, return null + function mediaCmp(a, b){ + if(a.type==='*/*' && b.type!=='*/*') return 1; + else if(a.type!=='*/*' && b.type==='*/*') return -1; + var ac = (a.type||'').split('/'); + var bc = (b.type||'').split('/'); + if(ac[0]==='*' && bc[0]!=='*') return 1; + if(ac[0]!=='*' && bc[0]==='*') return -1; + if(a.type!==b.type) return null; + var ap = a.params || {}; + var bp = b.params || {}; + var ak = Object.keys(ap); + var bk = Object.keys(bp); + if(ak.length < bk.length) return 1; + if(ak.length > bk.length) return -1; + var k = ak.concat(bk).sort(); + var dir = 0; + for(var n in ap){ + if(ap[n] && !bp[n]){ if(dir<0) return null; else dir=1; } + if(!ap[n] && bp[n]){ if(dir>0) return null; else dir=-1; } + } + return dir; + } + exports.mediaCmp = mediaCmp; + + return exports; +}); |