javascript - Given an array of objects how do I sort the objects by a property in depth n -

i have array of objects wish sort grouping property data , string telling me property group by(eg: 'organization' or 'organization.name')

i need write function takes in data looks beforedata , returns afterdata

input :

beforedata = [ {'name':'john doe', 'id':1, 'organizations':[{'id':12, 'longname': 'group a'},{'id':13, 'longname': 'group b'}]}, {'name':'foobar', 'id':2, 'organizations':[{'id':13, 'longname': 'group b'},{'id':14, 'longname': 'group c'}]}, {'name':'kristine bell', 'id':3, 'organizations':[{'id':12, 'longname': 'group a'}]}, {'name':'adrian p', 'id':4, 'organizations':[{'id':12, 'longname': 'group a'}]} ] 

output:

    afterdata = [     {            'group': 'group a',          'entities':[             {'name':'adrian p', 'id':4, 'organizations':[{'id':12, 'longname': 'group a'}]},             {'name':'kristine bell', 'id':3, 'organizations':[{'id':12, 'longname': 'group a'}]},             {'name':'john doe', 'id':1, 'organizations':[{'id':12, 'longname': 'group a'},{'id':13, 'longname': 'group b'}]}]     },     {            'group': 'group b',          'entities':[             {'name':'john doe', 'id':1, 'organizations':[{'id':12, 'longname': 'group a'},{'id':13, 'longname': 'group b'}]},             {'name':'foobar', 'id':2, 'organizations':[{'id':13, 'longname': 'group b'},{'id':13, 'longname': 'group c'}]},]     },     {            'group': 'group c',          'entities':[             {'name':'foobar', 'id':2, 'organizations':[{'id':13, 'longname': 'group b'},{'id':13, 'longname': 'group c'}]},]     } ] 

how go accomplishing this? current attempts extremely bloated , take forever given large sets of data.

special kicker! : function solves issue needs able solve without knowing beforehand whether "group by property" in depth 1 or 2(eg: 'organization' or 'organization.longname').

something me:

// function performs data extraction object // first argument name of property extracted // might 1st level deep value `name` // or nested `foo.bar.baz` // in case if 1 of intermediate items array - array of // results returned function dot(name, obj) {     if (!name) {         return obj;     }      var match = name.match(/^([^.]+)(?:\.(.*))?$/),         head = match[1],         tail = match[2];      if (array.isarray(obj)) {         return obj.map(function(item) {             return dot(name, item);         });     }      if (obj === null || typeof obj != 'object') {         return null;     }      return dot(tail, obj[head]); }  // function accepts array of data , key group // result returns object keys equal group key // , values hold key function groupby(data, key) {     return data.reduce(function(result, item) {         var keys = dot(key, item);         if (!array.isarray(keys)) {             keys = [keys];         }          keys.foreach(function(key) {             if (!(key in result)) {                 result[key] = [];             }              result[key].push(item);         });          return result;     }, {}); }  console.log(groupby(beforedata, 'organizations.longname')); 

jsfiddle: http://jsfiddle.net/w8n4j/

it can reformatted other format want.

eg exact format question here tiny transformer:

function transformerexample(hash) {     var result = [];     (var key in hash) if (hash.hasownproperty(key)) {         result.push({             group: key,             entities: hash[key]         });     }      return result; } 

ps: main implementation may not handle possible errors. depending on actual requirements not hard improve it.