如何获得两个JavaScript对象图之间的差异列表?

这是我的问题的一个局部的、朴素的解决方案——我会在进一步发展的过程中更新它。

function findDifferences(objectA, objectB) {
   var propertyChanges = [];
   var objectGraphPath = ["this"];
   (function(a, b) {
      if(a.constructor == Array) {
         // BIG assumptions here: That both arrays are same length, that
         // the members of those arrays are _essentially_ the same, and 
         // that those array members are in the same order...
         for(var i = 0; i < a.length; i++) {
            objectGraphPath.push("[" + i.toString() + "]");
            arguments.callee(a[i], b[i]);
            objectGraphPath.pop();
         }
      } else if(a.constructor == Object || (a.constructor != Number && 
                a.constructor != String && a.constructor != Date && 
                a.constructor != RegExp && a.constructor != Function &&
                a.constructor != Boolean)) {
         // we can safely assume that the objects have the 
         // same property lists, else why compare them?
         for(var property in a) {
            objectGraphPath.push(("." + property));
            if(a[property].constructor != Function) {
               arguments.callee(a[property], b[property]);
            }
            objectGraphPath.pop();
         }
      } else if(a.constructor != Function) { // filter out functions
         if(a != b) {
            propertyChanges.push({ "Property": objectGraphPath.join(""), "ObjectA": a, "ObjectB": b });
         }
      }
   })(objectA, objectB);
   return propertyChanges;
}

下面是一个如何使用它以及它将提供的数据的示例(请原谅这个冗长的示例,但我想使用一些相对不琐碎的东西):

var person1 = { 
   FirstName : "John", 
   LastName : "Doh", 
   Age : 30, 
   EMailAddresses : [
      "john.doe@gmail.com", 
      "jd@initials.com"
   ], 
   Children : [ 
      { 
         FirstName : "Sara", 
         LastName : "Doe", 
         Age : 2 
      }, { 
         FirstName : "Beth", 
         LastName : "Doe", 
         Age : 5 
      } 
   ] 
};

var person2 = { 
   FirstName : "John", 
   LastName : "Doe", 
   Age : 33, 
   EMailAddresses : [
      "john.doe@gmail.com", 
      "jdoe@hotmail.com"
   ], 
   Children : [ 
      { 
         FirstName : "Sara", 
         LastName : "Doe", 
         Age : 3 
      }, { 
         FirstName : "Bethany", 
         LastName : "Doe", 
         Age : 5 
      } 
   ] 
};

var differences = findDifferences(person1, person2);

differences 如果将数组序列化为JSON,则该数组的外观如下:

[
   {
      "Property":"this.LastName", 
      "ObjectA":"Doh", 
      "ObjectB":"Doe"
   }, {
      "Property":"this.Age", 
      "ObjectA":30, 
      "ObjectB":33
   }, {
      "Property":"this.EMailAddresses[1]", 
      "ObjectA":"jd@initials.com", 
      "ObjectB":"jdoe@hotmail.com"
   }, {
      "Property":"this.Children[0].Age", 
      "ObjectA":2, 
      "ObjectB":3
   }, {
      "Property":"this.Children[1].FirstName", 
      "ObjectA":"Beth", 
      "ObjectB":"Bethany"
   }
]

this 在 Property 值是指被比较对象的根。因此,这一解决方案还不成熟 确切地 我所需要的,但它非常接近。

希望这对其他人有用,如果你有任何改进建议,我洗耳恭听;我昨晚很晚才写这封信(即今天凌晨),可能有些事情我完全忽略了。

谢谢

在回顾了现有的答案之后,我注意到 https://github.com/flitbit/diff

从我的研究来看,这个库在积极开发、贡献和解决对象扩散挑战方面似乎是最好的。这对于在服务器端创建diff并只向客户端传递更改的位非常方便。

有一个 objectDiff library 这让你可以这么做。在其上 demo page

你也可以试试rus diff https://github.com/mirek/node-rus-diff 这将生成MongoDB兼容(重命名/取消设置/设置)差异。

var person1 = {
  FirstName: "John",
  LastName: "Doh",
  Age: 30,
  EMailAddresses: ["john.doe@gmail.com", "jd@initials.com"],
  Children: [
    {
      FirstName: "Sara",
      LastName: "Doe",
      Age: 2
    }, {
      FirstName: "Beth",
      LastName: "Doe",
      Age: 5
    }
  ]
};

var person2 = {
  FirstName: "John",
  LastName: "Doe",
  Age: 33,
  EMailAddresses: ["john.doe@gmail.com", "jdoe@hotmail.com"],
  Children: [
    {
      FirstName: "Sara",
      LastName: "Doe",
      Age: 3
    }, {
      FirstName: "Bethany",
      LastName: "Doe",
      Age: 5
    }
  ]
};

var rusDiff = require('rus-diff').rusDiff

console.log(rusDiff(person1, person2))

它生成一个集合列表:

{ '$set': 
   { 'Age': 33,
     'Children.0.Age': 3,
     'Children.1.FirstName': 'Bethany',
     'EMailAddresses.1': 'jdoe@hotmail.com',
     'LastName': 'Doe' } }

解决方案1

解决方案2

这可以通过一些修改实现您想要的功能,它是函数u.isEqual的修改版本( http://documentcloud.github.com/underscore/ )。请随时提出修改建议!我写它是为了找出两个对象之间的第一个差异出现在哪里。

// Given two objects find the first key or value not matching, algorithm is a
// inspired by of _.isEqual.
function diffObjects(a, b) {
  console.info("---> diffObjects", {"a": a, "b": b});
  // Check object identity.
  if (a === b) return true;
  // Different types?
  var atype = typeof(a), btype = typeof(b);
  if (atype != btype) {
    console.info("Type mismatch:", {"a": a, "b": b});
    return false;
  };
  // Basic equality test (watch out for coercions).
  if (a == b) return true;
  // One is falsy and the other truthy.
  if ((!a && b) || (a && !b)) {
    console.info("One is falsy and the other truthy:", {"a": a, "b": b});
    return false;
  }
  // Unwrap any wrapped objects.
  if (a._chain) a = a._wrapped;
  if (b._chain) b = b._wrapped;
  // One of them implements an isEqual()?
  if (a.isEqual) return a.isEqual(b);
  // Check dates' integer values.
  if (_.isDate(a) && _.isDate(b)) return a.getTime() === b.getTime();
  // Both are NaN?
  if (_.isNaN(a) && _.isNaN(b)) {
    console.info("Both are NaN?:", {"a": a, "b": b});
    return false;
  }
  // Compare regular expressions.
  if (_.isRegExp(a) && _.isRegExp(b))
    return a.source     === b.source &&
           a.global     === b.global &&
           a.ignoreCase === b.ignoreCase &&
           a.multiline  === b.multiline;
  // If a is not an object by this point, we can't handle it.
  if (atype !== 'object') {
    console.info("a is not an object:", {"a": a});
    return false;
  }
  // Check for different array lengths before comparing contents.
  if (a.length && (a.length !== b.length)) {
    console.info("Arrays are of different length:", {"a": a, "b": b});
    return false;
  }
  // Nothing else worked, deep compare the contents.
  var aKeys = _.keys(a), bKeys = _.keys(b);
  // Different object sizes?
  if (aKeys.length != bKeys.length) {
    console.info("Different object sizes:", {"a": a, "b": b});
    return false;
  }
  // Recursive comparison of contents.
  for (var key in a) if (!(key in b) || !diffObjects(a[key], b[key])) return false;
  return true;
};

https://github.com/NV/objectDiff.js

高兴

我最近写了一个模块来实现这一点,因为我不满意我发现的众多不同的模块(我列出了一堆最流行的模块,以及为什么它们在我的模块自述中不被接受)。它叫 odiff : https://github.com/Tixit/odiff

var a = [{a:1,b:2,c:3},              {x:1,y: 2, z:3},              {w:9,q:8,r:7}]
var b = [{a:1,b:2,c:3},{t:4,y:5,u:6},{x:1,y:'3',z:3},{t:9,y:9,u:9},{w:9,q:8,r:7}]

var diffs = odiff(a,b)

/* diffs now contains:
[{type: 'add', path:[], index: 2, vals: [{t:9,y:9,u:9}]},
 {type: 'set', path:[1,'y'], val: '3'},
 {type: 'add', path:[], index: 1, vals: [{t:4,y:5,u:6}]}
]
*/

我找到的库都不够,所以我写了自己的AngularJS工厂。它以两种方式比较对象,只返回同一结构中的差异。

/**
 * Diff
 * Original author: Danny Coulombe
 * Creation date: 2016-05-18
 * 
 * Work with objects to find their differences.
 */
controllers.factory('diff', [function() {

    var factory = {

        /**
         * Compare the original object with the modified one and return their differences.
         * 
         * @param original: Object
         * @param modified: Object
         * 
         * @return Object
         */
        getDifferences: function(original, modified) {

            var type = modified.constructor === Array ? [] : {};
            var result = angular.copy(type);
            var comparisons = [[original, modified, 1], [modified, original, 0]];

            comparisons.forEach(function(comparison) {

                angular.forEach(comparison[0], function(value, key) {

                    if(result[key] === undefined) {

                        if(comparison[1][key] !== undefined && value !==    null && comparison[1][key] !== null && [Object, Array].indexOf(comparison[1][key].constructor) !== -1) {

                            result[key] = factory.getDifferences(value, comparison[1][key]);
                        }
                        else if(comparison[1][key] !== value) {

                            result[key] = comparison[comparison[2]][key];
                        }

                        if(angular.equals(type, result[key])
                        || result[key] === undefined
                        || (
                            comparison[0][key] !== undefined
                            && result[key] !== null
                            && comparison[0][key] !== null
                            && comparison[0][key].length === comparison[1][key].length
                            && result[key].length === 0
                        )) {
                            delete result[key];
                        }
                    }
                });
            });

            return result;
        }
    };

    return factory;
}]);

var first = [ 1, 2, 3, 4, 5 ];
var second = [ 4, 5, 6 ];

var difference = first.filter(x => second.indexOf(x) === -1);
console.log(difference);