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angular, strip unused data before doing a lodash _.isEqual

So I have am trying to compare 2 objects using lodash's _.isEqual method, I have pretty straight forward function that checks like so
function findMatchingQuery(savedSearch) {
if (_.isEqual(savedSearch.data.document.query, $scope.searchResults.minify())) {
return true;
}
}
The data has changed a bit and I need to pull out a piece of data inside before I do a compare.
So the each of those objects has this format -
{
"name": "item name",
"showMore": boolean,
"filters": []
}
And what I would like to do is strip out the showMore node. I tried to add the some vars using _.remove, however it seems this does not work because remove is looking for a key and value.
var modifiedSavedSearch = _.remove(savedSearch.data.document.query, { "showMore" });
var modifiedCurrentSearch = _.remove($scope.searchResults.minify(), { "showMore" });
Is there a simple way to strip away those parts of the object before running the _.isEqual on them? Doesn't have to be lodash. Thanks!

You can delete the attribute, like:
delete savedSearch.data.document.query.showMore
You can use _.omit to remove it, or you can use _.pick to pick the rest of the attributes

Yeah, omit should do what you are looking for:
var modifiedSavedSearch = _.omit(savedSearch.data.document.query, { "showMore" });

If you want to get rid of it completely, you can do the following:
// assuming this is your variable
var myVar = {
"name": "item name",
"showMore": boolean,
"filters": []
};
// delete the unwanted property
delete myVar.showMore;

How do I find a JSON object using a nested expression?

From the example JSON below, I would like to return the target.id value of an object where the source.id == 'x'.
So where source.id == 'startId' return target.id == '3eecd840-e6a8-423c-a892-7df9646fde5d'.
{
"line":[
{
"type":"link",
"source":{
"id":"startId",
"port":"out"
},
"target":{
"id":"3eecd840-e6a8-423c-a892-7df9646fde5d",
"port":"in"
},
"id":"87d88a26-3a28-4db0-8016-71c1c4665f14"
},
{
"type":"link",
"source":{
"id":"3eecd840-e6a8-423c-a892-7df9646fde5d",
"port":"outYes"
},
"target":{
"id":"49940c02-70f2-4c53-ab50-9cbf96903600",
"port":"in"
},
"id":"9f8c365e-9ca7-440f-a722-c4f340782c0c"
}
]
}
I've tried JSONPath, but I cannot work out the expression to use. $.line[*].source.id gives me a list of source id's and $.line[?(#.source.id=='startId')] returns an error.
I also understand that I could iterate through each object in code, but It wouldn't be very efficient if I have tens or hundreds of 'lines' to work through. If possible I would like a more 'direct' path to the object.
I'm using javascript to code the rest of the app, so javascript examples would be helpful (with or without JSONPath).

If you're getting json as string, then use var json = JSON.parse(jsonStr). Then you can do it with Array.filter
var result = json.line.filter(function(obj){
return obj.source.id == "startId"
});
Then you could get the values like this
var ids = result.map(function(o){ return o.target.id });

Is there a way to iterate and display the list of key value pairs of json using Handlebar.js

As Iam new to javascript, I found handleBar.js can be used to template with dynamic data.
I worked on a sample which worked fine and the json structure was simple and straight forward.
(function()
{
var wtsource = $("#some-template").html();
var wtTemplate = Handlebars.compile(wtsource);
var data = { users: [
{url: "index.html", name: "Home" },
{url: "aboutus.html", name: "About Us"},
{url: "contact.html", name: "Contact"}
]};
Handlebars.registerHelper('iter', function(context, options) {
var fn = options.fn, inverse = options.inverse;
var ret = "";
if(context && context.length > 0) {
for(var i=0, j=context.length; i<j; i++) {
ret = ret + fn($.extend({}, context[i], { i: i, iPlus1: i + 1 }));
}
} else {
ret = inverse(this);
}
return ret;
});
var temp=wtTemplate(data);
$("#content").html(temp);
})();
<script id="some-template" type="text/x-handlebars-template">
{{#iter users}}
<li>
{{name}}
</li>
{{/iter}}
</script>
How to iterate a json with the below structure ? Please do suggest the possible way for iterating and creating the template for the below json structure
var newData = { "NEARBY_LIST": {
"100": {
"RestaurantID": 100,
"ParentRestaurantID": 0,
"RestaurantName": "Chennai Tiffin",
"listTime": [{
"startTime": "10:00",
"closeTime": "23:30"
} ]
},
"101": {
"RestaurantID": 101,
"ParentRestaurantID": 0,
"RestaurantName": "Biriyani Factory",
"listTime": [{
"startTime": "11:00",
"closeTime": "22:00"
}]
}
}
};

Accessing the properties of an object has nothing to do with Handlebars. If you dealing with JSON and you wish to access it in general bracket or dot notation, you must first parse the JSON into a JavaScript object using the JSON.parse() function.
After this is done, you may access the properties as follows.
var property = newData['NEARBY_LIST']['100'].RestaurantName; // "Chennai Tiffin"
Here is a fiddle to illustrate.
http://jsfiddle.net/qzm0cygu/2/

I'm not entirely sure what you mean, but if your question is how you can use/read the data in newData, try this:
newData = JSON.parse(newData); //parses the JSON into a JavaScript object
Then access the object like so:
newData.NEARBY_LIST //the object containing the array
newData.NEARBY_LIST[0] //the first item (key "100")
newData.NEARBY_LIST[1] //the second item (key "101")
newData.NEARBY_LIST[0][0] //the first field of the first item (key "RestaurantID", value "100")
newData.NEARBY_LIST[0][2] //the third field of the first item (key "RestaurantName", value "Chennai Tiffin")
newData.NEARBY_LIST[0][3][0] //the first field of the fourth field of the first item (key "startTime", value "11:00")
I hope this was what you were looking for.
EDIT: as Siddharth points out, the above structure does assume you have arrays. If you are not using arrays you can access the properties by using their names as if they're in an associative array (e.g. newData["NEARBY_LIST"]["100"]. The reason I say "properties" and "as if" is because technically JavaScript doesn't support associative arrays. Because they are technically properties you may also access them like newData.NEARBY_LIST (but I don't recommend that in this case as a property name may not start with a number, so you would have to use a mix of the different notations).
On that note, I would recommend using arrays because it makes so many things easier (length checks, for example), and there are practically no downsides.
EDIT2: also, I strongly recommend using the same camelcasing conventions throughout your code. The way you currently have it (with half your properties/variables starting with capitals (e.g. "RestaurantName", "RestaurantID") and the other half being in lowerCamelCase (e.g. "listTime", "startTime")) is just asking for people (you or colleagues) to make mistakes.

accessing field value in array of objects in javascript

I need to access an element with a certain field value for the cdOption field in this array of objects of type possibleOptions:
[Object { cdOption="OPT001", description="Description 1", type="STRING"},
Object { cdOption="OPT002", description="Description 2", type="STRING"},
Object { cdOption="OPT003", description="Description 3", type="STRING"}]
The field value I'm looking for is extracted from antoher object in an array and so I'm alreay in a $.each cycle.
Can I avoid entering another cycle in order to loop the possibleOptions object and look for the specified field value?
I've tried with
possibleOptions[option.cdOpzione] but it doesn't work, is there a way to do this? I know I'm missing something.
current $.each code:
$.each(oldOptions, function(key, option) {
$.each(possibleOptions, function(key, possibleOption) {
if (option.cdOption === possibleOptions.cdOption) {
console.log(option.cdOption);
console.log(possibleOption.description);
}
});
});

In a generic way, you can't avoid the extra cycle. There may be particular solutions though, depending on your circumstances.
Solution 1
You could avoid it if you restructure your data, to have possibleOptions be an object with the values in cdOption as keys and an object with description and type as value.
Example:
var possibleOptions = {
'OPT001' : { description:"Description 1", type:"STRING" },
'OPT002' : { description:"Description 2", type:"STRING" },
'OPT003' : { description:"Description 3", type:"STRING" }
};
var val = 'OPT002';
console.log(possibleOptions[val]);
Solution 2
Another thing you could do if the cdOption is always of the form OPT-index- where -index- is 1+ the index in the array is to parse the value you're looking for, extract the -index-, parseInt and subtract one.
Example:
var val = 'OPT002';
var index = parseInt(val.substring(3))-1;
console.log(possibleOptions[index]);
Demo for both: http://jsbin.com/opojozE/1/edit

Array.filter can return an array of the elements matching a conditon. e.g. if you want to find the object (or objects) with cdOption == "OPT002", you could say:
var matches = possibleOptions.filter(
function( element ) {
return ( "OPT002" == element.cdOption );
}
);
and matches will contain:
[
{ cdOption="OPT002", description="Description 2", type="STRING"}
]
if you're just looking for one match:
var myOption = (matches.length > 0) ? matches[0] : null;
If you need to support older browsers that lack Array.filter, see Array filter method at MDN for a way to add it.

JavaScript JSON parse by a given key without looping

Given a JSON string as this:
{
"__ENTITIES": [
{
"__KEY": "196",
"__STAMP": 1,
"ID": 196,
"firstName": "a",
"middleName": "b",
"lastName": "c",
"ContactType": {},
"addressCollection": {
"__deferred": {
"uri": "/rest/Contact(196)/addressCollection?$expand=addressCollection"
}
},
"__ERROR": [
{
"message": "Cannot save related entity of attribute \"ContactType\" for the entity of datastore class \"Contact\"",
"componentSignature": "dbmg",
"errCode": 1537
}
]
}
]
}
Is there a method to get just the __ERROR record, I know I can use
var mydata = json.parse(mydata) and then find it from the mydata object. But I was hoping there was a method to only return the ERROR field something like
json.parse(mydata, "__ERROR") and that gets only the information in the __ERROR field without turning the whole JSON string into an object

"Is there a method to get just the __ERROR record, I know I can use var mydata = json.parse(mydata) ... But I was hoping there was ... something like json.parse(mydata, "__ERROR")"
There may be libraries that do this, but nothing built in. You need to write code that targets the data you want.
The closest you'll get will be to pass a reviver function to JSON.parse.
var errors = [];
var mydata = JSON.parse(mydata, function(key, val) {
if (key === "__ERROR")
errors.push(val);
return val
});

without turning the whole json string into an object
That's hardly possible, you would need some kind of lazy evaluation for that which is not suitable with JS. Also, you would need to write your own parser for that which would be reasonable slower than native JSON.parse.
Is there a method to get just the __ERROR record
Not that I know. Also, this is an unusual task to walk the whole object tree looking for the first property with that name. Better access __ENTITIES[0].__ERROR[0] explicitly.

If such a function existed, it would have to parse the whole thing anyway, to find the key you're looking for.
Just parse it first, then get the key you want:
var mydata = JSON.parse(mydata);
var errorObj = mydata.__ENTITIES[0].__ERROR[0];
If you want, you may create your own function:
function parseAndExtract(json, key) {
var parsed = JSON.parse(json);
return parsed[key];
}