Javascript: Altering an object where dot notation is used

Question

I'm building an Elasticsearch search interface. My method is to build the initial query object, and then alter it depending on the user input.

In the filter part of my object, I have

'filter':{  
    'and':[
        {
            'term' : {
                'terms.region.slug' : 'texas'
            }
        },
        {
        ...
        },
    ]
}

before I try to alter it, I at least see if I can access it.

console.log( filter.and[0].term.terms.region.slug );

However, I get:

Uncaught TypeError: Cannot read property 'region' of undefined

Maybe because the interpreter is expecting the dot notation to point to levels of an object, whereas this portion of the json going to ES is...erm.. not an object (although it's referencing an object?) This is where I get confused.

EDIT: For reference, this is what the terms object for a single result looks like in Elasticsearch.

enter image description here

`region` appears to be an array: `region: Array[1]` (uh, wrong error message though). — Felix Kling, Jun 17 '15 at 18:05
That because your property is called `terms.region.slug`, and not `terms`. If your property name uses `.` then you have to use the bracket notation. — Matt Burland, Jun 17 '15 at 18:06
There seems to be a discrepancy between the code and the screenshot you posted. Please clarify and provide a complete example. — Felix Kling, Jun 17 '15 at 18:08
@A.J: where in the screenshot do you see the property "terms.region"? — Felix Kling, Jun 17 '15 at 18:15

jamesblacklock · Accepted Answer · 2015-06-17T18:14:34.763

2

This is because the binding you've used (i.e., 'terms.region.slug') is incompatible with dot-notation. Use of dot-notation requires that the binding be parseable as an identifier. However, bracket notation is equivalent to dot-notation and allows any binding to be used.

console.log( filter.and[0].term['terms.region.slug'] );

edited Jun 17 '15 at 18:14

answered Jun 17 '15 at 18:09

jamesblacklock

849
8
14

Where in the screenshot do you see the property `terms.region.slug`? – Felix Kling Jun 17 '15 at 18:16
I don't; I am going off the the initial description of the object. I confess I am perplexed by the screenshot. – jamesblacklock Jun 17 '15 at 18:19
I updated the context of the screenshot. – psorensen Jun 17 '15 at 18:35
Ah, that makes more sense. :) – jamesblacklock Jun 17 '15 at 18:55

Javascript: Altering an object where dot notation is used

1 Answers1