Printing JSON properties

I am currently trying to send a user information about a JSON object that I've recieved from an API. An example of the format is

[
{
    "lang_code":        "eng",
    "site_language":    "1",
    "name":         "English"
},
{
    "lang_code":        "afr",
    "site_language":    "1",
    "name":         "Afrikaans"
},
{
    "lang_code":        "ale",
    "site_language":    "0",
    "name":         "Aleut"
},
]

I want to be able to access the lang_code property of every single language and send it. I've tried to use

var languageCodes;
var languageResult = body.lang_code; //body is the result from a request.get({ ... })
    for(var codes in languageResult) {
        languageCodes = languageResult[codes];
    }

Object.keys does nothing, as it just sends 72 numbers to me. Any thoughts?

On a side note, I also want people to be able to type "!langages [my command] eng" for example, and it sends "English". Any way to do that?