Check if value for a key exists in an array of objects.

findValueInArrayOfObjects.js

var arrayOfObjects = [{key1: 'foo1', key2: 'bar1'}, {key1: 'foo2', key2: 'bar2'}];

var keyNameToCheck = "key1";
var valueToFind = 'foo1';

function doesArrayOfObjectsContainValueForKey(array, keyName, value){
  var res = array.filter(function(obj){
    return obj[keyName] === value;
  });
  return res.length === 0 ? false : true;
}

//usage
doesArrayOfObjectsContainValueForKey(arrayOfObjects, keyNameToCheck, valueToFind);