src/httpDecorator.js
function stringifyParams (obj) {
    return obj ? arrayMap(objectKeys(obj).sort(), function (key) {
      var val = obj[key]

      if (angular.isArray(val)) {
        return arrayMap(val.sort(), function (val2) {
          return encodeURIComponent(key) + '=' + encodeURIComponent(val2)
        }).join('&')
      }

      return encodeURIComponent(key) + '=' + encodeURIComponent(val)
    }).join('&') : ''
  }
function stringifyParams (obj) {
    return obj ? arrayMap(objectKeys(obj).sort(), function (key) {
      var val = obj[key]

      if (angular.isArray(val)) {
        return arrayMap(val.sort(), function (val2) {
          return encodeURIComponent(key) + '=' + encodeURIComponent(val2)
        }).join('&')
      }

      return encodeURIComponent(key) + '=' + encodeURIComponent(val)
    }).join('&') : ''
  }
function stringifyParams ( obj ) { return obj ? arrayMap ( objectKeys ( obj ) . sort ( ) , function ( key ) { var val = obj [ key ] if ( angular . isArray ( val ) ) { return arrayMap ( val . sort ( ) , function ( val2 ) { return encodeURIComponent ( key ) + '=' + encodeURIComponent ( val2 ) } ) . join ( '&' ) } return encodeURIComponent ( key ) + '=' + encodeURIComponent ( val ) } ) . join ( '&' ) : '' }
Based on npm package "query-string"
Based on npm package query - string