Accessing the quota service in Node.js

You're viewing Apigee Edge documentation.
Go to the Apigee X documentation. info

Introduction

This topic explains how to use the apigee-access to access the Apigee Edge quota service from a Node.js application. With apigee-access, you can apply and reset quota values.

Example

var apigee = require('apigee-access');
var quota = apigee.getQuota();
quota.apply({ identifier: 'Foo', allow: 10, timeUnit: 'hour' },
    function(err, result) {
         console.log('Quota applied: %j', result);
    });

Methods

• apply
• reset

apply

Modifies the settings on a Quota object. Use this method to increment or decrement the quota, change time intervals, and make other configurations.

Usage

var apigee = require('apigee-access');
var quota = apigee.getQuota();
quota.apply({parameters}, callback);

Example

var apigee = require('apigee-access');
var quota = apigee.getQuota();

        // Apply a quota of 100 requests per hour
        quota.apply({
         identifier: 'Foo',
         timeUnit: 'hour',
         allow: 100
        }, quotaResult);
                
                function quotaResult(err, r) {
                 if (err) { console.error('Quota failed'); }
                }       

Parameters

The apply() method takes two parameters, an object and a function:

(1) The first parameter is a JSON object with these fields:

• identifier (string, required): A unique identifier of the quota bucket. In practice it might be an application ID, IP address, or username.
• timeUnit (string, required): How long the quota bucket will accumulate until it is reset. Valid values are "minute," "hour," "day," "week," and "month."
• allow (number, required): The maximum value for the quota bucket. This value will be combined with the current value to return whether the quota has succeeded.
• interval (number, optional): Combined with the "timeUnit" to determine how long before the quota is reset. The default is 1. Set to a larger value to allow quotas such as "two hours," "three weeks," and so on.
• weight (number, optional): The value to increment the quota by. Default is 1.

(2) The second argument is a callback function with these two arguments:

• The first argument is an Error object if the quota cannot be incremented, or undefined if the operation succeeded.
• The second is an object that contains the following fields:
  • used (number): The current value of the quota bucket.
  • allowed (number): The maximum value of the quota bucket before the quota is considered to be exceeded. The same value was passed as "allow" in the request object.
  • isAllowed (boolean): If there is room left in the quota -- true as long as "used" is less than or equal to "allowed."
  • expiryTime (long): The timestamp, in milliseconds since 1970 format, when the quota bucket will be reset.
  • timestamp (long): The timestamp at which the quota was updated.

Example

var apigee = require('apigee-access');
var quota = apigee.getQuota();
 

// Apply a quota of 100 requests per hour
quota.apply({
  identifier: 'Foo',
  timeUnit: 'hour',
  allow: 100
}, quotaResult);
 

// Apply a quota of 500 requests per five minutes
quota.apply({
  identifier: 'Bar',
  timeUnit: 'minute',
  interval: 5,
  allow: 500
}, quotaResult);


// Increment the quota by a value of 10
quota.apply({
  identifier: 'Foo',
  timeUnit: 'hour',
  allow: 100,
  weight: 10
}, quotaResult);


function quotaResult(err, r) {
  if (err) { console.error('Quota failed'); }
}

reset

• A JSON object with these fields:
  • identifier (string, required): A unique identifier of the quota bucket. In practice it might be an application ID, IP address, or username.
  • timeUnit (string, required): How long the quota bucket will accumulate until if it is reset. Valid values are "minute," "hour," "day," "week," and "month."
  • interval (number, optional): Combined with the "timeUnit" to determine how long before the quota is reset. The default is 1. Set to a larger value to allow reset times such as "two hours," "three weeks," and so on.
• A callback function:
  • The callback takes an Error object as the first parameter if the reset fails.

Advanced Quota use case

• syncInterval (number, optional): The number of seconds that the distributed quota implementation syncs its state across the network. The default is 10.