Print stamps with Ruby!
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Stamps is backed library for creating postage labels, calculate the shipping cost of packages, standardize domestic addresses via USPS CASS certified Address Matching Software, and track shipments.

Main Features

  1. Create postage stamp labels in png and pdf formats.

  2. Standardizes shipping address that complies with the USPS address formatting guidelines.

  3. Validates city, state, and postal code combinations.

  4. Calculate shipping rates based on distance and package weight.

  5. Request USPS carrier pick ups.

  6. Track shipment history.

  7. Purchase postage.


Register for the Developer Program to receive a free test account.

Sample Workflow

  1. Standardize Shipping Address - Ship-to addresses must be standardized based on USPS rules for proper address conventions before a shipping label can be issued.

  2. Get Rates - allow users to view and select the best shipping service for their needs.

  3. Generate the Shipping Label - after choosing a shipping service and ship-to address is standardized, the Stamps.create method will generate the indicium required to ship the item. If the customer changes their mind, they may want to select an option that initiates a Stamps.cancel. Stamps.cancel refunds postage and voids the shipping label.

  4. Print the Shipping Label - Call the returned URL to obtain the shipping label image. A URL is returned by the Stamps.create call in the :url item. The integration will connect to this URL to retrieve their shipping label and customs forms for printing.

Getting Started

Once you have a test account with integration id, we can simple pass them to the configure block:

# Authenticate you credentials
Stamps.configure do |config|
  config.username       = 'STAMPS USERNAME'
  config.password       = 'STAMPS PASSWORD'

Now we can now be able to retrieve information about our account:


Standardized Shipping Address

Standardizes shipping address that complies with the USPS address formatting guidelines

standardized_address = Stamps.clean_address(
  :address => {
    :full_name => 'The White House',
    :address1  => '1600 Pennsylvania Avenue, NW',
    :city      => 'Washington',
    :state     => 'DC',
    :zip_code  => '20500'

Get Rates

To get a list of rates for all available USPS services based on the ZIP Code or the foreign country being shipped to for a given package weight and size.

rates = Stamps.get_rates(
  :from_zip_code => '45440',
  :to_zip_code   => '20500',
  :weight_lb     => '0.5',
  :ship_date     => '2011-04-07'

Creating a shipping label

To generate the postage based on the shipping information provided in the request. The create! method will return a URL that references either an image of the domestic shipping label or a multi-page PDF document for international labels with customs forms.

stamp = Stamps.create!(
    :tracking_number => true,
    :rate          => rates.first,
    :to            => standardized_address,
    :from => {
      :full_name   => 'Littlelines',
      :address1    => '50 Chestnut Street',
      :address2    => 'Suite 234',
      :city        => 'Beavervcreek',
      :state       => 'OH',
      :zip_code    => '45440'
    :memo => 'Thanks for shopping with us!'

Now we can view or print the postage label:


General Configuration

If you want to see the data logged to and from the api:

Stamps.configure do |config|
  config.log_messages = true

By default Stamps will return responses as a Hash. To make Stamps return a Hashie instead:

Stamps.configure do |config|
  config.format = :hashie

A return address can be specified in the configuration block as well. This address will be used when the :from address is not specified when creating new stamps

Stamps.configure do |config|
  config.return_address = {
    :full_name    => 'Littlelines',
    :address1     => '50 Chestnut Street',
    :address2     => 'Suite 234',
    :city         => 'Beavercreek',
    :state        => 'OH',
    :zip_code     => '45440',
    :phone_number => '9375545027'

Installation Steps

First install the gem:

gem install stamps

Add it to your Gemfile:

gem 'stamps'


Pull requests are very welcome! Make sure your patches are well tested. Please create a topic branch for every separate change you make.


Matt Sears