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USPS Webtools API for Ruby
Latest commit 77020c0 @adelevie adelevie Merge pull request #15 from adelevie/add_link_to_18F_guide
Added further reading section to readme


Build Status

Ruby API for accessing the USPS WebTools API found here:

PDF Guides can be found here:

Usage of this library assumes you already have a USPS API account and that all priviledges have been granted.

Project Status - Looking for a Maintainer

This code is no longer properly maintained as I'm no longer with the company it was developed for. If you're using it and would be interested in maintaining it please send me a message and I can get you set up.

Exposed API Calls

The following USPS API calls are currently exposed through this library:

<AddressValidateRequest>             -- USPS::Request::AddressStandardization
<CityStateLookupRequest>             -- USPS::Request::CityAndStateLookup
<ZipCodeLookupRequest>               -- USPS::Request::ZipCodeLookup
<TrackRequest>                       -- USPS::Request::TrackingLookup
<TrackFieldRequest>                  -- USPS::Request::TrackingFieldLookup

<DeliveryConfirmationV3.0Request>    -- USPS::Request::DeliveryConfirmation        (for production)
<DeliveryConfirmCertifyV3.0Request>  -- USPS::Request::DeliveryConfirmationCertify (for testing)


Using the library is as simple as building a new USPS::Request::[type] object, calling #send! and using the response. For example, to send a tracking request you'd do the following:

request =
response = request.send!


The library assumes that either ENV['USPS_USER'] is set, or that you set USPS.username to your USPS API username.

See the individual USPS::Request classes for details on how to use them.

USPS API Certification

Part of the process of setting up an account with the USPS API is to run certain tests against the USPS API. This library has all the requisite tests built in, runnable with rake:

$ USPS_USER="[username]" rake certify

or as an installed gem:

$ USPS_USER="[username]" ruby -rubygems -e "require 'usps/test'"

If any of the tests fail, you don't have access to that API and may need to work with USPS to fix it.

Note on Patches/Pull Requests

  • Fork the project.
  • Make your feature addition or bug fix.
  • Add tests for it. This is important so I don't break it in a future version unintentionally.
  • Commit, do not mess with rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
  • Send me a pull request. Bonus points for topic branches.


$ rspec

Further Reading


Copyright (c) 2014 Chris Gaffney. See LICENSE for details.

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