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Hack 82 Climbing Out of the Sandbox

Dealing with certification and going
"live."

eBay is
understandably protective about any access it permits through its
API. To that end, they provide the Sandbox, a
"dummy" eBay site with which you
can test your programs to your heart's content.

The Sandbox is located at cgi.sandbox.ebay.com/, and looks (and acts)
just like eBay.com. Although it's nearly fully
functional (some features don't work at all), its
auction and user databases are completely separate from the main eBay
site.

The idea is that you can create user accounts, list items, bid, and
even check out, all without incurring the fees and API call limits
that would otherwise prevent you from freely testing your application
or scripts.

Although the Sandbox is not bug-free and is often a few months behind
eBay.com when it comes to new features and interface changes,
it's stable where it counts. It's
accepted as fact that any code that works in the Sandbox will work on
the live eBay.com site.

8.2.1 Certification

Before your application goes
"live," meaning that it can be used
on what eBay calls the "production
servers" (not just the Sandbox), you must complete
certification.

Now, the fact that certification is a required step and costs money
($100 for Individual-tier developers) may make it seem more like a
barrier than a service. However, eBay's reasoning is
that it ultimately benefits developers as much as it benefits eBay.

For developers working under the Individual license, the certification fee is the only tangible cost of entry to going live.

First and foremost, certification involves testing your script or
application to ensure that it operates efficiently and causes minimal
impact on the performance of eBay.com. Certification also permits
developers to display the eBay Certified Developer Logo in their
applications; while this may not mean so much to individual
developers (it is not even available under the Individual license),
it is absolutely vital for those creating commercial applications to
gain the confidence of their customers.

Here's how certification works:

Review the certification requirements (see the next section).

Submit the API Usage Document (available at enough information to understand how your product will be accessing
the eBay API and eBay content.

Submit a Certification Request.

eBay works with you to test your application, which essentially
involves hooking it up to a special debug server and analyzing the
traffic it generates.

Provided that you've met the certification
requirements, eBay estimates that your program should be certified
within a week.

Recertification is necessary only if your application substantially
changes the way it uses the API.

8.2.2 Certification Requirements

The following requirements must be met by your
application in order
for it to pass certification:

Error Handling. Make sure you look for and handle any errors received from API calls.
For instance, if you're using a single API call
repeatedly, make sure the loop halts if an error is encountered. All
of the scripts in this chapter incorporate some degree of error
checking.

Efficiency. One of the primary reasons for certification is to ensure that your
application or script handles communication with eBay responsibly and
efficiently. See [Hack #99] for
details.

Compatibility Levels. The eBay API is constantly changing and evolving to keep up with
eBay.com. It's important to keep track of these
changes, especially if you're using some of the more
obscure fields or API calls listed in the documentation. The
Compatibility Level ($compat_level) specified in
config.pl ensures that these changes
won't affect your program, at least until eBay
removes support for your compatibility level (which they do
periodically).

For instance, the Seller.User.Sunglasses field was
replaced with the Seller.User.NewUser and
Seller.User.UserIdChanged fields as of API version
305, to correspond with changes to the main eBay site. If your
program were to submit an API call with compatibility level 309, you
wouldn't have access to the
Seller.User.Sunglasses field.

All the scripts in this book reflect compatibility level 309. If you encounter a script or function that doesn't work for you, refer to the API documentation for possible changes associated with later compatibility levels.

Specific call requirements. In addition to the previous rather general requirements,
certification also requires certain procedures to be followed with
regard to many of the individual API calls. Here are a few
examples:

Every time your application retrieves comments from a feedback
profile, it should cache or record the data so that it retrieves only
newly added feedback records each time. See [Hack #96] for details.

You should use GetItem (described in [Hack #84]) only if the information you need
cannot be retrieved through more efficient means such as
GetSellerList (described in [Hack #87]).

Use the GetSellerList call only to retrieve
listing data for the first time; use
GetSellerEvents to subsequently retrieve price
changes, bids, item revisions, or other changes that might have
occurred since the auction data was last retrieved.

License requirements. Finally, your application must fall within the limits of your license
agreement. For instance, if you're working under the
free Individual license, you can't redistribute your
applications (nor would you want to, given the number of API calls
that would be required by hundreds of users).

As the API gains popularity, it remains to be seen how strict the
certification requirements will remain, and how rigorously eBay will
enforce recertification for large changes to your code.