The second line also contains the version of Product Advertising API used to create the response. In this
example, the version number is 2011-08-01. If a version is not specified in a request, Product Advertising
API uses the default version, 2005-10-05. Make sure to specify the latest version number if you want the
latest Product Advertising API functionality.
Operation Request Segment
The second segment of a response is always the Operation Request. For the most part, it returns the
operation's parameters, called arguments, that were used in the request. There is, however, some
additional information. The first large subsection is the HTTPHeader section, which specifies the network
agent used to send the request. Typically, the agent, called the user agent, is a web browser and the
information returned describes that browser, such as its name, version, and the operating system of its
host.
The second large subsection contains the arguments, or operation parameters, used in the request.
These values are unprocessed echoes of the values submitted in the request. This information is echoed
for the benefit of troubleshooting requests.
Finally, interspersed around the large subsections in the Operation Request segment is Product Advertising
API processing information, including the Request ID and the time it took to process the request. This is
interesting information for troubleshooting. You will not, however, have to use either the Request ID or
the processing time in future requests.
Request Validation Segment
The segments described so far are typically less interesting than the ones that follow. The Request
Validation segment contains error information if there was an error in the request. It is also the last segment
that Product Advertising API returns in a response if there was an error.
In the preceding example, the request was valid, as shown in the IsValid element.
<IsValid>True</IsValid>
The IsValid element pertains only to the validity of the request. It reports whether all of the required
elements of a request are present, whether parameter restrictions and constraints have been obeyed,
and whether parameter values are legal. IsValid does not assure that a valid request will be processed
by Product Advertising API. For example, an ItemId, such as, 1234ABCD, is in the correct form, but no
items in Amazon's catalog match that ItemId, so, the request would be valid but would return an error.
There are many reasons why a request can fail, as described in the following table.
API Version 2011-08-01
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Responses
