Amazon.com : Java Glossary

Introduction

Amazon.com keeps a database of all its products including books, electronics and DVDs (Digital Video Discs). an enormous online bookstore that carries many Java related books. It includes pictures and prices, but not detailed descriptions. Each country has its own separate database. They sometimes use the same ASIN number for the same product. You can use this data to embed links to Amazon stores on your own webpage. When people buy products you get a small commission.

Types Of Links To the Amazon Websites

On the mindprod.com website, I use a variety of affiliate links to the Amazon.com website:

types of links to Amazon.com

Types of Links To Amazon.com
text link to a specific book	Java Concurrency in Practice
image link to a specific book
CMP (Canadian Mind Products) Book Macros	Book referral for Programming Amazon Web Services: S3, EC2, SQS, FPS and SimpleDB recommend book⇒Programming Amazon Web Services: S3, EC2, SQS, FPS and SimpleDB by James Murty 978-0-596-51581-2 paperback publisher O’Reilly  978-0-596-55179-7 eBook published 2008-04-01 B004OR1JF0 kindle It covers: S3 : online storage to store and retrieve data EC2 : online computing to be able to run jobs on a farm of machines SQS : web messaging infrastructure for computer-computer communication FPS : flexible payment system for moving money online SimpleDB : store and retrieve datasets online It is about doing your computing by renting Amazon servers. It is not about using the AWS Amazon Product Advertising API to do book referrals. Online bookstores carrying Programming Amazon Web Services: S3, EC2, SQS, FPS and SimpleDB abe books anz abe books.ca abe books.de amazon.ca amazon.de Chapters Indigo amazon.es Chapters Indigo eBooks iberlibro.com abe books.com abe books.fr amazon.com amazon.fr Barnes & Noble abe books.it Nook at Barnes & Noble amazon.it Kobo junglee.com Google play abe books.co.uk O’Reilly Safari amazon.co.uk Powells other stores Greyed out stores probably do not have the item in stock. Try looking for it with a bookfinder. Book referral for Java Concurrency in Practice recommend book⇒Java Concurrency in Practice by Brian Goetz, Tim Peierls, Joshua J. Bloch, Joseph Bowbeer, David Holmes, Doug Lea 978-0-321-34960-6 paperback publisher Addison-Wesley 978-0-13-270225-6 eBook published 2006-05-19 B004V9OA84 kindle Bloch and Lea especially have very good reputations in concurrent programming. This is the dream team to write such a book. Online bookstores carrying Java Concurrency in Practice abe books anz abe books.ca abe books.de amazon.ca amazon.de Chapters Indigo amazon.es Chapters Indigo eBooks iberlibro.com abe books.com abe books.fr amazon.com amazon.fr Barnes & Noble abe books.it Nook at Barnes & Noble amazon.it Kobo junglee.com Google play abe books.co.uk O’Reilly Safari amazon.co.uk Powells other stores Greyed out stores probably do not have the item in stock. Try looking for it with a bookfinder.

AWS (Amazon Web Services) Programmer API (Application Programming Interface)

Screen scraping will drive you insane at Amazon because the pages are formatted inconsistently, they make ever increasing use of JavaScript and they change the layouts frequently just to keep things interesting.

Thankfully, they have created a programmer’s API. called AWS or more recently the PA-API (Product Advertising Application Programming Interface). Actually there are dozens of dozens of them actually, to let you do all manner of things including getting the information about a book in computer-friendly and reasonably stable form — XML (extensible Markup Language) / SOAP (Simple Object Access Protocol). Each country has its own servers, own accounts, own passwords, own XML schema… Unfortunately for batch processes, they don’t want you to do more than 200 inquiries per hour. Oddly, the problem is too much documentation and too many samples. You are overwhelmed. Don’t try to make sense of the complicated stuff until you gave found introductory docs and mastered the basics. Read the Getting Started Guide materials first. To help avoid overloading Amazon’s servers, find a response format that includes just what you need. Amazon issues you user IDs and passwords to use on all queries so they can track what you are up to with the API. They also insist that all queries be digitally signed and sent with HTTPS (Hypertext Transfer Protocol over SSL (Secure Socket Layer)). You can sign by computing your own RFC 2104-compliant HMAC-SHA256 digital signature, or you can use Oasis WSS (Web Services Security) SOAP -Style signing, using your own X.509 certificate or one provided by Amazon. I guess they are preparing for a sophisticated DOS (Denial of Service attack) attack.

To use it you will need:

• An Amazon account for buying books.
• An Amazon affiliate account for selling books.
• An AWSaccount for using the API.
• You need to WSimport the default http://ecs.amazonaws.com/AWSECommerceService/AWSECommerceService.wsdl 2011-08-01 or perhaps the latest at http://ecs.amazonaws.com/AWSECommerceService/2013-08-01/AWSECommerceService.wsdl 2013-08-01. See (WSDL location) so that JAX understands the grammar of the responses, not just with an XSD (XML Scheme Definition), but with generated Java code. The document defines the XML responses and the URLs (Uniform Resource Locators) of the Amazon stores that accept AWS probes.

• Convert the *.wsdl to Java source code with:

You don’t need AWS SDK (Software Development Kit). All you need is AWSECommerceService.wsdl, and Java’s built-in JAX features.

There is a utility called the Amazon Product Advertising API Signed Requests Helper that helps you understand how queries are constructed. It sorts the parameters alphabetically, adds a timestamp and digitally signs the request to form a GET URL (Uniform Resource Locator). It is a little out of date. The URLs it uses do not match those in the JAX spec. Here is what a typical query looks like:

Fields to use in your inquiries you may find of interest include:

• AWSAccessKeyId=XXXXXXXXXXXXXXXXXXXXXX
• AssociateTag=canadianmindprod
• IdType=ASIN
• IdType=EAN
• IdType=ISBN
• ItemId=9780618918249
• Keywords=harry+potter
• Operation=ItemLookup
• Operation=ItemSearch
• ResponseGroup=AlternateVersions
• ResponseGroup=Images,ItemAttributes
• ResponseGroup=Images
• ResponseGroup=ItemAttributes (List Price)
• ResponseGroup=ItemIds
• ResponseGroup=Large
• ResponseGroup=Medium
• ResponseGroup=OfferFull
• ResponseGroup=OfferListings
• ResponseGroup=Offers
• ResponseGroup=OfferSummary (lowest new and used price)
• ResponseGroup=RelatedItems&RelationshipType=AuthorityTitle
• ResponseGroup=Small
• ResponseGroup=Variations
• SearchIndex=All
• SearchIndex=Books
• SearchIndex=DVD
• SearchIndex=Electronics
• SearchIndex=Music
• Service=AWSECommerceService
• Timestamp=2012-02-17T02%3A46%3A44.000Z
• Version=2010-11-01
• Signature=XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Fields of interest in the responses include:

• amount
• author
• availability
• binding
• ean
• isbn
• largeImage
• lowestSalePrice
• mediumImage
• publicationDate
• publisher
• smallImage
• title

You do not directly specify which fields you can in response, but you can specify constellations of names called ResponseGroups.

The XML response has a complex tree structure, it is not just a matter of requesting the field you want.

You can batch up to ten queries in on request.

They also have SDK s for half a dozen languages. I don’t know much about it.

Other Countries

• You can use the same AWSAccessKeyId/secret key pair for both the amazon.com and amazon.ca. It most probably works on all other countries as well.
• You need a separate associate id for each country.
• Happily there is a common AWSECommerceService.wsdl schema for all the stores. You just use a different port. This means you can use the same generated JAX files.
• Each country has its own AWS server, or endpoint as Amazon so foppishly calls them.

You don’t use SNI (Server Name Indication). You must have Symantec Class 3 Secure Server CA - G4 root cert installed in your JVM (Java Virtual Machine).

The web is littered with obsolete lists of the endpoint URLs. You can find the most recent list inside AWSECommerceService.wsdl. You don’t use the endpoints directly unless you are experimenting with Amazon Product Advertising API Signed Requests Helper. Otherwise you use the corresponding port getter e.g. AWSECommerceService.getAWSECommerceServicePortCA() or AWSECommerceServicegetAWSECommerceServicePort() ; and JAX looks effectively looks up the corresponding end point in AWSECommerceService.wsdl (using pre-generated code). Note that Amazon in Spain (Amazon.es) and Amazon in India (Junglee.com) originally did not support AWS, but now it does do. Unlike the other Amazon stores, Junglee will not let you register as an affiliate unless you are resident of India. I suspect they will not let you probe their AWS database either. Amazon in Australia (Amazon.com.au), Amazon in Brazil (Amazon.com.br) and Amazon in Mexico (Amazon.com.mx) still do not. Amazon in Australia and Amazon in Mexico have no paper books or electronics, just kindles and kindle eBooks. I don’t include them on my site book referrals.

TestItemSearch: Sample Code For Amazon AWS API

It took weeks to get this little sample program to use the Amazon AWS API working. Even the Signed Requests Helper utility took days to get working. The problem is Amazon makes their API more and more complicated each year, but do not update the documentation and they refuse to provide complete example code. I have never in my career of 55 years seen a more incompetently documented API. Further, the API is not consistent. Further, it is often idiotic, e.g. returning the number of results as a BigInteger when even a short would have done fine.

It uses SSL (Secure Sockets Layer) but not SNI. You must have the root certificate for Symantec Class 3 Secure Server CA - G4 installed in your cacerts.

AwsHandlerResolver

I downloaded this AwsHandlerResolver code from the Amazon website, then modified it to use the more compact CMP Base64 classes. AwsHandlerResolver handles the poorly documented stuff like adding a timestamp, digitally signing your request and Base64 ASCII-armouring the signature.

FetchBookFacts

The following is a more complicated example. You give it an ISBN-13 (aka EAN (European Article Number) ) on the command line and it probes the Amazon API to find the title, author, publisher, published date. It also probes for the ISBN-13s of alternate bindings, e.g. Paperback, Hardcover, Kindle, Audio. It creates a text file (in the form of an HTML (Hypertext Markup Language) macro) summarising this information and downloads the large bookcover image. It does not include the author birth/death dates since Amazon does not track them. On my website, those fields are added later by code part of HTMLMacros.

IsASINInStock

The following takes either an isbn13 or ASIN and probes the Amazon.com AWS API to find out if the product is in stock. The results do not correspond well with the information on the website. I don’t know which is actually correct.

Amazon in India

Amazon in India is puzzling. Instead of being called Amazon.in they called it Junglee.com. You could not probe its inventory with AWS using getAWSECommerceServicePortIN even though that port was defined in the to AWSECommerceService.wsdl file. You had to screen scrape the consumer interface. You could not sign up as an affiliate unless you lived in India. I get perhaps a third of my traffic from India, but I was still excluded. To my surprise, Junglee had the largest inventory of any Amazon store.

Then on 2014-08-23 a new, separate website appeared called Amazon.in alongside Junglee.com without any explanation of its relationship to Junglee.com.

I tried to contact Amazon.in via their website for clarification. They refused to talk to me unless I provided them with a fake cell number. They asked me a number of impertinent questions, then to cap it off gave me no space to pose my questions. I am soured on them already.

Tips

• There does not appear to be a way to specify a timeout on your AWSECommerceService probes. I am having trouble with everything freezing on long runs.
• Amazon does not take PayPal.
• Use the Signed Requests Helper utility before you try to write an Java code. It lets you rapidly experiment with various requests, it shows you the complete result and it is easier to pick out embedded error messages.
• The API is quite slow, about 6 seconds to get the information for one book. This is slower than screen scraping the website intended for humans. However, I found if I submitted a request more frequently than once every 20 seconds to amazon.com or every 10 seconds to the other Amazon sites they would start refusing to respond to my probes. You are supposed to be able to probe once a second, even faster if you are a major customer.
• Google the entry web, not just amazon.com for code snippets using the same of methods and parms. Amazon’s website is nearly always out of date, incomplete and just plain wrong. You need to find examples elsewhere and do a lot of experimenting.
• You don’t need the Amazon SDK. I don’t know what it is for, perhaps languages other than Java.

• Convert the *.wsdl to Java source code with:

• After you generate the Java source from the AWSECommerceService.wsdl, just insert it into your project as if you had hand-written it. You can monitor if they have changed the API with Vercheck. The current default version is 2011-08-01. The latest version is 2013-08-01 Last revised/verified: 2014-07-22.
• Try modifying the sample code I have given you, then morphing it gradually to what you need.