Amazon Trade-In Command-Line Tool

Make queries to Amazon Trade-In from the command line. Amazon has a great app for scanning books for trade-in, but for checking eligibility periodically, it becomes rather tedious.

The Solution

The books that are eligible for Amazon Trade In vary over time. And what's more, how much certain items are worth also seem to vary over time.

With that in mind, I wanted to be able to save a list of items I'm trying to get rid of, and then periodically check in without having to scan a bunch of books, DVDs and so forth every time.

Usage

First, you'll need credentials. The trade-in value data is retrieved through the Product Advertising API, and the documentation details the credentials you need to access it. They are:

- API Access ID
- API Secret Key
- Associate ID

With those in hand, you can:

sudo pip install aws-trade-in

This installs the command-line utility aws-trade-in, which can be invoked:

aws-trade-in --access-id ... --secret-key ... --associates-id ... --dir books

The above command will recurse through the books/ directory, looking for files, where each is expected to contain a list of bar code numbers (SKUs) of books, dvds, etc. with one SKU per line:

9780760724064
9780786881857
9780806961743
9780896086289
9780743284257
9780452263499
...

Getting Bar Codes

We made use of the Bar-Code app for iPhone since it can email the lists of bar codes you scan. This made it easy to go through our books and dvds once, and not have to type anything in ourselves.

Results

It then provides a summary of which items are eligible, and if so, how much Amazon will give you. For example, with the number of books we have around the house that we're trying to slowly get rid of, we organize our books:

books/
    bookshelf-1/
        shelf-0
        shelf-1
        shelf-2
        shelf-3
    hallway-bookshelf/
        ...

When the results are printed out, they're organized by the file they're from, so that given the summary you can quickly find your books:

Reading 16 skus in /..../books/bookself-1/shelf-0
    9780760724064: Not Eligible : Twentieth-Century Small Arms: ...
    9780786881857: Not Eligible : Don't Sweat the Small Stuff--a...
    9780806961743: Not Eligible : The Little Giant Book of Optic...
    9780896086289: Not Eligible : Feminism Is for Everybody: Pas...
    ...
Reading 15 skus in /..../books/bookshelf-1/shelf-1
    ....